r • ..,
INTERNATIONAL COUNCIL FOR THE EXPLORATION OF THE SEA CONSEIL INTERNATIONAL POUR L' EXPLORATION DE LA MER
::"...... C.M. 1992/Assess :8
PARTl
..... '. "'. .":.
"'WORKING GROUP ON Nephrops AND Pandalus STOCKS
ABERDEEN, 26 FEBRUARY - 5 MARCH 1992
This document is areport of a Working Group of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council. Therefore,
it should not be quoted without consultation with:
the General Secretary ICES Paloogade 2-4 DK-1261 Copenhagen K Denmark CONTENTS
PART 1
1 TERMS OF REFERENCE AND INTRODUCTORY NOTES...... 1
2 PARTICIPANTS...... 1
3 THE PANDALUS STOCKS WITHIN ICES SUB AREA IV AND DIVISION JI[ ...••••••.•• •• 2 3.1 Pandalus Stocks in Sub-area IV and Division J1[a 2 3.2 Natural Mortality ...... 2 3.3 Skagerrak and the Norwegian Deeps 2 3.3.1 Landings...... 2 3.3.2 Discards 2 3.3.3 Effort...... 2 3.3.4 Assessment...... 2 3.3.4.1 Age distributions ...... •..... , 2 3.3.4.2 ~fean weight at age , 2 3.3.4.3 Natural mortality ...... •. 3 3.3.4.4 VPA ...... 3 3.3.4.5 Recruitment 3 3.3.4.6 Catch prediction ...... 3 3.4 Fladen Ground ...... 3 3.4.1 The Fishery 3 3.4.2 Effort data 3 3.4.3 Assessment...... 3 3.4.3.1 Age distribution of the catch ...... 3 3.4.3.2 Mean weights at age ...... 4 3.4.3.3 Natural mortality " 4 3.4.3.4 VPA ...... 4 3.4.4 Management considerations ...... 4 3.5 Farn Deeps ...... •. .. 4
4 UTILIZING ANNUAL LENGTH COMPOSITIONS IN THE ASSESSMENTS OF NEPHROPS ....4 4.1 Length Cohort Analysis . 4 4.2 Summary of alternative approaches examined by the "Methods" Working Group . 4 4.3 Description of method employed during the Working Group . 5 4.3.1 Introduction . 5 4.3.2 The Slicing program . 5 4.3.3 Virtual Population Analysis and tuning . 5 4.3.4 Predictions . 6 • 4.4 Icelandic approach . 7 4.4.1 Introduction . 7 4.4.2 Annual growth data ...... •. 8 4.4.3 Age based assessment . 8 4.4.4 Catch predictions and discussion ...... 8 4.4.5 Comparison of Icelandic approach with Working Group approach using the SE Ice- land stock as an example ...... •...•...... 9 4.5 Future approaches and developments ...... •.... 9
5 NEPHROPS STOCK ASSESSMENTS AND CATCH POSSIBILITIES ...... •...•• 9 5.1 General introductory notes 9 5.1.1 Functional Units and Management Areas ...... 9 5.1.2 Fishery data and the problem of unreported landings 9 5.1.3 Assessments and inputs 10 5.1.4 Management considerations; provision of catch options...... 10 5.1.5 Section layout ...... 11 •
5.2 Management Area Va (Area A) ...... •...... 11 5.2.1 Ieeland ...... •...... 11 5.2.2 Summary of Management Area Va (Area A) 12 5.3 Management Area Vb (non EC) (Area B) ...... •..•...... 12 5.3.1 Faroes (Functional Unit 2) 12 5.3.2 Summary of Management Area Vb (non EC) (Area B) ....•...... 12 5.4 Management Area VIa (Area C) .•.....•...... •...... •..••.•...... 12 5.4.1 North Minch (Functiona1 Unit 11) ...... •...... 12 5.4.2 South Minch (Functional Unit 12) ...... • 13 5.4.3 Firth of Clyde (Functional Unit 13) ...... ••.. .. 14 5.4.4 Summary for Management Area VIa (Area C) ...... •...... •.... 15 5.5 Management Area Vb (EC) and VIb (Area D) 16 5.5.1 Summary for Management Area Vb (EC) and VIb ...... 16 5.6 Management Area IlIa (Area E) ...... 16 5.6.1 Skagerrak (Functiona1 Unit 3) ...... •...... 16 5.6.2 Kattegat (Functional Unit 4) ...... •...... 16 5.6.3 Summary for Management Area IlIa (Area E) ...... •...... 17 5.7 Management Area IVa 44-48 E6-E7 + 44E8 (Area F) ...... •..• 18 5.7.1 MorayFirth(FunctionaIUnit9) 18 5.7.2 Noup (Functional unit 10) 19 5.7.3 Summary for Management Area IVa 44-48 E6-E7 + 44E8 (Area F) 19 5.8 Management Area IVa Remainder (Area G) 19 5.8.1 Fladen Ground (Functiona1 Unit 7) ...... ••.....• 19 5.8.2 Summary for Management Area VIa remainder (Area G) 20 5.9 Management Area IVb,c East of 10 East (Area H) ...... 20 5.9.1 Botney Gut - Silver Pit •...... •..•...... •.. 20 5.9.2 Summary for Management Area IVb,c East of 10 East (Area H) ...... 23 5.10 Management Area IVb,c West of 10 East (Area I) ...... •...... •. .. 23 5.10.1 Farn Deeps (Functional Unit 6) •..•.....•...... •...... 23 5.10.2 Firth of Forth (Functiona1 Unit 8) ...... 25 5.10.3 Summary for Management Area IVb,c West of 10 East (Area I) .....•...•.. .. 26 5.11 Management Area VIIa (excluding 33E2-33E5) (Area J) 26 5.11.1 Irish Sea East (Functiona1 Unit 14) ...... ••...... 26 5.11.2 Irish Sea West (Functional Unit 15) ...... 27 5.11.3 Summary of Management Area VIIa (excluding 33E2-E5) (Area J) ..••...... •. 29 5.12 Management Area VIId,e (Area K) ...... ••...... 29 5.12.1 Summary of Management Area VIId,e (Area K) ...... •..•...... 30 5.13 Management Area VIIb,c,j,k (Area L) 30 5.13.1 Porcupine Bank ...... •...... • 30 5.13.2 Aran Grounds (Galway Bay) (Functional Unit 17) 31 5.13.3 Republic ofIreland Coast (NW, Wand SW) (Functiona1 Units 18 and 19) .•...•.. 32 5.13.4 Summary of Management Area VIIb,c,j,k (Area L) ...... 32 • 5.14 Management Area VIIf,g,h and VIIa: rectangles 33E2-E5 (Area M) ...... ••..... 32 5.14.1 Celtic Sea (Functional units 20+21 +22) 32 5.14.2 Summary for Management Area VIIf,g,h and VIIa 33E2·E5 (Area M) 34 5.15 Management Area VIlIa,b (Area N) 34 5.15.1 Bay of Biscay (Functional Units 23 +24) ...... 34 5.15.2 Summary of Management Area VIlIa,b (Area N) 36 5.16 Management Area VIlIc (Area 0) ...... 36 5.16.1 North Galicia (Functional Unit 25) 36 5.16.2 Cantabrian Sea (Functional Unit 31) ...... •...... 37 5.16.3 Summary of Management Area VIlIc (Area 0) ...... 37 5.17 Management Area VIlId,e (Area P) 37 5.17.1 Summary of Management Area VIlId,e (Area P) ...... 38 5.18 Management Area IXa (Area Q) ••...•....••....•...... ••...... •. 38 5.18.1 West Galicia (Functional Unit 26) ..••...... •.. 38 5.18.2 North Portugal (North of Cape Espiche1) - Functional Unit 27 38 5.18.3 South West and South Portugal (Functional Units 28 and 29) ...... •... 40 5.18.4 Gulf of Cadiz (Functional Unit 30) ...... • 42 5.18.5 Summary for Management Area IXa (Area Q) .....•.....•...... •..•• 42 5.19 Management Area IXb and X (Area R) ...... 42 5.19.1 Summary of Management Area IXb and X (Area R) 42
6 TRAWL EFFICIENCY AND FISHING POWER IN NEPHROPS FISHERIES ...... 43 6.1 Introduction...... 43 6.2 Northem Ireland fleet 43 6.3 Swedish fleet .....•...... 43 6.4 Fleet and fishing gear developments in Scotland 43 6.4.1 Fleet survey 43 6.4.2 LPUE in relation to vessel and gear characteristics 44 6.4.3 Comparison between single- and multi-rig Nephrops trawls 44 6.5 Conclusions...... 44
7 TRANSFER OF WORK TO AREA BASED WORKING GROUPS 44
8 NEXT VENUE 45
9 REFERENCES...... 45
TABLES 47
PART 2 FIGURES...... 191
• 1 TERl\ISOFREFERENCEANDINTRODUC- In recent Nephrops Working Group reports an Annex has TORY NOTES been included containing summary information on Nephrops in each Functional Unit. This was drav.TI up at The Working Group on Nephrops Stocks met in the commencement of the systematic assessment of Aberdeen, Seotland from 26 February to 5 March 1992 Nephrops using the length basoo LCA approach. Since to: there has recently been a move towards the use of more 'age based' methods some of the information in the a) Review and improve technieal aspects of the Annex cannot be readily updated while at the same time existing assessments and evaluate the possibil additional information is now available. It was decided ities of utilising annual length composition on this oceasion to omit the Annex. An updated rede information in the assessments; signed Annex will be included periodically in the future onee the assessment methodology has become more b) Update the information where necessary (ie firmly established. where input parameters have signifieantly ehanged) for Nephrops stocks in the ICES area on the state of exploitation and catch possibil 2 PARTICIPANTS ities; The following scientists attendoo the meeting of the e) Assess the status of stocks of Pandalus borealis Working Group: in the North Sea, Skagerrak, and Kattegat; Ms M. Aschan Norway d) quantify if possible,increases in trawl efficieney N. Bailey, Chairman UK, Scotland and fishing power in fisheries for Nephrops and D. Bennett UK, England • diseuss the implieations ofsueh inereases for the D. Bova UK, Scotland assessment of eurrent fishing mortality; . R. Briggs UK, Northem Ire1and Ms F. Cardador Portugal e) prepare for the transfer ofits work to area based C. Chapman UK, Seotland working groups, advise how this might be best R. Cook, UK Scotland aehieved, consider what difficulties might arise H. Eiriksson Iceland and how these could be overcome. C. Farina Spain P. Billis Ireland The Working Group has addressed each ofthe above five J. Kinnear UK, Scotland terms of reference, the results and discussions are Ms C. Mosquera Spain contained in the Chapters 3-7. Chapter 3 covers the S. Munch-Petersen Denmark assessments of Palldalus (item c) and is essentially a self F. Redant Belgium eontained chapter. Ms C. Talidee Franee S. Tveite Norway Chapters 4 to 6 deal with Nepllrops issues. Chapter 4 M. Ulmestrand Sweden examines further the use ofannuallength distributions in the assessment of Nepllrops (item a) and, in addition to In addition, the following information was received non outlining the principle method used at the Working partieipants: • Group together with a similar approach, presents some suggestions for making short term predictions. Chapter D. Boddeke, Netherlands: "I am sorry to inform you that 5 provides the details of the assessments on Nephrops I will not attend the Nephrops/Palldalus Working Group including the presentation of catch options. Chapter 6 meeting. There will be no data to supply because the gives some preliminary information on developments in Duteh fleet does not fish on these species. During the fishing gear and efficiency whieh have implieations in the last 5 years no landings of Pandalus borealis have been measurement of effort. It should be noted that there is recorded in the Netherlands.• some cross referencing between these three chapters. R. Meixner, Germany: "In 1991 as in 1990 again there Chapter 7 allempts to provide some constructive guid were praetically no Nephrops and Palldalus landings by anee on the incorporation of Palldalus and Nephrops German boats: 1991, approx. 2 tonnes Nephrops and 1 assessments into the areal groups formed following the tonne Palldalus.• 1991 ACFM consultations on the subject.
Following the text section of the report the Figures and Tables may be found for all chapters and page numbers appropriate to each species are given in the contents. 3 TUE Pr\NDr\LUS STOCKS WITIIIN ICES give a very rough estimate of 350 tonnes discarded small SUB AREA IV AND DIVISION 111 shrimps,which is approximately 18 % of the Swedish landings in 1991. The Norwegian way of sorting the 3.1 Pandalus Stocks in Sub-area IV and Dh'ision catch is similar to that of the Swedish, while the Danish lila statistics give the total catch. The discard estimates represent a considerable amount and when more data are A detailed overview of the various stocks is given in available and these are incorporated in the catch at age Anon. (l990b). The Working Group assurnes three data some changes in the size of age-group 1 are to be managements units (Figure 3.1.1) expected. Therefore, the Working Group recommends that estimates of discards for the earlier years are 1. Skagerrak amI Norwegian Deeps combined provided for the next Working Group meeting. 2. Fladen Ground 3. Farn Deeps 3.3.3 Effort
Nominal landings for Division I1Ia and Sub-area IV are Quarterly and annual figures for catch and effort are shown in Table 3.1.1. given in Table 3.3.2. The Danish and Norwegian total effort values have been estimated from CPUE data based 3.2 Natural l\Iortality on log-book records covering approximately 95 % of the Danish and 40 % of the Norwegian total catches for For some years The Palldalus Working Group has been 1991.Danish and Swedish data are available for the aware that the values for M (natural mortality) used in whole period, whereas Norway provided data for 1986 the assessments of the Palldalus stocks may not be very onwards. realistic. On the initiative of ACFM and the ICES MSVPA Working Group, tentative estimates of total Norway reduced its effort by 11 % from 1990 while • consumption of Panualid Species in the North Sea was Sweden and Denmark increased effort by 5% and 30% presented to the ICES Statutory Meeting in 1991 (Daan, respectively. 1991) using the ICES MSVPA Working Group database. 3.3.4 Assessmcnt In order to use these results as a basis for estimating predation mortalities some further analysis of the results 3.3.4.1 Age distributions will be requireu. This will hopefully be completed before next year's assessment of the PaJldalus stocks. I1owever, National quarterly sampIes of length frequencies from it is pertinent to note here, that the estimated consump Division I1Ia and the Norwegian Deeps were split into tion of Pandalid species in the North Sea according to normal distributions. Each normal distribution (assumed Daan (1991) indicate that the predation mortality compo to represent an age group), is described by mean length, nent of natural mortality may exceed the magnitude of standard deviation, and proportion of total sampie size. the presently estimated fishing mortalities several foId. If The time series of mean lengths of the age groups are this is confirmed in the further analysis of the data, the shown in the Figure 3.3.1. A maximum of six age Working Group has to reconsider the assessment methods groups was identified. (VPA and Standard Prediction) hitherto applied to these Palldalus stocks. The quarterly national catches (in tonnes) were converted to catch in numbers at age by applying the number of In the assessments presented here, however, the values shrimps per kg in the sampies together with the age • of M used in previous years are maintained. distributions. Quarterly national figures of catch in numbers at age were aggregated to provide the yearly 3.3 Skagcrrak und the Nonn~gian Dccps data (Table 3.3.3.).
3.3.1 Landings 3.3.4.2 l\Iean wcight at age
Table 3.3.1 gives, by country, the Working Group The Norwegian weights at age were obtained by applying estimates of lamlings since 1970 from the Skagerrak and quarterly length/weight relationships based on Swedish Norwegian Deeps combined. The totallandings increased data from 1990, while the Danish and Swedish mean to nearly 12000 tonnes in 1991 due mainly to increased weights were obtained by applying average weights of catches in the Skagerrak area. shrimps for each mm group on the length frequencies of each year-class, estimated by splitting the total length 3.3.2 Discard~ composition. Table 3.3.4. gives weights at age in the catches. The mean weights at age in the stock were Sweden provided data on discarus for 1991. These data assumed to be equal to mean weights in the catch.
2 The maturity ogi,':e for shri~p varies from year to year. higher than the VPA estimate for i990. It is estimated as the proportion of intersexes and females in the 2-group in the first quarter of the year, amI is as In Table 3.3.9 we have also included estimates of 1990 fo11ows: and 1991 year-classes as I-group based on log-log regression between O-group survey indices and VPA 1985 1986 1987 1988 1989 1990 1991 figures (Figure 3.3.3). The 1991 estimate (7116 miIIions) is used as input in the catch prediction. 0.62 0.09 0.20 0.30 0.68 0.73 0.73 3.3.4.6 Catch prediction The 0- and l-groups are assumed to be immature, and the 3-group and older groups fu11y mature. Input data for the prediction are shown in Table 3.3.10. The fishing pattern used is the 1986-1990 average scaled 3.3.4.3 Natural mortality to the 1991 level. Mean weights are averages for the period 1986-91, and recruitment in 1993 and 1994 is the As in previous years M has been set to 0.75 for a11 ages. average for the period 1986-1990. The data on predation on shrimps mentioned in Section 3.2. are expected to provide hetter estimates of natural The status quo catches are predicted to be 13 000 t in mortality for the next Working Group meeting. 1992 and 11000 t in 1993 (Table 3.3.11). This is a reduction from last years prediction.The high 1989 0 3.3.4.4 VPA group index is now included in the regression for estimates of the recruiting I-group. If omitted, the 1991 The level of fishing mortality in 1991 was estimated by )'ear-class estimate as I-group is, however, only tuning with national effort data. Input for the tuning is increased by 10 %. • given in the Table 3.3.5. For a11 three fleets the terminal catchability (q) was estimated as the mean since no trend 3.4 Fladen Ground was obvious. F for the oldest non-plus age group (age 4) was set to the mean of age groups 2 and 3. The results 3.4.1 The Fishery are shown in Table 3.3.6. Table 3.4.1 shows the landings from the Fladen Ground The resulting values of mean F on both ranges 1-3 and since 1972. Totallandings in 1991 declined to 475 tonnes 2-3 (Table 3.3.7) show only an insignificant decrease in (less than 1/4 of the 1990 landings). Approximately 80 1991. % of the fishery took place in the 2nd quarter. The reason for the drastic decline in the fishery during The estimated stock sizes indicate increasing total and 1990-91 has been the declining prices for shrimp and the spa\\ The 1991 O-group index is below the average of the 7 3.4.3 Assessment previous indices. 3.4.3.1 A~e distribution or the catch The 1990 year class was estimated as 2-group from regression ofVPA 2-group on l-group survey indices. A The age distribution ofthe catch was estimated from data log-log regression was used and gave an estimate of4142 on length composition ofthe catch using the Bhattacharya millions at age 2. (Figure 3.3.4., Table 3.3.9.) This is method as before (Anon.1991c). Length sampIes were 38% higher than the 1986-1990 VPA average and 8% available for the 2nd quarter only, but since most of the 3 fishery took place in that quarter, the age composition of Group decided to base the VPA on the standard tuning the landings in the 2nd quarter has been raised to the module. annual landings. Tables 3.4.9 and 3.4.10 show the estimated F-values and Tbe results of the splitting ofthe length distributions into corresponding stock sizes. As a consequence ofthe lower age components are shown in Table 3.4.4. The figures F-values the estimated stock biomasses have increased in for the 4th quarter were derived from the Danish trawl the years 1988-90, but the pattern of variation is the survey and cannot be used to split up the landings. same as in previous years' assessments. Figure 3.4.1 shows the estimated mean lengths of the estimated age groups, which seem to be reasonably 3.4.4 l\Ianagement considerations consistent from year to year. Table 3.4.5 gives the resultant catch in numbers by age group. Both the CPUE figures for 1991 (Tables 3.4.2 and 3.4.3) and the relative stock sizes for 1989-91 estimated from 3.4.3.2 l\Ienn wei~hts at a~e VPA (Table 3.4.10) indicate quite large stock sizes but a rather low level ofexploitation in 1991. Tbe reason for Mean weights at age in the 1991 landings (Table 3.4.6) the reduced exploitation was the dramatic drop in market were calculated on the basis of figures for mean weights price for Pandalid shrimps. Tbis has for the time being by length group in the length sampIes, i.e. using the rendered the fishery for Fladen shrimps unprofitable. estimated normally distributed length groups constituting each (estimated) age group. The mean weights in the Tbe Norwegian and Danish survey data on O-group stock were assumed to be the same as in the catch. shrimps still cover too few years to be used for recruit ment predictions. Tbe maturity ogive used is shown below. It is based on the observed number of berried females from the first 3.5 Farn Dccps • quarter in 1989 and 1990 (Danish and Scottish sampIes). Tbe proportion mature at age 2 was about 60 %: In 1991 Pandalus in the Farn Deeps were fished by English vessels only. Totallandings fell from 145 tonnes Age o 2 3 4+ in 1990 to 3 tonnes (see Table 3.5.1). Tbis decline in the fishery is believed to be a consequence of the above Prop. mature 0.0 0.0 0.6 1.0 1.0 mentioned general lowering of market price for Pandalid shrimp. 3.4.3.3 Natural mortality As in previous years, 1\1 has been set to 1.0 (Anon., 4 UTILIZING Al\'NUAL LENGTII COl\lPOSI 1977) for the Fladen shrimps. However, revised values TIONS IN TUE ASSESS:\IENTS OF NEPII· for natural mortality (including more realistic values for ROPS predation mortality) are expected to be available for the next Working Group meeting (cf. Section 3.2). 4.1 Len~th Cohort Analysis 3.4.3.4 VPA No new developments to the length cohort analysis technique or software were made. In spite of the decline in the Fladen fishery and the correspondingly few catch at age data, a VPA is pres 4.2 Summary ofalternative approachcs examined • ented. However, because of the low values for fishing by the "l\Iethods" Working Group mortality the results must be viewed cautiously. The Working Group on Methods of Fish Stock Assess Terminal F-values were estimated by the standard tuning ment was asked to consider alternative length-based module, designed for disaggregated effort data and methods to the LCA, as applied to Nephrops stocks normally used by ICES Working Groups. Table 3.4.7 (Anon. 1991b). Five analytical methods were tried using gives input data (note that the combined ScottishlDanish male Nephrops data from three stocks: SE Iceland and index is used) and Table 3.4.8 gives output results. The the Firths of Forth and Clyde. Two cohort slicing estimated F-at-ages for the )'ears 1988-90 became methods used growth information to convert annual somewhat lower compared to those from last years' length distributions into 'age' compositions. Tbe resulting VPA. This is to be expected because of the extremely catch-at-a,ge data were then analysed by conventional low effort values given as input for 1991 in the tuning VPA, employing Laurec-Shepherd or ad hoc tuning. Tbe procedure, which is not particularly well suited to cope other methods were adaptations on CASA (Sullivan et with such scanty data. Howcver, in order to maintain al., 1990), age-based time series analysis (Gudmundsson, continuity of previous years' assessments the Working 1987) and ADAPT (Mohn and Savard, 1989). CASA and 4 one cohort slicing method were also tried at last year's likely true age so that all 'nominal ag~s' quoted are Nephrops Working Group in preliminary analyses ofdata lower than in reality. from the Clyde stock (Anon., 199Ia). The length compositions for slicing were those used in The 'Methods' Working Group Report concluded that the last years length cohort analysis, updated or comple two cohort slicing programs and Mohn's formulation mented with any newly available data. Inputs to the produced similar estimates and trends of biomass, mean program were the numbers of removals, ie the landings F and recruitment on all stocks and fitted the tuning data plus the dead discards. For most functional units the similarly. This consistency was encouraging for their discard survival was taken to be 0.25 (Table 5.1.3). The future use in Nephrops assessments. These three methods growth parameters of the von Bertalanffy equation were use the familiar age-based models al ready widely those used last year (Table 5.1.3), as were the length employed in ICES assessment working groups. This weight relationships. Most ofthe slicing done on females could make them ideally suited to the assessment of used two growth curves for the immatures and matures, Nephrops in future area-based working groups provided with a transition length equal to the size at 50% matur they can be shown to produce reliable results. CASA and ity. Gudmundsson's method are essentially length-based and likely to be unfamiliar and less readily adaptable to the The slicing program allows a choice for the number of area-based working groups. age groups to which the lengths are allocated. Trial runs were made and the number of age groups restricted to a The ADAPT method of Mohn and Savard showed reasonable number which at the same time showed a particular promise but is wriUen in APL language and reasonably smooth tailing off without leaving a very was not available to this Working Group. It is hoped to large plus group investigate this more fully in the near future (see below). • The most readily available software was the slicing and The program provides output ofthe numbers at 'nominal VPA package produced by R. Cook of the SOAFD, age' by year, together with the mean weights at age. Aberdeen. Abrief description of this method is given in Tables of these data are given for each Functional Unit Section 4.3. assessed (for example Table 5.10.17 anti 5.10.18 for the Firth of Forth males). Using the length/weight relation 4.3 Dcscription of mcthod cmplo.lcd during the ship these mean weights coulJ easily be converted Working Group manually to mean lengths for comparison with the more familiar Nephrops length distributions; a useful develop 4.3.1 Introduction ment might be an option in the program to provitIe these automatically. The program also provides an output file The method introduced by Robin Cook at the 1991 in a format suitable for use in the VPA. Nephrops Working Group involves a two stage process of 'slicing' followed by a tuned VPA along the lines used 4.3.3 Virtual Population Analysis and tuning in finfish assessment. The slicing applies growth, in the form of the von Bertalanffy model, to the numbers at The VPA program uses directly, files produced by the length to slice them into 'nominal age' groups. There slicing program anti while in theory any time span can be were some modifications to this methods following last used, it was consitIered unwise to proceed with a VPA if year's Working Group and these are detailed below. the data series was shorter than five years. The fishing Since this method was used in the routine assessments, mortality tuning approach incorporated in the program is • detailed results have been presented in the section on that of Laurec/Shepherd which uses effort data. The Nephrops assessments (Section 5). To avoid duplication program can accommodate one or more fleets and allows there is, in the presentation which folIows, some cross selection of those to be utilised in the tuning. The referencing to Section 5. program provides numerous options for the tuning procedure which are discussed below; those chosen for 4.3.2 The Slicing program each Functional Unit are summarised in Table 5.1.4. This program makes no attempt to separate overlapping Marginal Fs were chosen with reference to expectations age groups, but simply allocates Iength groups to ages. derived from the Length Cohort Analysis. Where Fs in Where the knife-edged slicing limit falls within a length the VPA were reasonably high the analysis proved to be group the numbers at length are allocated on a propor relatively insensitive to the input Fs. For females, where tional basis. The program was adapted to allow the the LCAs gave quite low Fs for many functional units, incorporation of two length at age curves to cover the input Fs were chosen erring on the high side, rather than different growth pallerns ofimmature and mature female on the low one. Nephrops. It should be noted that no attempt has been made to adjust the youngest age in the slicing (1) to a F on the oldest age group was not fixet! but taken as the 5 average of preceding 'age' groups (usually 3). Choices terms of total stock biomass, recruitment and numbers at were available for handling trends in catchability (q) the first age, ami trends within these. Tbe sex ratio at through time in the series of data for each fleet. The recruitment would be expected to be about equal, but in choices were for a linear trend line to be fitted, or a most functional units female stock biomass is often weighted average. Tbe weighting could be chosen, and greater than for males as F on males is generally higher where the data series was fairly short, say less than Sill due to their greater availability. It is again worth pointing years, the weighting was zero. Where there was thought out that the results of female assessments need to be to have been a change in q due to, for example a mesh treated with caution beeause in general they were typified change, then a tri-cubie weighting was used with maxi by very low F values and by tuning results which mum weight assigned to a specified year prior to the indicated high variance abaut F. Male results with higher most recenl. In addition historie F could be inc1uded as F values were generally more reliable and it is suggested an additional series and in some cases this made a that more attention is paid to these. valuable contribution to the tuning. An option to take natural logs of values was available and this was usually In most cases it was feIt unwise to read too much at this taken. stage into the estimated biomass and recruitment trends. For those showing most promise, however, the examin Tbe tuning output enabled an assessment of the most ation of trends may in the future prove fruitful. Figure appropriate choices by reference to the weighting given 4.3.1 shows, for Firth ofForth males, changes over time to average q or historie F, and the relative variance of of a number of indicators of stock condition. Higher the F estimates. Tbe final choices adopted varied yields in the mid 1980s were associated with generally between functional units (Table 5.1.4). In the multifleet high F values. Recently, F has continued high but assessments effort data was often only available for one lamlings have fallen and the stock biomass appears to be fleet, so the others were exc1uded from the tuning. in decline. On the other hand recruitment has been steady (the low value in 1991 is due to unreliability in the most • Not all tuning results are presented here. Table 4.3.1 recent year of the VPA). shows an example of male tuning output from a stock, the Firth of Forth, for which the VPA performed rather Other means of verifying the VPA results could also be weil. Note that the variance about Fis mostly very small investigated in the future, these inc1ude examination of compared with the tuned F value. Compared with this, the relationship between TSB estimates from the VPAs the female results for the same stock (Table 4.3.2) are (sexes combined) and the LPUE observed in the fishery. not so good with re1atively large variances particularly on An example from the Firth of Forth (Figure 4.3.2) the younger ages. Table 4.3.3 gives an example (for the shows that there is quite elose agreement between the Moray Firth males) where historie F has been inc1uded. two variables. Note that the wcighting given to historie F is comparable to that for the fleet data. Tables 4.3.4 and 4.3.5 come 4.3.4 Prcdictions from the assessments of Functional Units 28 and 29, the SW and S Portuguese stock. For these the VPA did not At the 1991 Working Group, a method ofprediction was perform so weIl (see below). Notice that the variances presented and adopted in the presentation of catch about F for the males of this stock are substantially options. Tbis made use of the relationship between bigger than in the Firth of Forth males. It is intended for landings and fishing efforl. Where the relationship was the future to adopt the Lowestoft tuning package which good and there was no evidence of a time trend then provides a standardised output ami allows the plotting of predictions could be made; for example if there was a catchability coefficients and should allow c10ser examin • requirement for status quo effort then the average for the ation of results. LCA reference period was computed and used to predict landings from the relationship. Tbis method has again For summary purposes, Mean Fs were generally chosen been used this year. over an age range whieh exc1uded the younger ages (these being only partially recruited), and the poorly By way ofexample, the Firth of Forth results are shown sampled older ones. To test the "quality" of the VPA and in Figure 5.10.7 and Table 5.1.5. (this table also the tuning the mean Fs were plotted against effort ami summarises results for all other areas). Tbe need for correlations made. Tbe results were quite variable effort to be at least stabilised was reiterated as for last between functional units, with some giving highly year and taking the average effort in the reference period correlated outputs such as that for the Firth of Forth (in fact almost identical to the 1991 level) implied (Figure 5.10.6) while others such as the Portuguese stock landings of 1791 tonnes. Since, however, the 1991 point mentioneu above (Figure 5.18.6) suggesteu that F was was weil below the fitted line, there was concern that independent of changes in effort or that there was a this landing option might in fact allow for increased negative correlation. Tbe results were further evaluated effort. Accordingly an option with a 20 % reduction in by making comparisons between males and females in effort was inc1uded which gave a landing option of 1405 6 tonnes overall. and catch in 1993 and 1994. With the adoption of 'age' based assessments at this Since the assessments were carried out on removals (ie Working Group lending themselves to an annual landings plus dead discards) the predictions were adjusted approach, other prediction methods are possible. The to allow for this (assuming that future discard practise is first of these makes use of fishing mortality from VPA the same as in 1991).The landings figures quoted are instead of effort in a predictive plot with landings, therefore true landings (not removals including discards). similar to that above. Since assessments of males and The text table below summarises the results: females were carried out separate1y, two plots of land ings against FBAR are required, these are shown in 1992 Status quo Figure 4.3.3 together with the computed least squares re1ationships; both relationships are significant. A TSB Landings prediction can be made using F in the most recent year, Males 3770 1100 rather than some average of an earlier period. Using the status quo and 20 % reduction approach discussed above Females 4759 425 the results in the following text table are obtained: Total 8529 1525 Status qua 20% Reduction 1993 Status quo 20% Reduction FBAR Landings FBAR Landings TSB Landings TSB Landings Male 0.986 1234.3 0.789 1098.1 Males 3857 1143 3857 976 Female 0.207 695.9 0.166 572.4 Females 4823 454 4823 369 Total 1930.2 1670.5 Total 8680 1597 8680 1345 1994 Status quo F as in 1993 TSB Landings TSB Landings This method yiel<.led slightly higher options than the first one <.Iescribed possibly because the correlation for males Males 3896 1163 4152 1104 (Figure 4.3.3) was not very good and the 1991 point was Females 4851 470 4962 396 weIl below the line. In fact, 1989 and 1990 points were also below the line. In these circumstances the use of this Total 8747 1633 9114 1500 type of relationship might not be advisable since even though arecent series of landings are lower than expected, the prediction allows for higher landings which probably implies higher than desirable effort. The results suggest that under status quo conditions of fishing mortality, that the total stock biomass will Another type of prediction is the more traditional increase marginally while landings in the prediction years approach regularly employed as part of the age based will be between 1525 and 1633 tonnes. These figures are assessment of finfish species and demonstrated for noticeably lower than in the other two prediction methods Pandalus borealis in Section 3. Here an average pattern and might weIl be more reasonable for the Firth of Forth • of fishing mortality is scaled to the most recent year and stock. With a reduction in fishing mortality rate the stock used to roll forward estimates of the stock number to biomass shows a faster increase while landings at first provide predictions of stock biomass ami catch for a drop and then begin to recover in 1994. An obvious limited time into the future. advantage in this method is the ability to predict the stock biomass and there is c1early scope to develop this Tables 4.3.6 and 4.3.7 show respectively for males and further before the next Working Group. females, inputs for one such short term prediction for the Firth of Forth stock. Note that there is no recruitment 4.4 Icelandic approach index so an average is taken of the 1981·90 recruits at 'age 1'. Also, since the 2 year old numbers at the start 4.4.1 Introduction of 1992 are not re1iably estimate<.l, the average of '2 year aids' has been taken over the same period and used to Age-based methods have been used for several years in overwrite the stock size at the start of prediction year the analysis of the Icelandic Nephrops stocks (Eiriksson, 1992. Fishing pattern is the average over 1981-90 and 1979; 1982; Anon., 1989; 1991a). Assessments carried out the F values are scaled to the 1991 level. Successive on this stock in the 1991 Report incIuded a comparison applications of the exponential tIecay equation antI the hetween LCA and VPA age-based methods. While catch equation are used to give estimates of stock size comparable estimates of mean F were obtained by the 7 two methods there were differences in the stock biomass The VPA was tuned to the age-wise regressions ofeffort estimates. The method involves length cohort slicing to and F (or Z, where M=0.2) as weIl as to weighted generate age-groups (Table 4.4.1) using growth informa average F(5-13) (Figure 4.4.5). A seeond VPA run was tion mainly derived from the deteetion of year-c1ass carried out with higher input F on ages 6-7 beeause of modes in the length composition of catches, supple possible targeting of fishing effort on areas of high mentOO by tagging. The slicing procOOure provides catch abundance of these year-c1asses. at-age data for analysis by VPA. Details of the Icelandic approach were presentOO in the form ofa working paper Fishing mortalities at age are shown in Table 4.4.4 and (Eiriksson,1992) which is summarisOO in Sections trends in mean F(6-13) and landings are given in Figure 4.4.2-4.4.4. Seetion 4.4.5 includes, for part ofFU 1 (the 4.4.6. The numbers at age generated by the VPA SE coast) a comparison of results derived from the together with fishable stock biomass (CL 35+mm, age Icelandic approach and that adopted by the present \V/G. 6 +) are given in Table 4.4.5. The trends in biomass and reeruitment over the 1970·1992 period are shown in 4.4.2 Annual J;fowth data Figures 4.4.7 and 4.4.8, including the effects of the two input F options mentionOO above. Aperiod of good Tagging experiments have resulted in 113 reeaptures reeruitment occurrOO in 1975-78 (mainly 1971-72 year (0.7% of releases) of which 72 were 1 or 2 years at c1asses) which resulted in increasing biomass (Figure liberty. However, only 12 individuals had definitely 4.4.7) and LPUE (Figure 5.2.3) up to 1980-82. Although moulted with growth increments ranging from 2 to 6 mm LPUE was very high in 1985-86 (Figure 5.2.3), the in periods of 9 to 24 months (Table 4.4.2). stock biomass appears to have fallen relative to 1980-82 (Figure 4.4.7). This 100 to an underestimate of Fs at the In the analysis of length frequency distributions of time and to over predictions of stock biomass (see catches a procedure referred to as the 'percentage points below). The high LPUE in 1985-86 was later ascribed to deviation method' was used to highlight the presence of above average catchability. By 1988-89 the stock biomass • year-classes (Skuladottir, 1981). In this, comparisons are had fallen to only 11-12 thousand tonnes, comparOO to 16 made between the annuallength composition and the long thousand tonnes in 1980-82 (Figure 4.4.7), due to very term average for several years (Figures 4.4.1 and 4.4.2). low reeruitment in the early 1980s (Figure 4.4.8). Strong The annual growth of year-c1asses identifiOO by this year-c1asses from 1984-85, however, have resulted in an method are then analysed by Ford-\Valford plots to increased biomass since 1989, which may possibly reach estimate von Bertalanffy growth parameters (Figure about 14-15 thousand tonnes by 1992. This prOOiction 4.4.3). These parameters are usOO to slice the length may be rather optimistic since it implies larger year composition into age groups, a similar method to that c1asses in 1984-85 than previously recordOO. outlined in Seetion 4.4.3. In the Icelandic case real ages are estimated by ascribing age 2 to the 13-18 mm CL 4.4.4 Catch predictions and discussion cohort (Table 4.4.1). Figure 4.4.3 suggests that growth differences between S\V and SE Iceland are minimal and Table 4.4.6 provides the projections of fishable stock therefore combined age compositions can be used to biomass according to different management options for assess the whole Nephrops stock in FU 1. 1992 and 1993 catches. The rate of exploitation of Icelandic Nephrops has aimOO for F(O.I), which equates 4.4.3 AJ;c hased assessment to F=0.22 according to the present pattern of exploita tion (Figure 4.4.9). This complies reasonably weIl with VPA assessments are performed on males only since they a TAC reeommendation of 2000 tonnes for 1992 set by constitute almost all the landings during the main fishing the Icelandic Marine Research Institute. Exploitation at • season, mid-May to mid-August. AIIlamlings are raisOO the rate of Fmax would be expectOO to lead rapidly to a to catches assuming no survival of discards. Table 4.4.3 very uneconomical fishery due to declining LPUE, shows the total catch expressed as numbers-at-age for the smaller mean sire of animals and lower catch value. years 1971-1991. The age distribution of the 1991 catch Moreover recruitment may be put at risk, particularly shows a somewhat larger proportion of ages 7-8 than since the females have a biennial spa....ning regime and predicted by the 1990 assessment (Figure 4.4.4). This reach maturity at a relatively large sire. may be due to a growth difference between these two years. Figure 4.4.4 shows the continued predominance of Figure 4.4.10 shows various biomass prOOictions pro ages 6-7 (1984-85 year-c1asses) as described in last years vided for the Icelandic stock during the last 10 years in Report (Anon.,1991a). These year-classes have resulted comparison to the 20-year VPA. Apart from the period in an increasing biomass amI LPUE from 1990 (see around 1986 when Fs were underestimated due to Figure 5.2.3) as predicted in the 1989 Report unusually high catchability, the predictions have fallen (Anon.,1989). within reasonahJe limits. 8 ; 4.4.5 Comparison or Icclandic approach ",Hh boundaries. The main difficulty in keeping to this aim \Vorking Group approach u<;ing the SE Ice was in IVa, lVb,e, and VIIa/VIIg. The Management land stock as an example Areas are described, together with the Functional Units they contain, in Table 5.1.2, and are shov.n by lCES Using the slicing amI VPA described in Section 4.3 on a Sub-area, Division and/or Working Group boundaries in subset of the Icelandic data ie. the SE of Iceland male Figure 5.1.1 to 5.1.3 stock, the catch at age and weight at age data shov.n in Tables 4.4.7 and 4.4.8 were obtained. Tuned VPA The Working Group notes that eurrent TACs are set for results are shov.n in Tables 4.4.9 and 4.4.10 for F at age rather large areaS based on lCES Sub-areas or divisions. and numbers at age respectively. Summary outputs of The Working Group wishes to reiterate its view that yield, FBAR, stock biomass ami recruitment are shown Nephrops are more appropriately managed at a smaIler in Table 4.4.11. The VPA performed rather weIl and the scale, it is aware that management at the individual unit plot ofFBAR against effort gave a significant correlation level is probably impractical but again recommends that (Figure 4.4.11). The comparable results using the the Management Areas described are adopted. Specific Icelandic methods ofsplitting and VPA were very similar examples of potential problems inherent in the current and so are not reported fuIly here. An illustration of the system are: similarity between the methods may be seen in Figures 4.4.12 and 4.4.13 which show the time trends of FBAR i) Sub-Area IV North Sea: The rapidly developing and stock biomass respectively for the two methods. Fladen Ground fishery could cause problems for other fisheries within the North Sea under the 4.5 Future approaches and dcnlopments existing single TAC arrangement. It is conceiv able that the TAC could be laken early from this The Group was optimistic that there was scope to ground prior to the full potential being realised • develop further an age-based assessment approach. For on other grounds. several units there was good correlation between mean F and effor!. With time to consider fuIly the inputs and the ii) Sub-Area VII: In this area the TAC covers a approach taken, the Group recognized the benefits which large area and offers no restrictive effect for could accrue from the ability to make annual estimates of some of the fisheries contained within it. In F, stock biomass, and recruitment. A number of refine Sections 5.11.1 and 5.11.2 it is pointed out that ments to the software utilised were considered, but there the recommendations for FUs 14 and 15 were was insufficient time to implement them at this meeting. overshot in 1991 while for Area VII as a whole there was an undershoot of the TAC. In particular it was felt that i) the Lowestoft version of the tuning programme should be employed to further 5.1.2 Fishery data and the problem or unreported iIluminate the results of the tuning procedure; ii) The landings Mohn-Savard method should be fuIly investigated; iii) the short term prediction method should be considered for as Where possible, Working Group members again pro many stocks as reliability of the VPA assessment vided landings statistics by lCES statistical rectangle allowed. which were used to raise sampIes to fleet level prior to assessments. In view of the need for reliable statistics These and other developments could be considered by a particularly because of the shift towards annual catch at • meeting of the Nephrops Study Group (see Section 7). age analysis and the requirement to provide catch options as a basis for the setting of TACs, care was laken to ensure that due account had been taken of all potential 5 NEPIlROPS STOCK ASSESSl\IENTS AND landings. CATCII POSSIBILITIES As part of this process attention was paid to the 1992 5.1 General introductory notes TACs set on the basis of last years advice from ACFM. The Working Group noted that in the case of the North 5.1.1 Functional Units and l\Ianagcment Arcas Sea TAC (12000 t) this was set rather higher than the sum ofthe recommendations for the constituent Manage The Functional Units are defined by the groupings of ment Areas. The Working Group understands that at rectangles given in Table 5.1.1 and ilIustrated in Figure least 500 tonnes of this was to aIlow for unallocated/un 5.1.1 to 5.1.3. There were no changes to the descriptions reported landings. given last year (Anon, 1991a) An attempt was made to account for these unallocated The Management Areas have been described using, as landings. There is no evidence of any directed fishing [ar as possible, existing leES Sub-area amI Division which the Working Group has overlooked. The \Vorking 9 ;; Group is aware of the fleets involved and takes into FU LCA VI)A consiueration all the potential Nephrops grounus. The Working Group also considereu potential bycatch of * 2 +90 other fleets although temporal restrictions prevented a detailed examination of these. On the basis of the 3&4 * information available, however, the Working Group S * * found it difficult to account for such large quantities of 6 * unallocated catches and suggests that the extent of them 7 * in the North Sea has been highly exaggerated. 8 * 9 * For the present assessments, no allowance has been made 10 for unallocated landings, numbers at age are raised to the 11 * * weights reporteu to the Working Group. For the future 12 * this problem needs to be addressed more thoroughly to 13 * * ensure that assessments anu predictions truly reilect the 14 + catches made. 1S * 16 5.1.3 Asscssmcnts and inputs * 17 * 18 The term of reference indicated that if there were no changes to the inputs then 1991 assessments did not need 19 to be repeateu. Examination of the length compositions 20-22 * resulting from the aduition of one more year's worth of 23&24 * data mostly showed that there was no difference and the 2S * • LCA was not repeated. 26 + 27 * Making use of the method described in Section 4, 'age 28&29 * based' assessments were carried out for each Functional 30 Unit where sufficient uata were available. The text table 31 + sho....n opposite lists the new assessments carried out (indicated *). For some FUs there are insufficient data to carry out any assessment (indicated -) and for some there was no additional assessment after last year (+). Section 4 offer some promise, because of reservations As in 1991, assessments were conducted on males and about the quality of some assessments and the lack of females separately, these frequently gave rather different recruitment indices the Working Group feit that their results. The reasons for adopting this approach have been adoption was at this stage prernature. Similarly, for a discussed before (Anon. 1991a) and are based on the number of stocks it was feit that the new VPA results greater availability and probably vulnerability of males. were uncertain or uifficult to interpret so considerable emphasis was placed on the LCA results obtained last Biological input parameter values for the assessments are year. Where the addition of a length class made no summarised in Table 5.1.3, the same parameters are difference to the average it was taken to indicate that the required for LBA and for the 'Iength splitting/VPA' LCA would have given identical results. • approach. There were no changes from the values given last year. For providing catch options the same rationale as last year was adopted for each stock making use where Tuning inputs are summarised in Table 5.1.4. possible of the relationship between landings and effort. It has been argued that updating the series of landings 5.1.4 l\lanagcmcnt considcration,,; prOl'ision or and effort with one additional year and reca1culating the cateh options predicted landings is not necessary. It was, however, felt that if the addition ofnew data made no difference to the Where the results showeu a clear difference in exploita length distribution then a new prediction should be given tion pattern between males and females the Working as ifan assessment had been conducted. Accordingly the Group again felt that management options should be most recent data year, 1991, was added to the series and directed towards the most vulnerable component, most a new relationship calculated. the summaries ofthese are frequently the males. given in Table 5.1.5. Baseu on the assessment results of last year with any new insights from the age based Although the alternative types of prediction described in approach of this year, a catch option was calculated and 10 presented. In practise these frequently varied very little stable, averaging around 2500 tonnes per year. How from those given last year. ever,from 1987 to 1990, landings fell from around 2700 tonnes to 1700 tonnes due to lower recruitment from 5.1.5 Scction la.}'Ilut small year classes of the early 1980·s. However, 1991 saw an increase in landings up to almost 2200 tonnes The remainder of the stock assessment section (Section whieh can be Iinked with stronger year classes estimated 5) is organised according to Management Area and then from 1984-85. A small creel fishery of 10-30 tonnes a by Functional Units contained within each area. year was initiated in 1989 (Table 5.2.2) its future remains uncertain. For each Functional Unit, information on landings, effort, LPUE and mean size precedes a description of the length based assessment where appropriate or notes explaining the reasons for not repeating it. This is LPUE fell rapidly from around 80 kglhr at the beginning followed by sections on the age based approach (where of the fishery in the early 1960's to only some 30-40 appropriate) for males and females. Catch possibilities kglhour by the late 1960·s. For most of the 1970's the are then given. LPUE remained at around 35-40 kglhour (Figure 5.2.3). In 1981-1987 the LPUE ranged from 46-61 kglhour Summaries of the catch possibilities for the Management peaking in 1985-1986. This peak is, however, thought to Area are then given. be connected with unusual catchability rather than stock abundance. Catch options are summarised in Table 5.1.6 From 1987 to 1989, the LPUE dropped from 53 to 36 5.2 Management Area Va (Area A) kglhour (Table 5.2.1) but has increased again to 42 kglhour in 1991. The improvement is thought to be Functional Units - Iceland (I) related to increased recruitment from the 1984 and 1985. This event was predicted in 1988 when there was a high 5.2.1 Iceland proportion of 20-30 mm CL Nephrops in the catches (Anon, 1989) Landin!.!s/Catches Mean Size Landings of Nephrops at Iceland were first reported by Belgian trawlers in the early 1950·s. However by around The mean size of both sexes fell rapidly at the initiation 1970, foreign lamlings were mostly limited to a small of the Nephrops fishery in the early 1960's (Figure number of French stern trawlers. Owing to extension of 5.2.4). Small mean sizes were evident in the 1970's the fishery limit to 50 and later 200 miIes, the fishing of owing to high fishing intensity in previous years and to Nephrops by foreign vessels was discontinued in the good recruitment from 1970-1973. Subsequently these early 1970s. Figure 5.2.1 shows long term trends in same year classes led to marked increases in mean size landings. in the laie 1970's reaching a peak in 1987. From 1989 to 1990 there has been a drastic drop in mean size owing to The Icelandic Nephrops trawling fishery started in the the strong recruitment ofthe 1984-85 year c1asses (Table late 1950's and fishing effort and landings grew rapidly 5.2.3) • the latter reaching a peak of 5500 tonnes in 1963 (Fig ures 5.2.1 and 5.2.2). Another peak in landings of 4700 Although fishing mortality on females is considered to be tonnes was realised in 1971. Following these peaks, much lower than on males, the mean size of both sexes however, landings fell ralher drastically by 50% or more show similar trends. That may reflect the high discard within only 2-4 years. The fishery with its falling catch mortality of soft post-moult females that are ubiquitous rates (Figure 5.2.3) reached a point of great economic in the summer fishing season as weil as the concurrent instability by the mid 1970's . effects of recruitment and growth on both sexes. Since 1974 the fishery has been managed by annual Assessments TACs with a season from May to August. This has led to stabilising ofannual landings and also played a part in Sampling building up a sounder fishery in the 1980's, both in terms of increased LPUE and increased size and value of Size compositions are based on 60-80 sampIes of animals landed (Figures 5.2.3 and 5.2.4 and Tables 5.2.1 200-300 individuals each per year. These are then and 5.2.3). weighted by landings recorded from fishermen's log books; 10 major fishing rectangles are represented. An Over the period 1980 to 1987 landings remained rather annual catch composition is thus derived. 11 Input Parameters lanl1ings reflectel1 an increase in effort by Nephrops trawlers but LPUE remainel1 at a low level (Table Input parameters are given in Table 5.1.3, these were 5.4.2). A comparison between singleand multi rig LPUE unchangel1 from the values usel1 last year. data is given in Table 6.4 anl1 the possible effects ofgear anl1 vesselllP changes in this fishery are fully discussel1 Length Basel1 Assessment in Section 6 (see also Figure 5.4.3 for a comparison of uncorrectel1 LPUE with LPUE correctel1 for HP The al1l1ition of one more year's length l1ata to the changes). The mean size of males and females in trawl average l1istribution usel11ast year prol1ucel1liule change landings has remainel1 fairly eonstant (Table 5.4.3). A so the LCA was not repeatel1. longer time series of landings, effort and LPUE data are shown in Figures 5.4.1 to 5.4.3. Age Basel1 Assessment Assessments Details of the most recent age basel1 assessment for Icelanl1 is given in Section 4.. Sampling Catch Options The length eomposition of eommercial trawl and ereel landings was obtainel1 by monthly sampling (average of Figure 5.2.5 shows plots of lanl1ings vs effort anl1 vs 5 boats per month) at the ports of Ullapool and Loch LPUE (yr-l). Details ofthe prel1iction earriel1 out l1uring inver. Landings and discard data were also collectel1 on the assessment of the Icelanl1ie stock are given in Section board commercial trawlers for the 1st, 2nd, and 4th 4.4. quarters. This landings data was usel1 to supplement port sampling. The trawl landing and discard sampies were 5.2.2 Summary of Management Area Va (Area A) raisel1 to fleet level and combinel1 to estimate total removals, assuming a discard survival of25%. A similar Managel1 by national TACs, further al1vice not given. procel1ure was followel1 for 1990 data. In the absence of reliable discard data for earlier years an average was 5.3 Management Area Vb (non EC) (Area ß) estimatel1 from the combined 1990 and 1991 data and this was appliel1 retrospectively to landings data in earlier Functional Units - Faroes (2) years. In the creel fishery it was assumel1 there were no discarl1s. 5.3.1 Farocs (Functional Unit 2) Input parameters Information on lanl1ings, effort anl1 LPUE of the Faroese ereel fishery is given in Table 5.3.1. These figures are All input parameters remainel1 the same as in previous reprol1ucel1 from the 1990 Working Group report since years (Table 5.1.3). The same parameters were usel1 for upl1atel1 eatch statistics for 1990 were not provil1el1. the trawl and creel components of the stock. 5.3.2 Summary of Management Area Vb (non EC) Length basel1 assessment (Area ß) A eomparison of 1990 and 1991 data showel1 some Managel1 by national TACs, further al1viee not given. differences in the length composition of the trawl discards. A length basel1 assessment was therefore • 5.4 Management Area VIa (Area C) carriel1 out on this stock. The revised reference period was 1980-1991. Output from the LCA is given in Tables Functional Units - North Minch 11 5.4.4 anl1 5.4.5. The LCA results were very similar to South Minch 12 those in the 1991 Report. Annualized fishing mortalities Firth of Clyl1e 13 (averagel1 across the lower 75 % of the length range) were 0.348 and 0.045 for males and females respective 5.4.1 North l\linch (Functional Unit 11) ly. The long term Y/R eurve for males (Figure 5.4.4) was virtually flat toppel1, with eurrent F elose to Fmu' Landings. effort. LPUE. menn size suggesting fishing effort should be maintainel1 at current levels. The Y/R relationship for females was virtually Landings data were rerorted from U.K. vessels alone. linear. 1991 lanl1ings were 2784 tonnes representing a small increase comparel1 to the previous year. 80 % of the Age based assessment landings were by Nephrops trawler,l6 % by creet and 4 % by other trawl methol1s (Table 5.4.1). The rise in A multi-fleet approach was adoptel1 incorporating data 12 .- for the Scottish trawl and creel fishing units in the years reported in the 1991 Report. The VPA gave reasonable 1980-1991. results for the males and indicated that mean F had fallen since 1988. The VPA also suggested that TSB of the Males: males had risen in the early 1980's and then fallen (Table 5.4.10) and further analysis revealed a high correlation The slicing procedure generated 11 'nominal age' groups between male TSB and overall LPUE (Table 5.4.2) (11 = plus group). Catch and weight at age data are (r=0.758, P Females: Landings. effort. LPUE. mean size The slicing procedure gave 14 'nominal age' groups (14 Landings data were reported from U.K. vessels alone. = plus group). Catch and weight at age data are given in 1991 landings of 4207 tonnes were similar to the previ Tables 5.4.11 and 5.4.12. Tuning of input F was carried ous year remaining at a high level (Table 5.4.16). 82 % out as for males. The variances were re1atively high oflandings were by Nephrops trawler, 11 % by creel and compared to mean F. F at age and numbers at age are 7 % by other trawl methods. Fishing effort by Nephrops given in Tables 5.4.13 and 5.4.14 respectively. Much trawlers also remained high (Table 5.4.17). Over the lower fishing mortalities resulted than in the case of reference period LPUE has fluctuated but was currently males (Table 5.4.8). Annual mean F values were at a low level (Table 5.4.17). A comparison between calculated over ages 3-11 (Table 5.4.15) and these values LPUE data of single and multi rig Nephrops trawlers in are plotted against trawl effort data in Figure 5.4.5. The this fishery is given in Table 6.4. In terms of hours correlation coefficient between mean F ami effort is not fished the proportion of effort using multi rig gear in statistically significant (r=0.281). The VPA appears to 1991 was about 10 %. The mean sire of males and have performed badly in the case of females and this females in trawllandings has fluctuated without obvious may account for the much larger TSB estimates in trend (Table 5.4.18). Langer time series of landings, females (Table 5.4.15) compared to males (Table effort and LPUE data are shown in Figures 5.4.1 to 5.4.10). It should be remembered however that higher 5.4.3. female biomasses are consistent with the much lower • mortality rates. Assessments There was some discussion about whether the two fleet Sampling approach was necessarily the best way to assess this fishery. Although the trav·..1 ami creel fisheries exist in The Length composition of comrnercial trawl and creel e10se proximity, for much of the year they are exploiting landings was obtained by monthly sampling (6-7 boats different parts of the stock and in future separate assess per month) at the port of Mallaig. Landings and discard ments might be better. In addition, it might have been data were also collected on board comrnercial trawlers better to use different growth curves for slicing the for the 1st, 2nd, and 4th quarters. This landings data was length composition of the two components of the stock used to supplement port sampling. The landing and but this was not attempted at this Working Group. These discard sampIes were raised to trawl fleet level and points would be addressed in the future. combined to estimate the total removals as described for the North Minch. In the creel fishery it was assumed Catch options there were no discards. The LCA results for males suggested that the exploitation rate over the assessment period was elose to optimum, as 13 -. Input parameters and recruitment remained fairly constant. Compared to males the TSB estimates for females are larger (roughly All input parameters remained the same as in previous bya factor of2) and numbers in the early age groups are years (Table 5.1.3). The same input parameters were also much larger in females. used for the trawl and creeI components of the stock. Catch Options Length based assessment The LCA results in last year's Report indicated that this The reference period for last year's LCA was stock should derive long term benefit from a reduction in 1985-1990. When 1991 data were incorporated the length fishing effort. Fishing effort remains high though the composition of the removals was little different from VPA estimates of annual mean F in males were not previously and a repeat of the LCA was deemed unnec particularly high in comparison with some other Scottish essary. The LCA results in the 1991 Report suggested stocks (eg.the Firth of Forth). These results should that current F on males was weil above FmaJt' perhaps be regarded as prelirninary in view of the poor correlation between mean F and trawl fishing effort in Age based assessments males, other inconsistencies between VPA outputs for males and females and earlier comments regarding the A multi-fleet approach was adopted using data for the suitability of the multi fleet approach (Section 5.4.1). Scottish trawl and creeI fishing units in the period Bearing these points in rnind the Working Group saw no 1980-1991. reason to change the advice given in the 1991 Report. This Offered two options (1) to hold effort at the average Males: level for the reference period or preferably (2) reduce effort by 20%. The slicing procedure produced 11 'nominal age' groups (11 = plus group). Catch and weight at age data are From Table 5.4.17 the average effort by Nephrops given in Tables 5.4.19 and 5.4.20. Tuning of the VPA trawlers over the updated reference period (1985-1991) was carried out using Nephrops trawl effort data and is estimated to be 128.1 thousand hours. A 20% redue historical F was included (Table 5.1.4 summarises input tion in effort would bring this do""TI to 102.5 thousand choices). The variances were small relative to the hours. The equivalent Nephrops trawllandings, predicted estimates of mean input F. using the relationship given in Table 5.1.5 and sho""TI in Figure 5.4.8, are 3255 and 2883 tonnes respectively. An F at age amI number at age estimates from the VPA are equation to raise these landings to the whole fleet, given in Tables 5.4.21 and 5.4.22 respectiveIy. Annual derived from the data in Table 5.4.16 is as folIows: mean F was calculated on age groups 3-8 (Table 5.4.23) and these values are plotted against trawl effort in Figure Totallandings = 0.99 * Nephrops Trawl + 798.4 5.4.7. The correIation coefficient between annual mean Fand effort was not significant (r=0.480) suggesting This equation gives total fleet landings of4021 and 3653 that the VPA has not performed particularly weil. Table tonnes respectively for the two eatch options. 5.4.23 suggests that mean F, TSB and recruitment have varied relatively little since 1881. 5.4.3 Firth or ClJde (Functional Unit 13) Females: Landings. effort. LPUE. mean size • The slicing procedure generated 14 'nominal age' groups Landings data were reported from U.K. vessels alone. (14 = plus group). Catch and weight at age data are 1991 landings were 3031 tonnes, slightly higher than the given in Tables 5.4.24 and 5.4.25. Tuning of input F previous year. 94 % of the landings were made by was carried out as in the males. The variances were Nephrops trawler, 5 % by other trawl methods and 1% by ralher large compared to the low values ofmean input F. ereel (Table 5.4.29). Fishing effort by Nephrops trawlers F at age estimates and numbers at age are presented in increased to its highest level since 1986 but LPUE Tables 5.4.26 and 5.4.27 respectively. Annual mean F remains low (Table 5.4.30). Use of multi rig trawls was calculated over age groups 3-11 (Table 5.4.28). The accounted for around 27 % of the hours fished by estimates of mean F are very low in comparison with Nephrops trawlers (Table 6.4). The mean size of males males. The relationship between mean F amI trawl effort and females in trawl landings appears to have fluctuated data sho""n in Figure 5.4.7 was significant (r=0.733, without an obvious trend (Table 5.4.31). A longer time P 14 , .' . Assessments trends in other indicators of stock comlition. Sampling Females: The length composition of commercial trawl landings The slicing procedure gave 14 'nominal age' groups (14 was obtained by monthly sampling at the Clyde ports of = plus group). Catch and weight at age data are given in Ayr, Campbelto\\ Length based assessment The updated LCA produced similar results to those in the 1991 Report and suggested that fishing effort on the male A Comparison of 1990 and 1991 data showed differences component was above Fmax• The VPA results were in composition of the trawl discards. The length based difficult to interpret and it is worth noting that several assessment was therefore repeated for this stock. The approaches tried by the 'Methods' Working Group also reference period was 1988-1991. Output from the LCA produced inconsistent results when applied to data for the is given in Tables 5.2.32 and 5.4.33 for males and Clyde stock (Anon., 199Ib). The 1991 Nephrops Work females respectively. Despite discard differences, the ing Group Report drew attention to the difficulties of LCA results were nevertheless very similar to those sampling adequately this heterogeneous stock. given last year (Anon, 1991a) Annualized fishing mortal ities (averaged across the lower 75 % of the length range) In last year's Report the Working Group recommended were 0.351 and 0.026 for males and females respective that fishing effort should be held at the 1990 level, which Iy. The long term Y/R curve for males (Figure 5.4.9) for Nephrops trawlers was 153.4 thousand hours fishing. was fairly flat-topped and suggested that current F was Since then 1991 effort by this component of the fleet has about 20% above Fmax. For females the YIR relationship increased and, as Table 5.4.30 shows, LPUE is currently was virtually linear. at a very low level. The recommendation ofthe Working Group is again that fishing effort should be held at the Age based assessment 1990 level. Nephrops trawler effort of 153.4 equates to landings of 3262 tonnes using the linear relationship Males: between landings and effort given in Table 5.1.5 and shown in Figure 5.4.11. An equation to raise these • A single fleet assessment was carried out using Scottish landings to fleet level using the data in Table 5.4.29 is as data from 1980-1991. The slicing procedure generated II folIows: 'nominal age' groups (lI = plus group). Catch and weight at age da ta are given in Tables 5.4.34 and 5.4.35. Total landings = Tuning of the VPA was carried out using trawl effort 1.039 * Nephrops trawllandings + 94.1 data amI historical F was included (see Table 5.1.4 for inputs). The variances were small relative to the value of This gives recommended total fleet landings of 3485 input F. F at age and number at age are given in Tables tonnes. 5.4.36 and 5.4.37 respectiveIy. Mean F was calculated over ages 3-8 (Table 5.4.38) and the values are plotted 5.4.4 Summary ror Management Arca VIa (Arca C) against trawl fishing effort in Figure 5.4.10. The correla tion between mean Fand effort was not significant The recent landings in F.U. 11, 12, 13 and other ICES (r=0.252, P>0.05) suggesting that the analysis had not rectangles forming Management Area C are given by performed weIl. The VPA results suggest that mean F unit in Table 5.4.44 and by country in Table 5.4.45. The increased sharply in 1988-1990 (Table 5.4.38); the catch options for the area as a whole are provided by the analysis is probably too unreliable to make comments on addition of those for each Functional Unit together with 15 697 tonnes for other rectangles (the maximum recorded, Effart and LPUE see Table 5.4.44). For eonvenienee the derivation of the Area options is set out in the text table below. Overall Table 5.6.2 gives the available Swedish effort data for option 2 allows for a eut in effort in the South Mineh. the Skagerrak sinee 1982. Effort data are available for an overall period 1978-1991 and in the two recent years FU Derh'ation or option Total they have been separated for single trawl and twin trawl landin~s (see Section 6.3). The increase of twin trawl effort (t) (130% in 1990-91) and the eonversion of twin trawl LPUE to single trawl LPUE implies that total Swedish 11 Av. landings 1981-91 3372 Skagerrak standardised trawling effort (as single trawl 12 1) av. effort 1985-91 1) 4021 units) has inereased by 250% from 40000 to 140000 2) 80% of 1) 2) 3653 trawling hours per year during the last ten years (see Figure 5.6.2). Danish effort data (Table 5.6.3) are 13 1990 effort level 3485 available for the period 1987-1991 and are assumed to be Other rec- max. recorded 697 mainly twin trawl effort for the whole period. The tangles estimated Danish effort (days trawling) in Skagerrak fluetuates between 15000 to 22000 with no clear trend Total 1) 11575 during the periou. 2) 11207 LPUE in both the Danish and Sweuish Skagerrak fishery has decreased in 1991. The Swedish LPUE shows a clearly falling trend during the recent ten year period (Table 5.6.2, Figure 5.6.3) 5.5 l\Ianagement Area Vb (EC) and Vlb (Arca D) 5.6.2 Kattl'gat (Functional Unit 4) Funetional Units - None undings 5.5.1 SummaQ' for l\Ianagement Area Vb (EC) and From 1982 to 1987 the total landings have fluctuated Vlb (Arca D) between 1 500 and 2 000 tonnes (Table 5.6.4). In the period after 1987 (especially in 1988) the south eastem Zero TAC to prevent misreporting Kattegat suffered from severe hypoxie eondition and the landings were markedly lower. Totallandings for 1991 5.6 l\Ianagement Arca lila (Arca E) were the lowest during the recent ten year period. The affected Nephrops grounds in south eastem Kattegat Funetional Units - Skagerrak (3) seems not to have recovered ano the Nephrops fishing Kattegat (4) fleet is still mainly loeated in the northem parts of the Kattegat. A longer time series of landings is sho\\n in 5.6.1 Skagerrak (Functional Unit 3) Figure 5.6. I. undings. Bffart and LPUE Total Skagerrak landings have inereaseu by about 100% Danish effort oata are available for 1987-1991 (log book • during the reeent 10 year periou (Table 5.6.1 anu the uata, see Table 5.6.5). Total effort is estimated from landings in 1991 are the highest recordeu. Denmark and LPUE and landings. Danish effort is fluetuating with the Sweden dominate the Nephrops fishery in the Skagerrak lowest value in 1988 being a eonsequenee ofthe hypoxie (55 % anu 38 % of the total landings respeetively ). The eondition. Swedish effort and LPUE data are available Norwegian fishery has inereased from 70 to 194 tonnes from 1978 to 1991 (the series from 1982 is sho\\n in in reeent 2 years but is still rather insignifieant (7 % of Table 5.6.6). The single trawl effort was slightly inereas total landings). The lanuings from the Swedish ereel ing until 1987 and falling from 1989 and onwards while fishery have inereased from 110 tonnes in 1990 to 151 the effort with twin trawl inereases. The standardized toimes in 1991 whieh is the highest reconlcu so far. For total effort is stable ouring the period except for a small management purposes it would seem reasonable to assess increase in 1991 (Figure 5.6.2). LPUE for the Swedish this fishery separately, when adequate data are available. single trawlers shows a decreasing trend during the Long term trends are given in Figure 5.6. I. recent ten years (Table 5.6.6, Figure 5.6.3). 16 Mean lenglh in c~tch (Skagerrakaml Kattegat comhinedl Age based assessment Tbe mean length in the catches has decreased from 40.4 The Working Group considered that age based assess mm (carapace length) and 39.7 mm for males and ment is useful for stocks with five or more years ofdata. fe males respectively in 1990 to 38.7 mm and 37.3 mm In the case of Skagerrak and Kattegat only two years of respectively in 1991. During the third and fourth quarters length distributions were available so age based assess in 1991 Danish length data were also sampled giving ments were not carried out on this stock. mean sizes in the total catches in Skagerrak and Kattegat of 36.5 mm for males and 36.0 mm for the females. Catch Options Tbe size distribution of the total catch of both males amI Table 5.1.5 and Figures 5.6.6 and 5.6.7 show separate females (Figure 5.6.4) shows that the current minimum Iy, relationships between landings and effort for the landing size (MLS), applied in conjunction with a mesh Skagerrak and Kattegat. Owing to the comhined assess sire of 70 mm diamond mesh, results in a large catch of ment of these two stocks, a potentially more useful undersized Nephrops. These are discarded and a high relationship is that of combined totallandings (shown in mortality on them is likely. Table 5.6.9 and by country in Table 5.6.10) against relative effort. Tbe plot and relationship are shown in Assessments (Sb!!errak and Kattegat comhinedl Figure 5.6.8. Sampling As in the previous year the Working Group considers the LCA made for the lila stock is too uncertain (being Tbe length frequency data (Swedish Skagerrak data based on only two years of data) to provide a reliable available for 1990-1991 and Danish Skagerrak and basis for any catch option. • Kattegat data available for 1991) were raised to total landings from Skagerrak and Kattegat combined. Tbe Figure 5.6.8 however, indicates alinear relationship. average length distribution of the two years provided the According to this, the present effort level should result basis for the LCA. Sweden sampled landings and in maintaining the present level of landings of approxi discards throughout the year and Denmark sampled mately 4000 tonnes. catches in the later half of the year. 5.6.3 Summary for Management Area lila (Area E) Input parameters Tables 5.6.9 and 5.6.10 show the landings for this Tbere is still no information on the growth parameters Management Area by Functional Unit and Country. from the Skagerrak-Kattegat area so the input growth parameters (L.. and K) were based on the corresponding The Working Group is of the opinion that the LCA for parameters for the Nephrops stocks in IVa, also taking both males and females are probably too uncertain to into account the observed maximum length in the base any management recommendations on, since the sampIes. Natural mortality was set to 0.3 for males and resuIts seem to be very sensitive to relatively small 0.2 for females. All length groups were assumed to changes in the growth parameters, which themselves are represent mature individuals. All input parameters were not based on any growth investigations in lila, hut have the same as last year, details given in Table 5.1.3. been taken from Nephrops stocks in IVa. • Tbe large amount of undersized Nephrops in the lila Length Based Assessment catches does not necessarily reflect any overexploitation Output from the LCA is given for males and females in ofthe stock, but may only reflect that the MLS is set too Tables 5.6.7. and 5.6.8. The mean F across the lower high in relation to current legal mesh sire with standard 75 % of the length distribution for males and females are diamond shaped meshes. Tbe situation should be careful similar to last year (0.29 and 0.12 respectively). Tbe Iy monitored. assessment for males indicates an increase ofabout 10 % in long term yield if effort is reduced by 40 %, while a In view, however, of the increased Swedish effort in slight (2 %) increase in long term yield for the females recent years, and the simuItaneous marked reductions of is obtained by a reduction of ahout 20 % in effort both the Danish and Swedish LPUE (Tables 5.6.2- 5.6.3 (Figure 5.6.5). For both sexes, stock biomass per recruit and Tables 5.6.5 and 5.6.6) in 1991 the Working Group increases ifeffort is reduced. This assessment appears to recommends that if a TAC is to be set, it should not indicate that both males and females are slightly more allow any further increase in total effort. Following the exploited than in last year's assessment. relalionship hetween effort and landings (Figure 5.6.8) the total landings recommended should then be about 4000 tonnes. 17 5.7 l\Iana~cmcnt Arca IVa 44-48 E6·E7 + 44E8 weight at age data are given in Tables 5.7.4 and 5.7.5. (Arca F) Tuning of the VPA was carried out using Scottish Nephrops trawl effort data and historie F (Table 5.1.4 Functional Units - Moray Firth (9) summarises the input choices for tuning). The varianees Noup (10) were relatively smaIl eompared to the tuned value of F. F at age and number at age are given in Tables 5.7.6 and 5.7.1 l\Illray Firth (Functillnal Unit 9) 5.7.7 respectively. Annual mean F values were calcu lated for ages 3-7 (Table 5.7.8) and are plotted against Landings. effort. LPUE. me:m si7e effort data in Figure 5.7.1 .This relationship is signifi cant (r=0.764, P Length based assessment The LCA results on males given in last years report • suggested that exploitation was e10se to optimum and the A comparison of 1990 and 1991 data showed little recommended management option was to hold fishing difference in length composition of the landings amI effort at the average level over the reference period discards so the LCA was not repeated. The LCA results (1985-1990). Effort and landings have since fallen so the last year showed that the YIR curve for males was flat Working Group saw no need to change the advice given topped with current F e10se to FllWJ(' In females the YIR last year. The catch option has been recalculated by relationship was virtually linear. including 1991 effort data and averaging over the extended reference period (1985-1991). From Table Age based assessment 5.7.2 the average fishing effort by Nephrops trawlers is ca1culated to be 58.2 thousand hours. Tbis level ofeffort Males: equates to landings of 1732 tonnes, using the linear relationship between landings and effort in Table 5.1.5 A single fleet assessment was carried out using Scottish shO\'IO in Figure 5.7.2. These landings were then raised data from 1980-1991. The slicing proceuure generaled 9 to the whole fleet level using the following relationship 'nominal age' groups (9 = plus group). Catch and (derived from data in 5.7.1): 18 Totallandings = 1.18 ... Nephrops trawler landings -32.3 5.8.1 Fladen Ground (Functional Unit 7) The revised catch option for the Moray Firth is therefore Landings, effort. LPUE and mean size 2012 tonnes. Landings data were reported by Seotland and Denmark. 5.7.2 Noup (Functional unit 10) In 1991 there was a large increase in landings, to 4241 tonnes, of which nearly 3800 tonnes were landed in Landin!!s. effort, LPUE, mt':ln size Scotland (Table 5.8.1). This increase reflected a marked rise in effort by UK Nephrops trawlers (Table 5.8.2), a Landings data were reported by Scotland. 1991 landings major proportion ofwhich were large vessels using multi from this small fishery were 196 tonnes of whieh 110 rig trawls (see Table 6.4). This partly accounts for the tonnes were taken by Nephrops trawlers (Table 5.7.14). high LPUE (TabIe 5,8.2) compared to other grounds LPUE has fluctuated without obvious trend (Table around Scotland (Figure 5.4.3). In Scottish landings the 5.7.15) mean sire appears to have increased recently in males and fluctuated in females without obvious trend (TabIe There is no mean size or length composition data for the 5.8.3). stock and no assessments were possible. Assessments Catch Options Sampling The relationship between lamlings and effort is shown in Figure 5.7.3. The maximum landings in the reference In 1991 length composition data were obtained by period (1990, 217 tonnes) \\fere considered appropriate irregular sampling (in only 4 months of the year) of the for this stock. landings at the Scottish ports of Fraserburgh and Peter head. No discard sampling was carried out for this stock 5.7.3 Summary for l\Iana~ement Area IVa 44-48 and therefore, for the purposes of the assessments, 1991 E6-E7 + 44E8 (Area F) Moray Firth discard data was used. The recent landings in FU 9,10 and other ICES rec Input parameters tangles forming Management Area F are given in Tables 5.7.16 and 5.7.17. The same input parameters were used as previously (Table 5.1.3). To obtain the appropriate cateh option for this Manage ment Area the recommended landings for the Moray Length based assessments Firth estimated aecording to the procedure outlined in Section 5.7.1 should be added to the maximum landings A comparison between the length composition of the for the Noup and for the 'other reetangles' as set out in removals used in last years LCA and that obtained after the text table below: updating with 1991 data showed little difference so the LCA was not repeated. In addition, the very large FU Derhalion of option Total increase in effort means that the stock is unlikely to be landin~s in a steady state. The YIR analysis in last years report (t) suggested that F was slightly above Frnax in males and • a little below Fmax in the case of females. 9 Av. effort 1985-91 2012 10 max. (1990) landings 217 Age based assessments Other max (1990) landings 69 A multi fleet approach was adopted incorporating the Total 2298 Scottish and Danish fisheries. No length composition or effort data were available for the Danish fleet so Scottish data were used and raised to Danish landings. Scottish data were available from 1980 - 1991. Landings in the 5.8 l\Ianagement Area IVa Remainder (Area G) Danish fishery were only recorded since 1986 (Table 5.8.1). Functional Units - Fladen (7) Males: The slicing procedure produced 8 'nominal age' groups (8 = plus group) . Catch and weight at age data are 19 given in Tables 5.8.4 and 5.8.5. Tuning ofthe VPA was P Females: 5.9 l\Ianagement Arca IVh,c East or 10 East (Arca 11) The slicing procedure gave 13 'nominal age' groups (13 = plus group). Catch and weight at age data are given in Funetional Units - Botney Gut-Silver Pit (5) Tables 5.8.9 and 5.8.10. Tuning of input F was carried out as for males (Table 5.1.4). In females the variances 5.9.1 Dolney Gut - Sih'er Pit • were larger, comparable in magnitude to the values of tuned input F. F at age and number at age are given in Landings. effort and LPUE Tables 5.8.11 and 5.8.12. Mean F was calculated on ages 3-8 (Table 5.8.13) and plotted against effort data in Over the past six years total international landings from Figure 5.8.1. This relationship was significant (r=O. 832, the Botney Gut - Silver Pit area rose from about 380 P 20 report (Anon; 1991a) this apparent drop in LPUE should The same holds for the sex-ratios by size-class (see in part be auributed to a lack of precision in the effort Figures 5.9.3 and 5.9.4 for representative examples). data base. In October-December 1990 and again in 1991, Several hypotheses can be advanced to explain this the Nephrops catches in the Botney Gut - Silver Pit area increase in catchability, such as major changes in the were rather poor, and many vessels diverted part of their periodicity of the reproductive cycle or in external, effort to other fishing grounds in the Southern North Sea environmental conditions, but all of these need further and the English Channel. The Belgian effort statistics investigation. however do not allow discrimination between effort spent in different areas during the same voyage. As a conse Mean sizes quence the effort figures for the 4th quarters of 1990 and 1991 are exaggerated as compared to the Nephrops Mean sizes of Nephrops landed are available for the landing figures, which resulted in extremely 10w LPUE Be1gian fleet only. Owing to the peculiar discarding values for these two periods (viz. 3.4 ami 3.1 kglhour practice on the Belgian Nephrops trawlers (see Anon, fishing), and in pushing down the yearly average. 1990 for further information) mean sires are given for the market categories "small" and "medium plus large" From data provided by the skippers of these vessels it separately. appeared that - particularly in these two quarters - they spent only between 1/3 and 1/4 of their time and effort The mean sires of "small" males and females remained in the Botney Gut - Silver Pit area. Taking this into fairly stable over the last 10 years, at values between account would bring the average LPUEs for 1990 and 30.0 and 33.0 mm for both sexes (Figures 5.9.5 and 1991 to about 9.3 and 7.4 kglhour trawling (Table 5.9.6). 5.9.2). The mean sizes of "medium plus large" males slightly Composilion of the landingc; decreased in 1991 to values between 37.0 and 43.0 mm, after having been at 39.5 - 43.0 mm in 1989 and 1990. The composition of the Nephrops landings from the The same holds for "medium plus large" females, which Botney Gut - Silver Pit stock drastically changed over the showed a similar decrease in mean sire, from 39.5 last few years. In 1986-88 the bulk of the landings, 44.0 mm in 1990 to 37.0 - 42.0 mm in 1991. (70-75% in numbers and 75-80% in weight), consisted of males. Since 1989 however, the proportion of females in Assessmentc; the landings almost doubled (Figure 5.9.1). The increase in the landings from 1988 to 1989, and again from 1989 Sampling levels and Input data to 1990 could be fully aUributed to the increase in the numbers and weight of females landed. Reference period: 1986-1991 (for both length and age based assessments). The sex-ratio ofNephrops catches and landings is kno\\n to vary seasonally (Figure 5.9.2), in connection with the Length frequency data are currently being collected from egg-bearing condition of the females. During winter, market sampies of the landings by Belgian Nephrops when most females are berried and hiding in their directed otter trawlers only. Sampies are taken every two burrows, the landings mainly comprise males, whereas weeks, and consist of 100 animals per market category. during summer, when the majority of the females are On average about 6,000 Nephrops are being measured • non-berried, the landings may consist of up to 80 % of (CL to nearest 0.5 mm) every year. Length compositions females, depending on the size-class (Figures 5.9.3 amI of the landings were calculated from these market 5.9.4). Any change in the seasonal distribution offishing sampies, weighted by season and market category, and effort therefore is likely to ret1ect on the overall sex raised to total international landings. Estimated length composition of the catches and lamlings. compositions of the discards were obtained using the same technique as for the previous assessments (see Over the years 1986-91 there have been some changes in Anon, 1990a for further information). the seasonal distribution of fishing effort, but these are far too small to explain the observed increase in the Input parameters numbers of females lande 21 same level in 1986-88), and because of the ehanges in mueh more diffieult to explain, especially in view of the exploitation pattern of the females, whieh also their increased availability to trawling in the most recent became apparent from 1989 onwards, additional LCAs years. were run with the data for 1986-88 on the one hand, and for 1989-91 on the other. Age based assessment Input values for M, L..,K and terminal F were the same Multi-fleet VPAs (involving Belgium and Denmark) were as in last year's assessment. Full details ofinput parame run for males and females separately, with "nominal" age ters are given in Table 5.1.3 distributions of the removals for 1986-91. Age distribu tions of Nephrops removed by the Belgian fleet were Length based assessment calculated from the length distributions of the actual landings, plus 75 % of the estimated discards at length, Output from the LCAs for males and females are given assuming 25 %discard survival. Removals by the Danish in Tables 5.9.3 and 5.9.4. Mean Fs generated by the fleet were estimated, under the assumption that their LCA were 0.19 for the males and 0.08 for the females. length composition was similar to that ofthe removals by The results of the Y/R and B/R analysis show that the Belgian fleet. eurrent Fs are slightly below Fmax for the males and weil below Fmax for the females (Figure 5.9.7). The predieted Slicing of the length compositions into age groups was long-term gain in landings upon an inerease in effort done using the melhod described in Section 4.3 • The from eurrent F to Fmax is very smalI, espeeially for the lower boundary of nominal age group 1 corresponds to males (about 2.5 %). a size of 24 mm, for bolh males and females. The number of 'nominal age' groups was set at 13 for males, Outputs from the LCAs for the three year periods and 16 for females, the oldest age group being a plus 1986-88 and 1989-91 are summarized in Tables 5.9.5 group. and 5.9.6 for the males and in Tables 5.9.7 and 5.9.8 for the females. Mean Fs, ealculated over the lower 75 Effort data were available for the Be1gian Nephrops % ofthe length ranges are given in the text table below: directed fleet only (see Table 5.9.2). Initial tuning runs, including historical F, revealed c1ear time-trends in effort Males Females and F. Final runs for males and females therefore excluded historical F. Table 5.1.4 summarises input for Referenee period 1986-88 0.19 0.11 tuning. Referenee period 1989-91 0.19 0.07 Males: Referenee period 1986-91 0.19 0.08 Catch at age and weight at age for the males are given in Tables 5.9.9 and 5.9.10 respectively. Tuned Fs ranged Mean Fs for the females c1early deereased from 1986-88 between 0.38 and 0.61, and were highest in the age to 1989-91, whereas those for the males remained groups 4 and 5 (0.6108 and 0.6122). Varianees around eonstant. Both sets of means however mask some F were generally small as compared to the actual values important size-related changes in fishing mortality. of tuned F. F at age and number at age are given in Tables 5.9.11 and 5.9.12. Values of F tend to be highest Combined plots of F against size, for each of the above in the age groups 4-8, although this pattern is not equally reference periods, are given in Figures 5.9.8 and 5.9.9 evident in all years. The age-wise values of F c1early • for males and females separately. As can be seen from increased over the time series, especially from 1987 these graphs, F increased from 1986-88 to 1989-91 for onwards. In most age groups they roughly doubled males within the size range 30-38 mm, but decreased for within the next 3 or 4 years. males ~ 44 mm. For females an inverse trend can be noticed, with substantial decreases in F for the size Fbar (2-10) went up gradually with increasing effort, c1asses 30-40 mm, and a slight inerease for the largest from 0.2286 in 1986 to 0.5289 in 1991 (Table 5.9.13). size-c1asses. The regression of Fbar on effort, as shown in Figure 5.9.12. is highly signifieant. For the time being the The results of the YIR and B/R analysis suggest that available time series is considered to be too short to current F is getting eloser to Fmax for the males (Figure make any commenls on trends in total stock biomass, 5.9.10), amI further bdow Fmax for the females (Figure spawning stock biomass or recruitment. 5.9.11). The result for the males seems to be in line with the trend in effort, which was predicted to give only Females: slightly larger lamlings for substantial increases in effort (Anon, 1990a and 1991a). The output for the females is Catches at age and weights at age for female Nephrops 22 are given in' Tables 5.9.14 ami 5.9.15. Input tuning 5.10.1 Farn Decps (Functional Unit 6) options were as for males. Tuned Fs ranged between 0.030 and 0.065, i.e. wel1 beIow input M, and were Landings and Catches highest in age group 9, (0.0653). Variances around F were mostly much larger than the corresponding values Landings from this unit (Table 5.10.1) are made mainly oftuned F. by UK vessels. Tbe totallandings have again decreased from the peak of 3099 tonnes in 1989 to 2061 tonnes in Values of F at age and number at age are given in Tables 1991, below the average landings of 2248 tonnes during 5.9.16 and 5.9.17 respectively. In general, fishing the last 10 years. As the main fishing season occurs from mortalities seem to have increased over the past three or Gctober to March the data for catches and other statistics four years, but this trend is not equal1y elear in al1 age have been based on seasons for the year ending 30th groups. Fbar (2-13) increased from 0.0264 in 1986 to June. Because of the "carry-over factor" from previous 0.0562 in 1990, then slightly decreased to 0.0549 in calendar years, the landings by season in Table 5.10.2, 1991 (Table 5.9.18). Fbar was found to be correlated and the long term trend shown in Figure 5.10.1 still with fishing effort (Figure 5.9.12), but because of the indicate an increasing trend for the last recorded 1990/91 large variances around tuned F there is serious doubt on season. the significance of this relationship. Discard sampling has been reduced so that data is only Catch option<; available during the peak ofthe fishing season in Novem ber, and estimates of the annual catches are no longer Relationships bet\\:een landings and effort, and between available (Table 5.10.2). landings and LPUE(t-l) are given in Table 5.1.5 and shown in Figure 5.9.14. Correlations are poor, with values of r be10w 0.3, actually meaning that the relation ships are of little use for predictive purposes. Tbe fishing effort recorded for UK trawlers (Table 5.10.2, long term trends Figure 5.10.2), which has Tbe conc1usions from the LCA are in line with last shown a steady threefold increase over the past 10 year's and seem to be confirmed, at least for the males, seasons, has final1y come to a halt with a slight reduction by the age based assessment. from the previous season to a level of 127000 hours fished in 1990191. Tbe recent increase in fishing errort pushed current F on the males up, c10ser to F""",' Even though, as yet, there LPUE/CPUE is no evidence of over exploitation of the Botney Gut Silver Pit stock, there seems to be very little room left Because of the reduction in discard sampling annual for any further increases in erfort. Therefore the Work CPUE is no longer available. Tbe LPUE (Table 5.10.2 ing Group reiterates its recommendation to restrict and Figure 5.10.3) has levelled off in the last six sea fishing erfort to a level corresponding to the 1990 and sons, fluctuating slightly around a mean of 22 kg/h 1991 landings (i.e. 750-760 tonnes). trawling, the same as the long term mean (1966-91). 5.9.2 Summary for Managemcnt Arca IVb,c East Mean Size of 10 East (Area 11) Tbe decline in the mean size ofthe landings over the last Recent landings from Functional Unit 5 and from other 10 years seems to have stopped with mean sizes for both rectangles in Area H are given in Table 5.9.19, and males and females ofaround 32 nun (carapace length) in landings by country in Table 5.9.20. Taking into account the last three seasons (Table 5.10.3). Tbe mean sizes of the catches taken in statistical rectangles outside the the catch are now restricted to estimates for November. Botney Gut - Silver Pit, about 170 tonnes in 1991, would Ir these sampIes are taken to represent mean sizes for the set the overall TAC for the Area at approximately 920 whole season, then they suggest that there has been a tonnes. This is very elose to last years rccommendation reduction in the mean sizes of the catches for both sexes (875 tonnes). from 28.5 nun for the period 1984/85 - 1989190 to 24.9 nun in the last two seasons. 5.10 l\lanagcmcnt Arca IVb,c Wcst of 10 East (Arca I) Assessments Functional Units - Farn Deeps (6) Sampling Levels Firth of Forth (8) Landings are sampled at the most important ports in England on a monthly basis. In the last season 10 and 14 23 sampIes were taken respectively in quarters 3 and 4 of period 1984-90, but similar to the maximum F of 0.57. 1990, and 14 and 9 sampIes were taken in quarters 1 and Tbe plot of mean F(3-7) on effort (Figure 5.10.4) gave 2 of 1991. In addition 10 diseards sampIes were taken at a signifieant correlation suggesting that the VPA was the main port of North Shields in November 1990 at the reasonable. Tbe TSB and recruitment for 1984 to 1990 normal peak of the seasonal landings. seemed reasonably stable, fluctuating without trend. Input Parameters Females: An additional season's length distribution ofthe landings Tbe length compositions ofthe females were split into 14 was available. However, beeause of a reduction in nominal ages and a plus group (15 +) producing cateh at discard sampling, the 1990/91 discards were estimated age (Table 5.10.9) and weight at age (Table 5.10.10). from the average of the period 1986/87 to 1989/90 and Tbese were input to the VPA with the tuning and output adjusted to the 1990/91 landings. Tbe removals for the ehoiees as given in Table 5.1.4. Tbe historie F was period 1984/85 to 1990/91 were estimated using a excluded and a zero weighted mean q used. Tbe tuning discard survival of 0.25. output gave quite low F estimates with fairly high varianees. Tbe F at age and number at age by year Tbe other inputs for growth, maturity, length/weight arrays are given in Tables 5.10.11 and 5.10.12. Tbe relationship, and natural mortality were as used last year mean F(3-1O) values (Table 5.10.13) ranged from 0.07 (see Table 5.1.3). to 0.17, with, in general, an inereasing trend with time. These are somewhat higher than the mean F value of Length Based Assessment 0.08 estimated by the length eohort analysis for the referenee period 1984-90, but less than the maximum F Tbe addition ofthe 19901911ength eomposition to the six of 0.23. Tbe plot of mean F(3-10) on effort (Figure year series used last year was unlikely to influenee the 5.10.4) gave a signifieant eorrelation. Tbe TSB and mean length distribution used in the length eohort recruitment for 1984 to 1990 seemed reasonably stable, analysis. There were no new input biological parameters. fluetuating without trend. Tbe results from last years length based assessments Comparison of males and females: remain valid. These showed that for males reduetions in effort by up to 40 % were predicted to result in modest Tbe mean Fs on males were higher than those on long-term increases in yield up to 10%. By eontrast for females. This is consistent with the greater availability of the females the results predicted higher yields ifeffort is males than females and was also observed in last year's inereased, with Fmax around 50% higher than the eurrent LCA. Tbis is also reflected in the larger TSBs for level eorresponding to a 10% inerease in yield. females (Tables 5.10.8 and 5.10.13). Recruitment of females at nominal age 1 was higher than for males by Age Based Assessment 29%. A 50:50 sex ratio would be expected at this age. As over 99 % of the landings are made by the UK fleet Cateh Options a single fleet assessment was done. Effort data (hours fished) on a seasonal basis were available for the same Although the signifieant (P 24 .------.. landings, with mean effoft for 1986-90 gives a prediction Age based assessment of 2477 tonnes. These figures are both within 1% of the eatch option of 2453 tonnes given last year. A single fleet assessment was carried out using Scottish data from 1981-1991. 5.10.2 Firth of FortlI (Functional Unit 8) Males: Landings. effort. LPUE. mean size The slicing procedure generated 11 'nominal age' groups (11 = plus group). Catch anu weight at age data are Landings data were reported by U.K. vessels only. 1991 given in Tables 5.10.17 and 5.10.18. Tuning ofthe VPA Landings were 1402 tonnes representing a fall of over was carried out using Nephrops trawl effort data (see 500 tonnes compared to the previous year (Table Table 5.1.4 for input ehoices). Historic F was not used 5.10.14). The decline in landings was due to a 28 % fall because ofevidenee ofa time trend. The varianees about in fishing effort (Table 5.10.15) by Nephrops trawlers F were small compared to the magnitude of tuned input (which account for 97 % ofthe fishery) and a 15 % fall in F values. F at age and numbers at age are given in LPUE (Table 5.10.15). LPUE has fallen to its lowest Tables 5.10.19 and 5.10.20. Annual mean F was level since 1975 (Figure 5.4.3). A comparison between ealculated on age groups 3-8 (Table 5.10.21) and these LPUE of vessels using single and multi rig trawls is values are plotted against effort in Figure 5.10.6. The given in Table 6.4. There has been a steady decJine in relationship was highly significant (r=0.95, P In 1991 regular monthly sampling was carried out at the Females: ports of Pittenweem and Eyemouth (average of 5 boats per month). Sampling of trawl landings and discards was The slicing procedure gave 16 'nominal age' groups (16 earried out on board commercial fishing vessels during = plus group). Catch and weight at age data are given in the Ist,2nd and 3rd quarters of the year. This landings Tables 5.10.22 and 5.10.23. Tuning of input F was data was used to supplement the port sampling. The carried out as for the males (Table 5.1.4 for inputs). F trawl landings and discard sampies were raised to fleet at age was very much lower than in males (Table level and combined to estimate total removals. Discard 5.10.24) and the variances on the estimates of input F rates for 1990 and 1991 were averaged and applied were relatively high. Numbers at age are given in Table retrospectively to the landings data in earlier years. 5.10.25. Annual mean F was calculated over ages 3-10 (Table 5.10.26) anu the values are plotted against effort Input parameters in Figure 5.10.6. The linear regression is significant suggesting that the VPA was reasonably weIl behaved. All input parameters remained the same as in previous TSB of the female eomponent was slightly higher than in • years (Table 5.1.3) males (consistent with lower mortalities on the former) and appears to have peaked in the mid 1980's (Table Length based assessment 5.10.26). There was some evidence that the recruitment of females had increased recently. A comparison of 1990 and 1991 data showed little difference in the length composition ofthe discards or of In most years there appears to be reasonable eonsisteney the upuateu removals for the previous reference periou in male and female numbers at the early age groups (1981-90) so the LCA was not repeated. The LCA (Tables 5.10.20 and 5.10.25) results last year gave a YIR eurve for males which • suggested that eurrent F was weil above FIIlllX In females the Y/R relationship was virtually linear. 25 • Catch Options in the text table below: The LCA results for males in last years Report (Anon, FU Derh'ation of option Total 1991a) suggested that the Firth of Forth stock would landings benefit in the long term from a reduction in fishing (t) effort, though the long term gain in yield was expected to be smalI. To achieve this gain the Y/R analysis 6 Av. effort 1986-90 2477 predicted that a 40 % effort reduction would be required 8 1) Av. effort 1981-91 1) 1791 for which the short term loss in yield was expected to be 2) 20 % reduction 2) 1405 about 20%. Other max (1991) landings 386 The management recommendation in the 1991 Report Total 1) 4654 was to achieve some stability in this fishery by maintain 2) 4268 ing fishing effort at the average level for the reference periou (1981-1990). This option is again presented with an update to inc1ude 1991 data (Option 1). The Working Group is now of the opinion that this approach was over 5.11 Management Area VIIa (excluding 33E2 optimistic. Although 1991 effort was elose to the refer 33E5) (Area J) ence period average, landings fell substantially due mainly to a sharp fall in LPUE (Table 5.10.15). The Functional Units - Irish Sea East (14) LCA results earlier showed that annual fishing mortality lrish Sea West (15) was higher on the Firth of Forth stock than on other Scottish stocks amI this has now been confirmed by the 5.11.1 Irish Sea East (Functional Unit 14) VPA. The VPA also revealed a decline in TSB which • correlates weIl with lhe fall in LPUE (Figure 4.3.2) . In Landings view of these results lhe Working Group recommends a 20% reduction in fishing effort relative to the updated The total intemationallandings (Table 5.11.1) from the reference period average (Option 2). eastem Irish sea have nearly doubled from the 10west of the last 10 years - 431 tonnes in 1989, to 837 tannes in Average annual effort by Nephrops trawlers over the 1991. Most of these landings were maue into England, periou was 70.5 thousanu hours which, when reduced by though the majority of them (72% of the directed 20%, gives 56.4 thousanJ hours. Application of these landings in Figure 5.11.1a) are made by visiting Nortb effort levels implies Nephrops trawler lanuings of 1736 em lrish vessels. am11351 tonnes respective1y using the linear relationship between landings and effort (Table 5.1.5 anu Figure The ratio of whole Nephrops to tails (on a whole weight 5.10.7). Nephrops trawler landings are raised to fleet equivalent basis) has decreased to 45:55, but is still level using the following relationship between Total around the 50:50 ratio seen in the last five years. landings and Nephrops trawl landings derived from the data in Tables 5.10.14: Fishing Effort Totallandings = 1.006 * Nephrops trawl + 45.4 Fishing effort in 1991 by directed voyages (ie voyages where Nephrops account for > 25 % by weight of the the catch options for the Firlh of Forth are therefore: landing), which caught 62 % ofthe landings, increased by • 12% on the previous year trawling hours (Table 5.11.2). 1) 1791 tannes; 2) 1405 tonnes (recommended) The effort for English anu Welsh vessels actually fell by 25 %, but this was more than compensated by a 39 % 5.10.3 Summary fur l\lanagl'ment Area IVb,c \\'est increase in the directed effart by Northem lrish vessels of 10 East (Area I) (Figure 5.ll.lb). The recent Nephrops landings in Functional Unils 6 and Landings Per Unit Errort (LPUEl 8 and from other ICES rectangks forming Management Area I are given in Tables 5.10.27 and 5.10.28. Total Compared to 1990 the overall LPUE in 1991, based on landings from the area reached a peak of 5342 tannes in Nephrops directed voyages, increased by 7 % to 27 kglhr 1988 hut have since fallen. The maximum landings in the (Table 5.11.2). The LPUE of Northem lrish vessels fell reference period are considered appropriate for the slightly, while that of English vessels landing into lanJings from 'other' rectangles. Whitehaven increased, hoth being elose to the overall value. Vessels landing into Fleetwood continue to have The catch option for the area as a whole is summarised the lowest LPUE (Figure 5.ll.1c). 26 There has been some uncertainty in interpreting recent shown by the mean sizes (Table 5.11.3) there has' been LPUE trends in this fishery. It has not heen elear a reduction in size so that the 1991 length distribution whether the reduction in LPUE ohserved in 1987-89 was fell between those of 1985-86 and 1987-88, being due to a reduction in stock abundance, or due to a reasonably elose to the mean length distribution change in discarding practice as the ratio of whole to (1985-88) used in the length cohort analysis in 1990. tails in the landings increased to about 50:50. This ratio has remained at this level now for same five years and There was no reason to change the input parameters to the increase in LPUE observed in 1990 and 1991 is the 1990 length cohort analysis. The 1991 length compo probably the result of an increase in stock abundance sition was somewhat doubtful, and in any case would and/or availability. make little difference to the overall length composition. For these reasons a new length-based assessment was not Sampling of discards at sea was tried in 1991 by board carried out, and the 1990 length cohort analysis ing vessels at sea. A fishermens' discard ogive was (Anon, 1990a) remains unchanged. calculated by pooling the 8 sampies collected, which gave a mean selection length of 28 nun (Carapace Age Based Assessment Length), and a selection range of 5 nun. If it proves possible to continue collecting this data, this will in The time series oE length compositions oE the landings is future years help in the interpretation of the LPUE data short with gaps, and is therefore considered to be series. inadequate for an annual age based assessment. Mean Size Cateh Options Sampling of the landings resumed in 1991 with a total of There was no new LCA, and a VPA was not possible. • 13 sampies, though they were not weil stratified thraugh Last year's Y/R from the LCA suggested that fishing out the fishing season. The mean sizes of 32.1 nun and effort should not be allowed to increase. The landings on 33.4 mm for males and females respectively were similar effort plot (Figure 5.11.2, Table 5.1.5) has been updated to those collected in the first two years 1985,1986) ofthe and using the average effort over the period 1985-91 series (Table 5.11.3), when mainly tails were being (18720 hours) the predicted landings, raised to the landed. There was an increase in the mean sizes in 1987 international landings, is 643 tonnes. This is some 8% and 1988 which seemed to be associated with the above last years landings option of 593 tonnes, and increased landings of whole Nephrops, and a possible reflects the increase in landings (and effort and LPUE) change in discard practice. which took place in 1991. The mean landings 1985-91 is 582 tonnes. Assessments It was noted last year that if there was a change in Sampling Levels discard practice increasing LPUE, the landings option could result in a considerable reduction in effort with Following two years without length sampies a total of 13 minimal benefit to the stock. Landings in 1991 increased sampies of landings and 8 of discards were made. Most to be 41 %above the reconunended landings option, with of the sampies were collected in July and August. The both effort and LPUE rising, but the TAC and quota seasonal stratification was thus poor. management, based as it is on ICES Area VII as a whole, had little impact on the Eastern Irish Sea (see • Input parameters Section 5.1.1 for reconunendations related to this) There were no new observations on the input parameters 5.11.2 Irish Sca West (Functional Unit 15) for this stock, they remain as in Table 5.1.3. Landings. Effort, LPUE/CPUE Length-based Assessment UK (Northem IreJand) Owing to the lack oE sampies oE the landings in 1989 and 1990 there has been no change in recent years to the The Northem Ireland Nephrops fishery has been estab length cohort assessment, originally reported in the 1990 lished since the mid 1950's when annual landings were Working Group Report (Anon, 1990a), and summarised less than 500 tonnes (Figure 5.11.3). Annual landings last year (Anon, 199Ia). rose to over 4000 tonnes by the early eighties and exceeded 5000 tonnes over the period 1986-1990. Total There is some doubt whether the 1991 sampling was Nephrops landirigs by UK vessels from Functional Unit sufficiently weH stratified to be used. The annual length 15 into Northem Ireland during 1991 was 6024 tonnes composition was compared with those of 1985-88, and as (Table 5.11.4) and is slightly higher than the 1989 figure 27 (5535 tonnes). Northem Ireland landings (5926.3 tonnes) Assessme-nt represented 62.6 % ofthe totallandings and 98.4 % ofthe UK landings from this Functional Unit. The market Sampling levels (UK (Northem Ireland) driven trend towards the landing of detached tails from small Nephrops and larger animals whole continued in Because around 80% of Northem Ireland Nephrops 1991, with 76.4% of landings as tails and 23.6% as landings are landed as tails for the 'scampi' market, the whole animals. carapace length distribution of these landings are obtained by sampling the discarded heads or Landings and catches per unit effort for the Northem cephalothorax at sea aboard commercial vessels. Approx Ireland fleet calculated from live weight and hours imately 50 kg of total catch and discards are taken from fishing (kg/hr) are shown in Tahle 5.11.5. These data are each hauI sampled and a sub- sampie of 200-300 Neph for Northem Ireland vessels with positive Nephrops rops removed for carapace length measurement. Between landings using a single net (Iess than 1% of Northem 4 to 6 voyages have been sampled per month since 1981. Ireland vesscls use multi-rigged gears). Peaks in LPUE In addition to sampling commercial catches and discards and CPUE occurred in 1982 and 1986 with a downward at sea, Nephrops landed whole are monitored throughout trend hctween 1986 and 1990. These data are discussed the year by removing sampIes of 100-200 individuals further in Section 6.2. No effort or LPUE data for 1991 from commercial landings. were availahle at the time of the meeting. Sampling levels (Republic of Ireland) Republic of Ireland Sampling levels ranged from 4-10 per month during the Revision of the 1989 ami 1990 statistics ami the prelimi peak fishery period in June-August to 1-2 during the off nary data for 1991 show that landings have risen from season. SampIes consisted of components representing 2,458 tonnes in 1989 to 2709 tonnes in 1990 and to 3366 unsorted catch, large landed whole Nephrops, small • tonnes in 1991 (Table 5.11.4). While there are no effort landed Nephrops, discarded heads oftailed Nephrops and data, it is believed that effort may have risen somewhat small whole discards. From these, length frequency in 199 I, with less boats leaving the area to fish on the distributions were obtained for males and immature, Aran grounds. The decline in the proportion discarded mature, maturing and egg-bearing females. appears to be temporarily arrested as follows:- Input parameters Year: 19841985198619871988198919901991 % discardcd (\\t): 43 40 34 29 24 24 16 20 The data used were numbers ofNephrops landed, caught and discarded in sampIes taken by Ireland and Northem Me-an size-s Ireland. These data were raised to total numbers using the landed tonnage (Briggs,1985). UK Northem Ireland Input for K and L for males and juvenile females were Although the mean size of Nephrops in catches is taken from growth data obtained by fitting normal curves relatively stahle (Table 5.11.6) landings show a down to polymodallength frequency distributions (Tully, Billis ward trend in the mean size. This is primarily due to a & McMullan, 1989). Growth data for mature female reduction in discarding as the industry take advantage of Nephrops were from tagging results (Hillis, 1979, 1987). the recent reduction in minimum landing size (25 mm to Female maturity was taken to occur at 24 mm knife 20 mm Carapace length). edged (Briggs,1988). Length-weight relationships were • those of Pope and Thomas (1955). These parameters Republic of Ireland were the same as those used in the assessments per formed at the 1990 and 1991 Working Group meetings. Changes in mean weights in catch, landings and discards Natural mortality for males was set at M = 0.3 for from 1984 are given in Table 5.11.7. These show that males. For females natural mortality of M = 0.3 was the decrease in mean weights in catches which started in used for immature animals (under 24 mm carapace 1988 continued, with mean weight in 1991 at 10.8 g, the length) and M = 0.2 for mature Nephrops. Input lowest recorded apart from 1985. Mean weights in parameters are summarised in Table 5.1.3. landings have declined from 16.2 g in 1984 to 12.3 gin 1991. There is very !ittle evidence ofa trend in discards, Length based assessment with the 1991 value of 7.3 g essentially the same as that in 1990 (7.2 g). The length based assessment performed at the 1991 meeting used landed and discarded Nephrops size composition data from the Northem Ireland and Ireland fleets averaged over the years 1987-90. This period was 28 selected because it represents aperiod of relative 'steady and SSB (Table 5.11.17) are relatively stable (around state' since the most recent increase in mesh size to 70 11,500 tonnes and 6,000 tonnes respectively) although mm in 1986. there is something of a downward trend since 1986. Ignoring the most recent year (whieh is very unreliable) The only new data available at the 1992 meeting were recruitment appears to be stable. the 1991 Nephrops size composition data for Northem Ireland and Ireland. When these data were combined Catch Options with those used at the 1991 meeting to give an average size composition over the period 1987-911illle change in Because the addition of 1991 length data made liule the previously used distribution (1987-90) was seen so difference to the data used in the 1991 LCA it was the assessment was not repeated. decided that the results from the 1991 assessment (Anon.1991a) were still valid and represented the current Age based assessment situation. These results gave a relatively flat topped yield per recruit curve and suggested that the current level of Using the new software available (Section 4.3), Northem F was about 20% beyond Fmax for males and 10-20 % Ireland and Republic of Ireland catch size composition beyond Fmax for females. It was concluded that although data (Iandings + 90% of discards) were sliced into efrort should be stabilised the shape of the yield per nominal ages. These data covering the period 1984-91 . recruit curve suggested that reduction in fishing effort to represent the total estimated Nephrops removals from the Fmax would produce only small long term gains. stock by the fishery, assuming a diseard mortality of 90 %. A multi-fleet assessment was performed on male A plot of landings against effort (Figure 5.11.5, Table and female Nephrops separately using the Laurec/Shep 5.1.5) could not be used for a catch prediction due to • herd tuning method. evidence of a time trend, as stated in the 1991 Report. Males: Although the results from the age-based analysis did not confliet strongly with those from the 1991 LCA it was There were 10 'nominal age' groups with a plus group eonsidered that further exploration of their application to at 11+. Tables 5.11.8 and 5.11.9 show the catch Nephrops assessments was required before they could be numbers and the mean weight of male Nephrops at each used for predictive purposes. In view of this decision it nominal age. Tuning options are given in Table 5.1.4, was agreed to base a catch option on the average land tuning made use of Northem Ireland effort data and ings over the reference period used in the LCA historieal F (there were no Republic of Ireland effort (1987-91) this amounted to 8,663 tonnes (slightlyhigher data). Variances in F were small compared with tuned F. than the 1991 option). Tables 5.11.10 and 5.11.11 gives F-at-age and number at age respectively. F ranged between 0.2 at age 1 to 0.6 Other Management Considerations for the middle ages (3-5) for recent years. These values are similar in magnitude to those generated by the LCA Although the cateh option for Functional Unit 15 pro performed by the 1991 meeting. Mean F(3-8) (Table posed by the 1990 meeting was overshot by the high 5.11.12) does not appear to exhibit a trend and has a landings in 1991, the TAC of the larger management poor correlation (r = -0.35) with fishing errort (Figure area (VII) in whieh this Unit is contained was not taken 5.11.4). Stock biomass (Table 5.11.12) is relatively (see Section 5.1 for further discussion of the ineffective stable (18,000 tonnes). There is lillie evidence of ness of large TAC areas). • fluctuation in recruitment. 5.11.3 Swnmary of Management Area VIIa (e:' There were 11 'nominal age' groups and a plus group at Summaries of the recent landings from this Management 12+. Tables 5.11.13 and 5.11.14 shows the catch Area are given by Functional Unit and Country in Tables numbers and the mean weight of female Nephrops at 5.11.18 and 5.11.19. By combining the recommended each nominal age. Tuning inputs are given in Table cateh option for FU14 ie 643 tonnes with that of FU15 5.1.4. Tables 5.11.15 and 5.11.16 give F-at-age and ie 8663 tonnes and allowing for the small quantities from number at age. For the most recent years F ranged from other rectangles, an overall cateh option of 9306 tonnes 0.2 at age 1 and the older age groups (9-12), to 0.8 for is obtained. the middle ages (3-6). These values are similar in magnitude to those generated by the LCA performed at 5.12 Management Area VIId,e (Area K) the 1991 meeting. Mean F(3-8) (Table 5.1L17) suggests an increasing trend with a significant correlation (r = Functional Units - None O.72,P< 0.05) with effort (Figure 5.11.4). Stock biomass 29 5.12.1 Summary or l\lanagement Arca VIId,c (Arca weather conditions in the area (most French vessels ...., operating in the area are fairly smalI, with an overall length between 20 and 25 m), rather than to over Zero TAC to prevent misreporting. exploitation of the stock. 5.13 l\Ianagement Area VIIh,cJ,k (Arca L) Republic of Ireland Functional Units - Porcupine Bank (16) lrish landings mainly at Rossaveel, were at 171 tonnes Aran Islands (17) virtually unchanged from 1990 and about 50% of their NW and W Ireland (18) 1989 level. Prior to 1989, the Porcupine Bank and Aran SW Ireland (19) Grounds were not differentiated in the landings statistics. In this relatively distant water fishery conducted mainly 5.13.1 Porcupine ßank by rather small boats, 91 % of the landings were made during June-July, the time of year when the weather is Landings, effort, CPUE and LPVE most reliable. There are no data on effort. Spain UK Landings by Spanish vessels from Porcupine Bank during Records by English vessels landing in UK and in Spain 1991 were 1021 tonnes, the lowest for the historical from Porcupine Bank are given in Table 5.13.1. The series (Table 5.13.1). This represents a decrease by 30 fishing effort dropped in 1989-90, because of the legal % compared to the 1986-1990 average landings. After questions affecting joint ventures. Landings increased in declining in 1986, landings show a gradual decreasing 1991. trend from 1987 to 1991. • Mean size Total trawl fishing effort and the CPVE in 1991 of the two components of the Spanish fleet dropped below the There were no mean size data from the Republic of level of previous years (Table 5.13.2). Since 1989 Ireland, France or UK. fishing effort has shO\\TI a decreasing trend. Spain The CPUE of trawls directed to Nephrops decreased since 1982, being in 1991 a third of the average for the The mean size of males fluctuated without trend over the 1982-1985 period, in \vhich the highest values were period 1982-1991 (values ranged between 38.7 nun and reported. The CPVE of the trawlers directed to hake, 41.0 mm Carapace length) (Table 5.13.4). Tbe mean that take Nephrops as a bycatch, declined in 1986, but size of females was fairly stable (around an average of has remained fairly steady in the period 1986-1990. The 34.3 nun) during the period 1981-1987. An increase to 1991 value is the lowest for the reference period. The 38.4 nun CL in 1988 was followed by a slight decrease CPVE of total trawl fleet showed a similar pattern. A in 1989. Tbe mean size in 1991 was comparable to the longer time series of landings, effort and CPUE data is average of the reference period cited. given in Figure 5.13.1. Assessments France Sampling level • The exploitation of the Nephrops stock in the Porcupine Bank area by French vessels started only recently viz. Length composition data of the landings in 1991 are 1981-1982. This fishery is clearly seasonal, with most collected on a monthly basis at La Coruna port by a fishing taking place during the summer months. For routine sampling programme. Since 1980, sampling level three consecutive years (1984-86) it yielded fairly large averaged 2 sampies per month of about 300 individuals catches around 1000 tonnes a year (Table 5.13.1). For per sampIe. Nephrops landings in the port of Vigo were unknov.n reasons, however, the LPUE suddenly dropped sampled monthly in 1991 but because the catches are in 1987 (Table 5.13.3). The fishery became less and less allocated in "other rectangles" or Subarea VII, this data attractive to French vessels and total effort steatlily set is not taken into account. lrish sampling took place decreasetl until in 1990, fishing effort fell to only 238 during June and July. days. In 1991 however there was a marked increase in effort although LPUE shows no sign of a similar rise Input parameters (reference port Saint Gu~nol~) (Table 5.13.3). The progressive decline of this fishery is prohahly rdated to The input parameters were the same as those assumed in the decrease in catchability of Nephrops and to the bad previous years (Table 5.1.3). Fleets of four countries 30 (Spain, France Uk ami Irelaml) are involved in the Nephrops trawl and effort but sinee these data aecount Nephrops fishery of Porcupine Bank but a long series of for only about 15 % of the landings this relationship was length composition data are available only for Spain not used for predietion. Relationships between landings (1980-91). Length composition data of Spanish landings and effort from Spanish finfish trawl (Table 5.1.5 and were applied to the French landings (1981-90) and Uk Figure 5.13.4) and between landings from finfish trawl landings (1984-91). The 1991length composition ofIrish and total international landings over the period landings were applied to the 1989-90 landings of that 1982-1991 were used in the same way as the previous country. year as a means of predicting eatch options. Length Cohort Analysis Landings finfish trawl = 39.9 * effort - 2478 (r=0.919) A comparison of 1991 length composition data showed Total International landings = no difference with the average of 1981·90 period and the 1.472 * landings finfish trawl + 754 (r=0.914) LCA was not repeated. The YIR curves resulting from the 1991 LCA for both sexes indicated that current F Taking into aeeount the mean effort over the last five was above Fmax and that Fmax would be reacheJ with years as a means of stabilising effort the above deereases in the fishing effort of50 % for males and 30% regressions predict a total international landing of 2400 for females. The lang term gains in yield with this tonnes. Although the new value represents a 4.5 % reduction in fishing effort are relatively small (below reduction eompared to the value obtained in 1991 (2514 10%). tannes), it is similar to the mean + sd ofthe 1987-1991 values and is eonsistent with the deereasing trend in Aged based assessment landings and fishing effort sinee 1989. • Males: 5.13.2 Aran Grounels (Galway Bay) (Functional Unit 17) Catch at age was estimated for males by slicing length compositions of males for the period 1981-90. 10 Landings. effort. mean size 'nominal ages' (11 plus group) were considered. 'Age' compositions were generatcd for each fleet and a tuning Landings were reported by freiand, and Franee (Table file created. Tables 5.13.5 and 5.13.6 give combined 5.13.10). lrish information separating Aran data from catch at age and mean weight at age. The fishing effort Poreupine Bank data, available from 1989 showed Aran index from Spanish vessels was used for tuning. The eatches to greatly exceed those from the Porcupine input choices are given in Table 5.1.4. The catchability grounds. However, the only lrish information prior to coefficient was fixed for this fleet, other fleets were 1989 relates to the sum of Poreupine and Aran catches excluded, as was historie F. Variance in F was small whieh rose from a very low level to 1,665 tonnes in eompared to tuned input F. Tables 5.13.7 and 5.13.8 1985, sinee when it has fluetuated do\',nwards to 691 give F at age and numbers at age. Fbar, total stock tonnes in 1988. The Aran grounds are generally fished biomass, spawning stock biomass and log reeruitment when conditions are unsuitable for the Poreupine, hence were estimated for a range of 3-8 'nominal ages' (Table they are not much fished in June or July. In 1991, nearly 5.13.9). The Fbar vs fishing effort Figure does not show half the cateh was taken in May, and very little during any signifieant eorrelation eoeffieient (Figure 5.13.2) so September and Oetober. Landings in 1991 totalled 550 it is more difficult to interpret the results. The difficulties tannes (of which 520 tonnes were Irish). Effort data are • eould be because the method has been applied in a not available for this fishery and there is no time series multifleet case where there were inadequate data. from whieh to assess ehanges in mean size. Mean weight in 1991 for landings was 21.9 g (males 26.2 g, females Females: 15.5 g); some diseard sampIes were also obtained and found to eonstitute about 6 % of the catch, a slightly Teehnical difficulties in generating female length compo higher pereentage than had previously been supposed. sitions precluded them from similar analysis. Assessments Catch options Sampling Owing to the ralher unsalisfactory results of the VPA, last years LCA results were taken as a guide to the stale Length frequeney distributions from sampies were raised of the stock. These suggested that, at least, effort should to give an estimate of the total numbers caught. Some be stabilised. sampleJ catches were landeJ sorted into more than one size category; sampIes were therefore raised first to total Figure 5.13.3 shows the relationship between landings of boat landings level (to obtain eorreet proportions in each 31 category) amI the total thus obtained sununed and raised 5.13.3 Republic of Ireland Coast (NW, Wand SW) to port level. Tails were sampled by measuring breadth (Functional Units 18 and 19) of the 5th abdominal segment in 0.5 nun categories and converting values to carapace length using a factor of Landings 2.0. The 5th segment of the abdomen is seldom broken during tailing, unlike more anterior parts and the conver Table 5.13.13 gives landings figures for these two sion factor is an approximation to 2.03 for males and functional units. There were no effort data, no mean size 1.97 for females. Carapace lengths for males ranged data and insufficient data to carry out a length based from 16 to 55 mm amI those of females from 16 to 43 assessment. nun. Modal numbers of males occurred at 31 mm and those of females at 29 mm. Catch option Input Parameters Catch options based on the maximum landings are probably the most appropriate. These are 90 tonnes for Growth parameters for males and immature females were FUIS and 725 tonnes for FUI9. L.. = 60 mm, (equal to the west Irish Sea), K = 0.15 (intermediate between the Irish Sea and the currently 5.13.4 Swnmary of Management Area VIIb,cJ,k used values for Porcupine Bank assessments) and M = (Aren L) 0.3. For mature females the values used were L.. = 50 mm, K = 0.10 and M = 0.2. Full details of inputs are Sununaries of the recent landings from this Management given in Table 5.1.3. Area are given by Functional Unit and country in Tables 5.13.14 and 5.13.15. The following text table Length-based assessment summarises the catch options proposed for this Manage ment Area. For FUs 18 and 19 and for the "other" • The assessment is based on the reference period 1990 statistical rectangles, the maximum landings in the period and 1991. 1982-91 have been adopted to give overall catch options. Results FU Derivation of option Total Output results from the LCA are given in Tables 5.13.11 landings and 5.13.12. Since it must be emphasised that the input (t) data used in this assessment are somewhat weak (based on only two years' length frequency uata) and since 16 Av. effort 1987-91 2400 reliable growth parameters are not yet available, the 17 Av. landings 1989-91 575 assessment must be viewed with caution. Both sexes appear to be about optimally fished, Fmax occurring at 18 maximum landings 90 20% above current F for males and 10% below for 19 maximum landings 725 females. Long term gains in yield however, are negli gible, being less than 0.5 % above current yield levels for Other maximum landings 266 both sexes (Figure 5.13.5). Total 4056 Catch option • Bearing in mind that with a 550 tonne catch in 1991, this is overall a small fishery, and it would only require the 5.14 Management Aren VIIf,g,h and Vlla: rcc entry of a few boats to increase effort by a considerable tangles 33E2·E5 (Aren 1\1) proportion. It is suggested that until more reliable data are available, effort shoulu not be allowed to increase Functional Units - Celtic Sea (20-22) markeuly. In audition, the uncertainty about lanuings prior to 1989 means that a catch option based on recent 5.14.1 Celtic Sen (Functional units 20+21+22) landings figures is most appropriate. An option based on a three year average of recent lanuings gives 575 Landings. efemt and LPUE tonnes.This is e10se to the lanuings for 1991, at 550 tonnes. Landings were reported by France, Ireland, UK and Belgium. In recent years French landings have accounted for over 85 % of the total. 32 ..' . The Freneh Nephrops rishery in the Cdtie Sea is pros were obtained from a number of cOnUnercial vessels; ecuted by vessels landing their catehes in the Southem discard sampling cannat be performed every year owing part of Brittany. Over the last 10 years, landings have to financial constraints and the last sampling programme fluetuated around 3000 tonnes/year, with peaks of over was in 1985. 3500 tonnes in a number ofyears, viz in 1983,1984,1985 and 1990 (3762 tannes) (Table 5.14.1) In 1991 they Input parameters dropped to 2652 tannes. Discanling is substantial in this fishery. The commercial minimum landing size being The biological parameters which were used are given in cIearly above the legal minimum landing size set by the Table 5.1.3 and remain unchanged from last year. EEC (35 mm CL as opposed to 25 mm CL). At 412 tannes Irish landings, though weIl below their 1989 peak Length based assessment of 784 tonnes, were still abmte their 10 year mean of about 380 tannes. As no new parameters were available, and addition of data for 1991 did not change the average length distribu Fishing effort (referenee port Saint GuenoM) has steadily tion (seen by plotting average frequencies at length for increased over the past years from about 4100 days 1987-90 and 1987-91) it was considered not necessary 10 fishing in 1985 to almost 5460 days in 1990 (updated repeat the length based assessment earried out last year. figure) (Table 5.14.2). The effort figure for 1991 is The 1991 length based assessment, with a reference highly provisional and does not include data for Novem period from 1987-1990, gave a Y/R curve with F max at ber and December 1991. Effort in 1991 is likely to be 40 % below current F for males and Fmax far above below the 1990 value because a number of vessels current F for females. switched to fishing tuna fish in the summer of 1991. • LPUE values which were fluctuating around 250kg/day Age based assessment until 1990 suddenly dropped to 181 kg/day in 1991 which remains difficult to explain. As there are French and lrish vessels involved in the fishery, it was decided to perform a multi-fleet assess French total effart data were available this year from ment. The only lrish data available were landings until 1984 to 1990 (Table 5.14.2). Since the EEC log-baak is 1990 (1991 landings were provided too late in the compulsory for a11 vessels which fish in this area, effort meeting). French length distributionswere available from records are expected to be better than in the Bay of 1984 to 1991, but since French total effart data were not Biscay. Total effort decreased from 247637 hours in available for 1991, nor were lrish landings for that year, 1984 to 183203 haurs in 1988 and then increased to the age based assessment anly took into account 1984 to 210374 haurs and 282290 haurs (maximum value of the 1990. series) in 1989 and 1990. LPUE in Kg/hr has apparently fluctuated without obvious trend. The trends in landings, French distributions of dead discards and landings were effart and LPUE are shown in Figure 5.14.1. There applied to Irish landings in order to derive lrish length were no lrish effort data. distributions. This probably gave overestimates of discards for Ireland, since the minimum landing size is Mean size set at 35 mm in France for commercial reasons. Length compositians from French sampling (see be1ow) Males: • provided information on the mean size. The mean sizes of males and females landed remained fairly stable over The length distributions were split into 7 'nominal age' the period 1984-91 (38-39 mm for the males and 35-36 groups (plus-group at 8). Catch and weight at age are mm for the fe males) (Table 5.14.3). No mesh change given in Table 5.14.4 and 5.14.5 respectively. Inputs occurred over this period. chosen for the tuning procedure are given in Table 5.1.4. As no effort data were available for the lrish fleet it was Assessments excluded from the tuning. Variances of F obtained from effort data were lower than those of 'historical F' for a11 Sampling ages, and received more weight in the ca1culation of tuned F. Variances about F were much lower than tuned Length camposition data of the landings are collected F. F at age and number at age are given in Tables 5.14.6 throughout the year in the three main home ports of and 5.14.7. The 10west values of Fbar (Table 5.14.8) are Celtic Sea Nephrops trawlers. The number of vessels Q.30 and 0.39, these correspond to the lowest total effort taking part in this fishery (about 100) is much srna11er values, from 1986 to 1988. For the other years, Fbar is than the ane fishing in the Bay of Biscay, which also fluctuating between 0.44 and 0.56 which are slightly explains the lower sampling levels (3-4 sampies of 50 higher than values obtained from the Length based Nephrops each per rnon\h). In 1991 sampies of discanls assessment of last year (mean F at 0.33 and maximum F 33 at 0.47). The regression of Fbar against effort gives a 5.14.2 Swnmary for 1\Iana~ement Arca VIIf,~,h and significant corrdation at a probability of less than 5% VIIa 33E2-E5 (Arca 1\1) (see Figure 5.14.2). Since the time series of 7 years is not long enough to rely on an age based VPA, it is Summaries of the recent landings from this Management premature to give conclusions about biomasses and Area are given by Functional Unit and Country in Table recruitment. 5.14.14 and 5.14.15 respectively. The catch option for this area 3500 tonnes includes an allowance for the other Fernales: rectangles (see above). The length distributions were split into 9 'nominal age' 5.15 l\Iana~ement Arca VIlIa,b (Arca N) groups (plus-group at 10). Catch and weight at age are given in Tables 5.14.9 and 5.14.10 respectively. Inputs Functional Units - Bay of Biseay (23 and 24) chosen for the tuning proceuure are given in Table 5.1.4. As for the males, Irish fleet data were excluded in the 5.15.1 nay of ßiscay (FunctionaI Units 23+24) calculation of tuned F. Variances of F obtained from effort data are at least 10 times higher than for males, Lllndings. effort lind LPUE and were of comparable magnitude to the value of tuned F making the assessment less reliable. Historie F was Landings from these units were predominantly by French included. F at age and numbers at age are given in vessels and Spain reported landings from rectangles Tables 5.14.11 and 5.14.12. Fbar values (Table 5.14.13) outside the Functional Units but inside the Management are low; 0.19 in 1984 which increases to 0.34 in 1985 Area (see Tables 5.15.1 and 5.15.15). Over the past ten and decrease to 0.13 in 1988. For comparison, the length years, Neplzrops landings from this area averaged 5200 based assessment of last year gave a mean F at 0.03. tonnes, the largest catches having been taken in 1983, • The regression of Fbar against effort gives a non signifi 1987 and 1988 (Table 5.15.1). Landings have been cant correlation (see Figure 5.14.2). Since the time series decreasing since 1989. Fishing effort (reference port of 7 years is not very long amI F values are very low it LesconiI) dropped from 6709 days in 1982 to 5137 days is unwise to rdy on the age hased VPA and too prema in 1986, following aperiod ofstability in the years 1987 ture to give concIusions ahout biomasses and recruitment. to 1989 (Table 5.15.2) effort dropped to below 5000 days in 1990 and 1991. The decrease went along with a gradual change in the fishing practices of the Bay of The unreliability of age based assessments for the Celtie Biscay Nephrops trawlers, which have tended to divert sea may be due to the impossibilityofsampling separate their effort to finfish in the seasons of reduced Nephrops ly the 3 Functional Units because vessds can fish in the availability (autumn - winter). The LPUE show no 3 areas in a same trip. The variations of proportions of particular trend (Table 5.15.2), instead they have effort allocated to the 3 Units mayaIso vary from year fluctuated around 100 Kg/day throughout the reference to year. This may confound the assessment process. period (1982-91), with peak values in 1983 and 1988. The recent decline in LPUE in 1990 and 1991 is in line Catch options with the decline in effort. The conclusion of last year length based assessment was Total effort data were available this year (Table 5.15.2) that effort should not be allowed to increase, with F max at but only from 1984 to 1990. The steady increase from 40% below current F for the males. Expected landings 470991 hours in 1984 to 757141 hours in 1988 is more • were calculated using a relationship between landings and due to improvements in fishery statistic records than to raised effort, by setting the desirable effort as the mean areal increase in effort. A lot of vessels fish in coastal observed for the reference period 1987-1990. The catch areas and are not required to submit an EEC log-baok, option for 1991 was set at 3523 tannes and the observed implying that anational recording system is also desir landings were only about 3000 tonnes. As total effort able at present. Total effort has been decreasing in 1989 data are now available for 1984 to 1990, a new relation and 1990 as observed in the partial effort series, explain ship was calculated this year (Table 5.1.5, Figure ing the drop in landings. The time series of landings, 5.14.3). Note that this year the totallandings used in this effort and LPUE data are shO\vn in Figure 5.15.1. relationship ineluded those taken in 'other rectangles' (see Table 5.14.14). The average of hours fished for the Mean !'i1.e 87-90 period was put into the new relationship and gave a value of 3547 tannes. For the time heing, considering The consecutive mesh size increases, from 45 to 50 mm that the age basel! asscssmcnt requircs same progress in 1986 and again from 50 to 55 mm in 1990 have before being used to make predictions, it is suggested to resulted in an increase of the mean sire of Nephrops keep the catch option set at ahout 3500 tonnes which is landed (Table 5.15.3 ). It is difficuIt therefore to eom elose to last years option. ment on effects on mean size that fishing may have had. 34 Tbe difference in the changes in mean size between only. Tbereafter historie F made a greater eontribution males and females can be attributed to the differences in owing to its lower variance. Variances were small growth pattern between the two sexes. compared to tuned F. F at age and number at age are given in Tables 5.15.6 and 5.15.7 respectively. Fbar Assessments values for the different years do not show any particular trend (Table 5.15.8) but rather fluctuate around 0.45. Sampling levels Tbe regression of Fbar against effort (Figure 5.15.2) gives a non-significant correlation, which could be due Length frequency data are being collected throughout the to the quality of effort <.\ata as reported previously. year from sampIes of landings taken in the northern part Values of Fbar are slightly higher than the mean value of of the Bay of Biscay. These represent 70-80% of the 0.37 obtaine A discard sampling programme has been performe 35 of 5576 tonnes. As there is no strong reason to set a Assessments lower option than was suggested last year, it is proposed that the 1991 catch option of 6745 tonnes he retained. Sampling Levels 5.15.2 Summary of l\Iana~cmcnt Arca Vllla,b (Arca Landings are sampled on a monthly hasis at La Coruiia N) port. During the period 1984-1991 the sampling level averaged 38 sampIes and about 3300 individuals per Summaries of the recent landings from this Management annum. Area are given hy Functional Unit and country in Tahles 5.15.14 and 5.15.15 There were landings made hy Input Parameters France and Spain from statistical rectangles outside the Functional Units hut inside the Management Area. The Length compositions used were 1984-1991. Input growth Catch option for the Management Area is obtained, parameters and M for hoth sexes were the same as in the therefore, hy adding the maximum landings (in the 1991 LCA (Table 5.1.3) reference period) from the "other" rectangles ie 142 tonnes, to the catch option given in Section 5.15.1 ie Length Based Assessment 6745 tonnes. The overall catch option is therefore 6887 tonnes. There was no new information about the input hiological parameters so,for this reason, a new length based 5.16 l\lana~cmcnt Arca Vlllc (Arca 0) assessment was not made and the 1991 LCA remained unchanged. As was indicated in a previous report Functional Units - North Galicia (25) (Anon., 1991a) the Y/R curves indicate that eurrent F is Cantahrian Sea (31) 40 % above Fmax for hoth males and females. A reduction of current levels of effort to the Fmax predicted a small • 5.16.1 North Galicia (Functional Unit 25) gain (~ 5% for hoth sexes) in long term landings. Landings. Effort ami CPUE Age Based Assessment Landings were reported hy Spain only. There was a Landings were reported by Spain only so, a single fleet revised landings figure for FU-25. Landings from North assessment was done. Effort data (in number of trips) Galicia Nephrops fishery have fluctuated over the period was available for the 1984-1991 period. 1982-91 between 289 and 514 tonnes. Landings in 1991 were 416 tonnes, above the minimum of 289 tonnes Males: reached in 1990 (Table 5.16.1). Length eompositions were split into 9 'nominal age' Table 5.16.2 gives the fishing effort and CPUE for 1982 groups (10 = plus group) using the slicing technique - 91 (port of reference La Coruna). A decreasing trend described. Resultant catch at age and weight at age are in fishing effort occurred during the period 1982-87. shown in Tables 5.16.4 and 5.16.5 respectively. These Then, after an increase during 1988-89, effort remained were input to the VPA tuning whieh used Spanish effort steady in 1990 but dropped slightly again in 1991. data and historie F. Choiees for tuning input are given in Table 5.1.4. The tuning output gave F estimates with CPUE (there are no discards) fluctuated without trend reasonably small varianees. Tables 5.16.6 and 5.16.7 (Tahle 5.16.2). The 1991 value recovered the level of show F at age and N at age. The F bar (F 2-6) values • previous years, after the minimum of 1990. Longer time for males (Table 5.16.8) ranged from 0.88 to 0.45. After series of lamlings effort and CPUE are shown in Figure declining in 1986 they showed a gradual increase to 5.16.1 1989, dropped again in 1990 to the lowest value and increased in 1991 to 0.61. The plot of Fhar on effort Mean Si7e (Figure 5.16.2) gave a correlation for males ofr=0.629 hut this was not significant. TSB fluetuated without trend Table 5.16.3 gives the mean size of Nephrops males and (5.16.8) and recruitment fluctuated from 1984 to 1990 females in landings. Since 1986 there has been an showing a minimum in 1991 which was markedly lower increasing trend for hoth sexes continuing until 1989 for than earlier years . Bowever, estimates in the most males anu until 1990 for females. Sinee 1989 the mean recent year are unreliable. size for males shows a uownwaru trenu. The mean size for females in 1991 decreased to a level corresponding to Females: the early 1980's. Length compositions were split into 10 'nominal age' groups with a plus group at 11. The resultant eateh at 36 age amI weight at age are give~ in Tables 5.16.9 ami stable. 5.16.10. These were input to the VPA tuning which, as for the males, used Spanish effort data and historie F. Assessment Choices for tuning input are given in Table 5.1.4. The tuning output gave F estimates with reasonably small Sarnpling levels varianees compared to the magnitude of input F. Tables 5.16.11 and 5.16.12 show F at age and N at age. F bar Length composition data from monthly sampling of for females (Table 5.16.13) fluctuated from 0.31 to 0.55 landings al Avils and Santander were raised to area without trend. The plots of Fbar on effort gave a poorer landings. An average of 30 annual sampies were exam correlation for females (r=O.II) than for males (Figure ined in the 1988-1991 period, with about 220 individuals 5.16.2). TSB fluctuated without trend (Table 5.16.13) per sampie. and values were lower than for males. This is consistent with the results of the 1990 LCA but is not comparable Input parameters to other stocks assessed in this report, where the fernale biomass is generally higher than that of males. Recruit All input biological parameters remain the same as in ment fluctuated for females from 1984 to 1990 showing previous years (Table 5.1.3). a minimum in 1991 which was markedly lower than earlier years (Table 5.16.13) . However, estimates in the Length based assessment most recent year are unreliabk Because the input parameters remain unchanged and the Catch Options 1991 length composition data showed little differences wilh the average 1988- 90, the LCA carried out in 1991 Owing to uncertainty in the quality of the VPA, more was not repeated. • attention is paid to the indicators from last years LCA. The recommenued management option woulu be The Y/R results of the 1991 LCA showed that current F stabilising the fishery at the average level of fishing is 30% above Fmax for males and weil below Fmax for effort over the reference periou ofLCA with the addition fernales. A reuuction in effort towards Fmax will mean of the most recent data of 1991. Because significant small gains in long term landings for males (about 3 %) correlations are not found between landings and effort while for females it woulu give losses of about 10 %. nor between landings and LPUE in year t-l, (Table 5.1.5, Figure 5.16.3), the mean value of the landings Age Based Assessment over this periou is suggested instead (Table 5.16.1). This amounts to 411 tonnes and represents a small increase The length cornposition data senes available is too short compared to the previous value given in 1991, mainly (1988-91) for a reliable age based assessment For this due to the revision of the landings figure. reason this analysis was not carried out. 5.16.2 Cantahrian Sea (Functional Unit 31) Catch Options Landing~. effort amI CPUE The management option given in the previous report remains unchanged. The mean value in the reference Nephrops lanuings uala are available from 1983 to 1991 periou of the LCA (1988-1990) 158 tonnes, was not (Table 5.16.14). Landings uoubleu from 1983 10 1985 changed significantly by the audition of the 1991 data. • and remained around 130 tonnes between 1985-89. Landings increased in 1990 reaching a peak of 185 5.16.3 Summary of l\Ianagement Arca VlIIc (Arca tonnes but in 1991 uecreased by 40 % to 108 tonnes. 0) Effort and CPUE (there are no discards) of the trawlers Summaries of the recent landings from this Management of Avils are available for the period 1983-91 (Table Area are given by Functional Unit and country in Tables 5.16.15). CPUE show an increasing trend from 1986 to 5.16.17 and 5.16.18. The catch option for the area as a 1990. The 1991 data are somewhat below the average of whole is given by adding the catch option for FU25 ie previous period. 411 tonnes to the catch option for FU31 ie 158 tonnes. There were no landings from "other" rectangles. The Mean size overall catch option amounts to 569 tonnes. Data on mean size of males ami females for 1988-91 are 5.17 l\Ianagement Arca VlIId,e (Arca P) available (Table 5.16.16). In this short period no trenus are revealed and mean sizes of around 40 mm Carapace Functional Units - None length for males amI 37 mrn for fernales appear to be 37 5.17.1 Summary ()fl\lana~ementArea Vllld,e (Area Length based assessment P) Tbe reference period for 1991 LCA was 1989-1990. Zero TAC to prevent misreporting. When 1991 length composition data were incorporated the average length composition was little different and 5.18 l\Iana~ement Area IXa (Area Q) the LCA analysis was not repeated. Functional Units West Galicia (26) As indicated in a previous report (Anon., 1991a),the Y/R North Portugal (27) curves indicate that current F is 40 % and 50% above SW and S Portugal (lP&2J) Fmax for males and females respectively. With reductions Gulf of Cadiz (30) of effort of the same proportions, the 10ng term benefits would be about 10% for males and 15% for females. 5.18.1 West Galicia (Functional Unit 26) Age based assessment Lamlings. errnrt ami CrDE No age based assessment was made because the lack of length compositions in 1984 and 1987 which left too Landings made exclusively by Spanish vessels were short aseries of years for VPA. reported by Spain. Nephrops landings from West Galicia were 549 tonnes in 1991 recovering from the fall to 400 Catch Options tonnes in 1990 and approaching the earlier range, 600 825 tonnes, during the period 1981·1989 (Table 5.18.1). LCA results suggest that effort should at least be stabil A plot of long term landings is shown in Figure 5.18.1. ized. The management option suggested in the last report, 514 tonnes, remains since the addition of the crDE data (there are no discards) are available for the 1991 data produced only a small change (to 525 tonnes). • fleets of Muros and Rh'eira since 1984 and for the fleet Tbe option was based on the average of the landings in of Marin since 1990 (Table 5.18.2). These data show the reference period for the LCA (1989-90), because the fluctuations with low values in 1990. The figure for effort data series did not cover all fleets (only two ports Marin is high due to the fact that one trip for Marin were used) precluding the use of a landings and effort vesse1s is of three days duration by contrast to a day per relationship. trip made by the vesse1s of Muros and Riveira. Me:!n size 5.18.2 North Portugal (North or Cape Espichel) • Functional Unit 27 Tbe mean size of males and females in the catches are given in Table 5.18.3 for 1982-83, 1985-86 and 1988-91. Landings From 1981 to 1988 mean sizes of males and females have fluctuated without trend. A rather accentuated A new series of estimated catches is available for dec1ine was apparent in females between 1982-83. 1986-1990 period. The estimates were based on data However, a fall in mean size of both sexes occurreJ in collected from log-books combined with the total number 1989 and continued in 1990 (from 35.0 and 32.9 CL mm of vessels which have landed Nephrops. For 1987-89 in 1988 to 26.0 and 24.8 in 1990 for males and females period the estimated catches are lower than the official respectively). The mean size in 1991 recovered but was statistics reported in 1991 Working Group Report. Prior below the average of 1982-90 period. to 1986 the catches were revised but no important • changes occurred when compared with the data previous Assessment Iy published in the Working Group. Sampling level Table 5.18.4 ami Figure 5.18.2 show the evolution of totallandings during 1980-1991 and by gear (trawl and Landings were sampled at Marin and Vigo ports on a creel) since 1985. Total landings from this unit have monthly basis. During the period 1989-1991 the sampling fluctuated between 14 and 96 tonnes per year. Tbe level averaged 33 sampies and ahout 7800 individuals per maximum landing of 96 tonnes was reached in 1988 and annum. the lowest in 1982 and 1984 (14 tonnes per year). Catches increased from 1986, stabilising in the last two Input parameters years at about 50 tonnes per year (70 % caught by trawling). Discarding does not take place in the Portu The input parameters remained the same as in previous guese fishery of this Functional Unit. years (Tahle 5.1.3). 38 Effart llnd epUE . make some efforts to obtain logistic support to sampIe those catches in the Spanish harbours. Fishing effort ami CPVE for trawl fishery were esti mateJ for 1985-1991 period on the basis of log-books No sampling of creel lanJings took place. Length and shipo\\ners association data. Table 5.18.5 and Figure frequency distributions of the catches of creel were 5.18.2 show the changes in fishing effort and CPVE. estimated assuming they follow the same pattern as the Fishing effort is expressed both in number of trawlers length frequency distributions from the trawl landings. and fishing hours and CPVE is presented in tonnes per Length frequency distributions for 1985-1990 were trawler and Kglhr. Fishing effort in terms of fishing reviseJ according to the new estimates of the catches on hours increaseJ markedly Juring 1985-1987, from 5.4 to that perioJ. Length frequency distributions for 1987 was 14.2 thousaml of fishing hours. During 1988-1991 assumeJ to bave tbe same pattern as the one estimateJ fishing effort decreaseJ to a level corresponding to half for 1988. As a small number of sampies were laken of the 1987 level. Since 1987, the total number of during 1991 including only small individuals it was trawlers catching Neplzrops has been kept stable (around considereJ not advisable to use 1991 data. 8 per year). CPUE has fluctuateJ during 1985-1991. The estimates show a decrease during 1990-1991 (Table Input parameters 5.18.5). No input biological parameters are available for this Mean si7.e Functional Unit. It was JeciJeJ, as in the previous meeting, to use the parameters estimateJ for FUs 28+29 Mean carapace length data, for males and females, from (SWand South of Portugal). The input parameters are trawl landings and from research survey catches are given in Table 5.1.3. For females two growth curves available for 1985-1991 (no survey took place in 1989) were aJopteJ with a transition length at 26 mm carapace • amI is presented in Table 5.18.6. Ouring 1987 no length. sampling took piace in the fishing harbours and during 1991 only 3 sampIes were measureJ. The results inJicate Length baseJ assessment that the mean campace length from the landings is higher in this Functional Unit than in the Southem Functional As no new information about growth parameters was Units ofthe Portuguese coast (Units 28 and 29). Further presenteJ there was no neeJ to repeat the length cohort more it shows that mean size has decreased since 1989. analysis performed in 1991 Working Group Report. Although length frequency distributions have been Mean size from survey catches inJicate fluctuations reviseJ they bave kept tbe same proportional distribution which may be due to different codend mesh sizes used in pattern and tberefore the results do not change. different surveys, therefore the mean sizes cannot be compareJ. For 1991 the mean sizes were proviJeJ from The preliminary results provideJ from LCA performeJ one grounJfish survey carried out in Auturnn with a 20 at 1991 Working Group indicate that current level of F mm codend mesh size. The mean sizes estimated in 1991 for males is 20 % beyond the level of Fmalt and for are smaller than those obtained in previous years. females the current level of fishing mortality is far below the level of Fmalt' For males a reJuction in effort from Assessments the current level to Fmalt would increase the long-term landings by 2 %. In females increases in effort by as Sampling level much as 50 % would increase the long-term yield by • only 7 % and would decrease long-term biomass by 26 Length composition da ta concems trawl catches and are %. ReJuctions in effort would increase long term baseJ on a small number of sampies which did not cover biomass of both males and females. all months (except 1988). Ouring 1985-1990 the average number ofsampies taken annually was 21 (36 inJividuals AgeJ based assessment per sampIe for each sex), except during 1987 (no sampling took pIace) and during 1991 when only 3 Catch at age was estimateJ converting annual length sampies were measured. distributions into 'nominal age' distributions using the slicing technique on annuallength frequency distributions Ouring 1991 the 3 sampIes had corresponded to a total by sex for the period 1985-1990. of 100 measured individuals, ranging from 24 to 44 mm length carapace ( both males and males). This length Males: range is smaller than in the previous years and it is due to the fact that medium and large Nephrops are landed in From the splitting, 'nominal ages' range from 1 to 6 (7 the Spanish fishing harbours of Vigo and Marin where plus group). Tables 5.18.7 and 5.18.8 show catch at age the price is higher. The Portuguese Institute is starting to and mean weight at age which were useJ as input to the 39 • VPA. Catch options Terminal fishing mortality was tuned using fishing effort Since the VPA results are at present questionable, the data, historie F was excluded. Table 5.1.4 shows the LCA of last year is taken as a guide. This suggested that tuning input choices. The variances about the F values effort should be stabilised. At the 1991 Working Group were large compared to the tuned F values. Tables the catch option estimated was based on the average 5.18.9 and 5.18.10 present the F at age matrix and 1980-1985 landings figures due to the fact that for population in numbers (thousands) at age respectively. 1986-1990 the official landings figures were not con sidered reliable. A precautionary TAC of 40 tonnes was The average fishing mortality for ages 2-6 , as weIl as then recommended for 1991. During 1991 a higher Total Stock Biomass (TSB), Spa\\ning Stock biomass (estimated) catch of 54 tonnes was laken. (SSB) and log Recruitment are presented in Table 5.18.11. The plot of Fbar versus fishing effort, is Since catches have been revised for the whole period and presented in Figure 5.18.3. The relationship is not are now considered more reliable a catch option based on statistically significant Fishing mortality (Fbar) has a recent period, the average 1987-1991 estimated fluctuated for males from 0.09 in 1986, which is some catches, may now be proposed this amounts to about 70 what lower than natural mortality (M=0.2), to a value of tonnes. A plot of landings versus effort is sho\\TI in Fbar =0.63 in 1989. In 1990 Fbar for males is elose to Figure 5.18.4. This was unfortunately not significant 0.30. (Table 5.1.5) but could be more useful when additional data are available. The results may give imlications that this Functional Unit is not being exploited in stable situations during 5.18.3 South West and South Portu~al (Functional 1985-1990 period, which is consistent with the decreas Units 28 and 29) ing trends in fishing effort since 1987. The VPA results • must be interpreted with caution since growth parameters Landings used are the same as those estimated for FU 28+29. A new series of estimated catches is available for the Females: 1986-1990 period. Catches were estimated from data collected from log-books combined with the total number From the splitting, 'nominal ages' range from 1 to 9 (10 of vessels which have landed Nephrops. For 1986-90 plus group). Tables 5.18.12 and 5.18.13 show catch at period the estimated catches are lower than the official age amI mean weight at age which were used as input to statistics reported in 1991 Working Group Report with the VPA. the exception of the year 1989. The portuguese catches made prior to 1986 were also revised resulting in slightly Terminal fishing mortality was tuned using fishing effort higher catches than those published in the 1991 Working data, historie F was excluded. Table 5.1.4 shows the Group. tuning input choices. The variances were very large compared to tuned F. Tables 5.18.14 and 5.18.15 Table 5.18.17 and Figure 5.18.5a show recent total present the F at age matrix and population in numbers landings by gear (trawl and creel) since 1987. Total (thousands) at age respectively. Fishing mortality rates landings from this unit have fluctuated between 257 and are extremely low. 1607 tonnes per year. The maximum landing of 1607 tonnes was reached in 1980, when the Spanish trawl fleet The average fishing mortality (Fbar) for ages 3-8 , as was fishing in Portuguese waters, and the lowest catch • weil as Total Stock Biomass (TSB), Spa\\ning Stock was recorded in 1983 which correspond to the first year biomass (SSB) and log Recruitment are presented in when only the Portuguese fleet was operating. Table 5.18.16. The plot of Fbar versus fishing effort, is presented in Figure 5.18.3. The re1ationship is not Since 1983 the estimated catches have increased from statistically significant although slightly better than for 257 tonnes to around 500 tonnes in 1987. Since then the the males. For females Fbar varied from a lowest value catches have fluctuated around an average level of 430 of .0015 in 1985 to a maximum value of 0.01 in tonnes per year. For 1991 the estimated catch was 1988/89. For 1990 Fbar estimated of 0.0061 is smaller around 480 tonnes which is 30 % higher than during than the value estimated for 1989. 1990 (370 tonnes) (98 % was caught by trawling). Discarding does not take piace in the Portuguese fishery The VPA results must be interpreted with caution since of this Functional Unit. growth parameters used are the same as those estimated for FU 28+29 and because the values of F are very Effort. CPUE and LPUE mueh lower than the natural mortality rate. Fishing effort and CPUE for the trawl fishery were 40 • estimated for 1982-1991 period on the basis oflog-books Length frequency distributions for 1984-1990 were and shipoy,ners association data. Table 5.18.18 ami revised aceording to the new estimates of the catehes for Figure 5.18.5 (b ami c) show the fishing effort amI that period. It should be noted that at the last Working CPUE. Fishing effort is expressed both in number of Group, length frequency distributions were treated in trawlers and fishing hours and CPUE is presented in terms of percentages due to the fact that landings statis tonnes per trawler and Kg/hr. tics were not reliable for 1986-1990. At present length distributions are revised and they eorrespond to an Fishing effort in terms of fishing hours showed a big improvement in catch estimates as mentioned above. increase between 1982-1985; from 1985 to 1989 it decreased reaehing a minimum in 1989 with 52.0 Input parameters thousand hours. During the two most recent years there has been a slight inerease of about 20 % when compared Tbe input biological parameters were the same as those with 1989. Total number of trawlers whieh caught estimated in the 1990 Working Group (Table 5.1.3). For Nephrops inereased from 14 units in 1982 to 41 in females two growth curves were considered, setting the 1986/1987. Since then the number of trawlers catching transition length at 26 mm carapace length. Nephrops has been kept stahle (around 37 per year). Length based assessment Cateh per unit effort inereased from 1982 to 1984 both in terms of tonnes per trawler and in kg/hr. Sinee 1984 Length frequency distributions for 1984-1990 were cpue has Ouetuated around an average value of 12 revised. due to revisions on catehes estimates, however tonnes/trawler and 6.3 Kg/hour. those changes do not produce any changes in the dis tribution pattern. As no new data on growth parameters Mean size was presented it was not eonsidered necessary to perform • a new length cohort analysis. Mean carapace length data. for males and females. from trawl landings and from research surveys catehes are Results derived from LCA carried out during 1991 available for 1983-1991 amI are presented in Table Working Group indicated that for males the current level 5.18.19 The mean size of Nep!lrops in the landings for of F is 50 % above the level of F max and for females both sexes has inereased between 1987 and 1990. In current F is 30-40 % above Fmax' In males a reduction in 1991 a decrease was recorded for both sexes whieh may eurrent F to Fmax level would improve long-term landings be due to the fact that bigger size Nep!lrops are being by 13 % and biomass by 117 %. For females decreasing landed in Spanish ports of Ayamonte and Huelva. fishing effort to F max would hardly affect long-term yield (only 3 %) but would increase long-term biomass Catches from the surveys. using a trawl net, indicate by 76-48 %. Ouctuations in the mean size for both sexes however the changes may be due to different trawl cod end mesh Aged based assessments sizes used. For 1991 surveya eodend with 20 mm mesh size was used. Catch at age was estimated converting annual length distributions into 'nominal age' distributions using the Assessments slicing technique on annual length frequency distributions by sex for the period 1985-1990. Sampling levels • Males: Length eompositions of Nep!lrops catches were based on the sampIes taken from trawl landings at the most From the splitting, 'nominal ages' range from 1 to 9 (10 important fishing ports whieh have varied depending on plus group). Tables 5.18.20 and 5.18.21 show catch at the year: Olhao in 1986 and 1987 and Vila Real de Santo age and mean weight at age which were used as input to Antonio during 1988-1991. In the 1984-1986 period. the the VPA. average number of sampIes measured annually was 150 per sex; since then the average number of sampIes has Terminal fishing mortality was tuned using fishing effort decreased aehieving in 1991 the lower level of 25 data. historie F was also included. Table 5.1.4 shows the sampIes per year. In the 1984-1986 period for each tuning input choices. Tbe variances about the F values sampIe an average of 45 individuals were measured and were small compared to the tuned F values. Tables presently around 38 im.lividuals are being measured. 5.18.22 and 5.18.23 present the F at age matrix and population in numbers (thousands) ~t age respectively. No sampling of creel catches took place, however it should be emphasized that this fishery only contributes The average fishing mortality for ages 3-8 , as wen as about 2 % of the total catehes. Total Stock Biomass (TSB). Spay,ning Stock biomass 41 11 (SSB) amI log Recruitment are presented in Table vides a signifieant eorrelation. By applying the average 5.18.24. The plot of Fbar versus fishing effort, is effort for the same period to this relationship an alterna presented in Figure 5.18.6. The relationship is not tive option of 368 tonnes is obtained. It should however, statistieally signifieant and is in any case a negative be noted that the diserepancy between this and the former correlation whieh is meaningless. This could be due to a method is because of the re1atively high landings in number of reasons • For males the level of fishing recent years whieh alllie above the line. For this reason mortality (F bar) has remained relatively stable (with the the former option is suggested. exception ofthe year 1989), around a value ofO.7. 5.18.4 Gulf of Cadiz (Functional Unit 30) Females: Landings From the splitting, 'nominal ages' range from 1 to 9 (10 plus group). Tables 5.18.25 and 5.18.26 show cateh at Table 5.18.1 includes landings data for this stock updated age and mean weight at age whieh were used as input to for the years 1988 to 1990, the 1991 data were DOt the VPA. available. Landings have Ouetuated without obvious trend. Terminal fishing mortality was tuned using fishing effort data, historie F was also ineluded. Table 5.1.4 shows the There was no other information available for this stock tuning input choiees. The varianees were smaller than and no assessment was carried out. The catch option tuned F but of similar order of magnitude. Tables adopted last year was the maximum landing in the time 5.18.27 and 5.18.28 present the F at age matrix and series ie. 302 tonnes, this option is retained. population in numbers (thousands) at age respectively. Fishing mortality rates were about half those of the 5.18.5 Summary for Management Area IXa (Area males. Q) • The average fishing mortality (Fbar) for ages 3-8 , as Surnmaries of the recent landings from this Management weil as Total Stock Biomass (TSB), Spawning Stock Area are given by Functional Unit and country in Tables biomass (SSB) and log Recruitment are presented in 5.18.30 and' 5.18.31. The derivation of the overall eateh Table 5.18.29. The plot of Fbar versus fishing effort, is option for this Management Area is summarised in the presented in Figure 5.18.6. The relationship is not text table below and comprises the catch options recom statistieally signifieant although, in being positive is mended above for Units 26,27 and 28-29 together with slightly more realistie than for the males. For females F the maximum landings for Unit 30. There were DO bar values are also relatively stahle if 1984 and 1985 are landings from other Rectangles. exeluded from the analysis, with a value of 0.40. The VPA results indicate that the level of fishing mortality FU Derivation of option Total for hoth sexes has been relatively stahle although fishing landings effort has Ouetuated. (l) Catch options 26 Av. landings 1989-90 514 27 Av. landings 1987-91 70 In view of the uncertainty ahout the VPA results, the 1991 LCA results were referred to. These suggested that 28-29 Av. landings 1987-91 450 effort should be at least stabilised or possibly reduced. At • 30 Maximum landings in 302 the 1991 Working Group a value of 460 tonnes was period recornmended as the eateh option for 1991 based on 1984-1985 average cateh data because for the 1986-1990 Total 1336 period, the offieial landings figures were not reliable. During 1991 the estimated total catch for this Funetional Unit was estimated as heing 480 tonnes. 5.19 Management Area IXb and X (Area R) At present the catehes are revised for the whole period Functional Units - None and therefore a cateh option hased on the average catches during 1987-1991 (450 tonnes) may be recommended as 5.19.1 Summary of Management Area IXb and X the neW catch option. This is very elose to last year's (Arca R) recommendation. Figure 5.18.7 shows the relationship between landings and effort (Table 5.1.5), which pro Zero TAC to prevent misreporting. 42 6 TRAWL . EFFICIENC\; '. AND FISIIING 6.3 Swedish fleet ' I'OWER IN NEPllROPS FISIIERIES Following a decline in fish stocks in the Skagerrak and 6.1 Introductiml Kattegat during the 1980's more ofthe fish trawling fleet switched gear to Nephrops trawls and fishing effort on Tbere is eviuence that gear efficiency and vessel catching Nephrops increased rnarkedly. During 1989 some vessels power in Nephrops fisheries have increased in recent changed from single- to twin-rigged trawls. Tbe use of years. As a consequence of this the commonly used this gear has increased and since 1990 single and twin expressions of fishing effort in terms of time spent trawls have been separated in Swedish fishermen's fishing (hours or days fisheu, trips or lanuing days) are 10gbooks. In 1990 twin trawls accounted for 18 % of the likely to underestimate effort and distort long term trends trawling effort and by 1991 the use of this gear had in effort, epUE and LPUE. Increases in eatching power increased to 37 % of the effort. Tbe eorresponding can arise through increases in vessel size and engine proportions ofthe Nephrops landings were 28 %and 53 % horse-power (HP), leauing to the use of larger nets. in 1990 and 1991 respectively. Recently these developments have led to the introduction of multi-rig trawls (twin or tripie nets) with greater Seasonal variations in LPUE for different gear types in eatching power than single trawls. Tbe better catching the period 1990-91 are shoMl in Figure 6.1 and these power of multi-rig trawls has improved the econornie data have been replotted in Figure 6.2 in order to viability ofNephrops fishing for much larger vesse1s than compare LPUE values derived from single and twin hitherto. Multi-rig gears are currently in use to varying trawls. Tbe LPUE ratio for twin/single trawls is esti extents in the following Nephrops Functional Units: 1 mated (from the slope of the Hne in Figure 6.2) to be (few vessels), 3-4, 5 (by Danish fleet only), 7-13, 15 1.7. In the Swedish fishery, where no other fishing (< 1% of vessels) and 23-24. power parameters (eg. HP) have changed, it should be • possible to convert effort and LPUE data to a "standard" Although there is little detailed information on changes gear equivalent for the future analyses of time trends. in catching power for many fisheries some data are available for se1ected fleets. Vesse1 HP has been routine 6.4 Fleet and fishing gcar de\'Clopments in Seot Iy used in the derivation of effort and LPUE indices for land N. Irelanu and Spanish vessels. Examples for FU's 16, 25 and 31 may he found in Tables 5.13.2,5.16.2 and 6.4.1 Fh.'Ct suncy 5.6.15 respectively. In 1990 a random survey was eonducted in the North 6.2 Northern Ircland fleet Minch to provide information on vessel capacity and fishing gear used in the Nephrops fishery (Bundy, 1990). Fishing effort, epUE and LPUE data for the N. Ireland By means of a detailed questionnaire information was Nephrops fleet fishing the Irish Sea grounds are pres obtained from 90 skippers on their vessel HP, length and ented in Table 6.1. Two sets ofepUE and LPUE indices tonnage, and type and size ofgear used past and present. are given, with and without incorporation of data on Landings records for these vessels between 1986 and average Vessel HP. There has apparently been little 1989 in one statistical square were also exarnined . change in vessel HP (average = 250.8; SD = 12.9) over Figure 6.3 shows that since 1959 there has been a the reference period in which case either data set could significant increase in average HP of vessels hut their • be used for assessment purposes. mean length has declined. The use of multi-rig trawls in the Irish Sea has been The gear survey was complicated by the fact that some restricted by local agreement amongst fishermen. vessels used more than one type each year but a general picture emerged of the historical trends. Six gear types A factor which may have influenced CPUE and LPUE were identified based on rigging and ground gear design indices for this fleet in recent years is a gradual change (see Table 6.2 for brief description) and the ehanges in in fishing practice towanls longer voyages which inc1uue their use are shoMl in Figure 6.4. Until 1963 all vessels night fishing. Over the depth range of most grounds, used grass ropes but rubber dise and bobbin types were eatch rates during darkness are low due to the burrowing popular from the late 1960's until rockhopper gear was behaviour of Nephrops. Because night catches cannot be introduced in the 1980s. Bobbin and rockhopper gears distinguished from day catches the effect is to depress the are used in areas where mud patches are interspersed overall estimates ofepUE/LPUE. This point is discussed with hard ground. Twin or tripie net rigs with rubber further below. dise or rockhopper ground gear are recent developments. In 1990 a11 gear types were still represented but rubber dise and rockhopper gear were being used by 80%ofthe vessels in the survey (Table 6.2). In addition to the 43 possible effect of HP, catch rates of vessels shoulll (Table 6.3). Since 1991 multi-rig trawls have been depend on the width of the gear whieh in turn may relate recorded as aseparate category in Scottish landings and to the length of the ground gear. Figure 6.5 shows, for effort statisties. A comparison between LPUE of single four different gears, the historieal treml in mean ground ami multi-rig trawls based on 1991 statistics is given in gear h:ngth (GGL) ami vessel HP. For vessels using Table 6.4. Tbe proportion of vessels using multi-nets in rubber dise ground gear there has been a significant 1991 seems to vary widely, from 85% at Fladen to only increase in GGL to match the rise in HP but this was not 3 % in the North Minch. Overall, multi-net LPUE seems the case for bobbin gear (Figure 6.5A,B>. Note the to be about 50% higher than for single trawls. It must be larger mean HP ami GGL for vessels using twin-rig remembereu that multi-nets are generally used by larger, trawls (Figure 6.5D). For the current fleet (in 1990) the high HP vessels (Figure 6.5) and at present it is not survey data showed a strong correlation between GGL possible to separate the gear and vessel effects. Tbere and HP in the case of vessds using rubber disc, have also been teething problems with the classification rockhopper and twin trawls. of gears at some ports leading to under-reporting of multi-nets. 6.4.2 LllUE in relation to "csscl und gcar charac teristics 6.5 Conclusions For vessels in the fleet survey, landings and effort (hours Fishing effort forms a major component in the assess fishing) data were extracted from official statistics ments through its employment in the estimation offishing covering the most heavily fished ICES statistieal square mortality (VPA tuning and mean F plots), the prediction in the North Minch during 10 quarters between 1986-89. of catch options and the estimation of stock biomass A summary of LPUE data according to gear type is indices (epUE, LPUE indiees). Tbe W/G eonsidered given in Table 6.3. Tbis indicates lillie difference that improvements in the recording and analysis of between recent lamling rates of nets filled with bobbin, fishing effort data were desirable. Tbe fact that most • rockhopper and rubber disc ground gear but suggests a grounds supported mixed fish and Nephrops fisheries marked increase in LPUE using twin trawls (see bdow). sometimes created difficulties in the allocation of effort. A preliminary multiple regression analysis of the data Tbe choiee of units was also problematical. Recent was carried out to determine possible relationships fishing practices in Northern Ireland led to doubts about between LPUE and vessel/gear characteristics. Tbis the suitability of 'hours fishing' as a measure of effort. indicated a significant 'boat' effect in the case of two Since the emergence of Nephrops was periodic, usually gears for which there was sufficient data (Table 6.2, confined to a few hours per day, catches were not a types 2 & 4), with most of the variation being explained simple linear function of hours fishing. Days fishing by vessd HP. Further analyses of this data are planned would probably represent a better measure and might be but on the assumption that vessels in the survey were easier to collect. On the question of changes in vessel reasonably representative of the whole North Minch fleet and gear characteristics the Working Group would a correction for HP derived from Figure 6.3 has been welcome guidance from technieal experts in this field, applied to the historieal LPUE data series for this area in for example the ICES Working Group on Fishing Figure 5.4.3. In the period 1965-1991 Figure 6.3A Technology and Fish Behaviour. It was also suggested shows that average vessd HP in the North Minch fleet that the topie of fishing effort measurement should be increased from about 146 to 236 (ie. by a factor of considered further by the ICES Nephrops Study Group. 1.62). A correction for the change in HP since 1965 was obtained by dividing the annual mean LPUE by a factor derived from: (mean HP in year n)/(mean HP in 1965). 7 TRANSFER OF WORK TO AREA BASED • Figure 5.4.3 shows that inclusion of vesselHP informa WORKING GROUPS tion makes a noticeable difference to LPUE trends in the North Minch fishery. The uncorrecteu data set show Tbe Working Group had a lengthy discussion on the large fluctuations in LPUE with a suggestion of a slight transfer of the Nephrops and Palldalus assessments to upward trend, conversely, the corrected set are less area based Working Groups, and on the future role of variable and suggest a slight downward trend. the newly established Study Groups on Nephrops and Palldalus. 6.4.3 Comparison hctW(~cn single- und multi-rig Nephrops trawls The Working Group fully recognizes the benefits ofareal Working Groups, in dealing with the biologieal, technical Tbe above fleet survey showed that multi-rig (mostly and management aspects ofmixed fisheries, and ultimate twin) trawls wem introJuceJ into the North Minch ly, in Joing multi-species assessments. Nevertheless the fishery in 1985 (Figure 6.4). In 1990 about 13% of Working Group felt that the eurrent stale of especially Nephrops trawlers in this area wen~ using this gear the Nephrops assessmenls is such that a precipitate (Table 6.2) and eatch rates appeared to be much higher transfer of its tasks to the area based \Vorking Groups 44 may not be wise. entire functional units, regardless whether' they extend into neighbouring areas (which may weil be the case for Considerable progress has been made over the past four the stocks near the "borders" between the Northem and years in assessing Nephrops stocks. LCA was first Southem Shelf Areas). introduced for management purposes at the Lowestoft meeting of the Working Group in 1989. Since then the The Working Group welcomes the establishment of the technique has been refined, and it has been employed to Study Groups on Nephrops and Pandalus. Both Study carry out yield per recruit assessments for almost all Groups will be extremely useful in reviewing the biologi Nephrops stocks. Last year the Working Group experi cal data on Nephrops and Palldalus, and in updating the mented with age based assessment techniques, and biological parameters to be used in the areal assessment attempted to take this a stage further at this Working Working Group. The Study Groups will also provide an Group. excellent means to explore new assessment techniques, or to improve the existing ones. Several aspects however, all c10sely related to this method, need to be fully investigated, before the tech The exchange of views and information between Study nique can be considered as being sufficiently sound to be Groups and areal Working Groups would benefit from a used for routine assessments ofNephrops. These include regular attendance at the areal Working Group meetings by Study Group members. Therefore ICES is asked to play an active role in stimulating national bodies to send a. the application ofother slicing techniques, which their Nephrops and Pandalus experts to the areal Work may perform better than the one used during this ing Group meetings. meeting, and/or the improvement of the existing technique, some trials with the Mohn method The frequency of the Study group meetings will depend • (see Section 4) would be a useful skp; on the state of progress of their specific tasks. Neverthe less it is aJvisable to schedule their meetings weil in b. the sensitivity of the age based assessments to advance, preferably one year ahead. Many institutes are variations in input parameters and age groups, bound by increasingly tight budgets for travelling, whieh and to the choiee of the tuning options; leaves little room for short-term planning. c. the preJiction of catches and lanJings from the output of the VPA; 8 NEXT VENUE d. the cross-correspondence between the outputs of On behalf of the Fisheries Research Station in astende, the length and age based assessments, and of any Belgium, F. Redant, member of the Working Group, other indices of the state of exploitation, such as invited the Working Group to have its next meeting in trends in LPUE or mean size of Nephrops astende. laOlled ; and e. the set-up of standard procedures for Nephrops 9 REFERENCES sampling, and for collating input length and age distributions, comparable to the methods used by Anon. (1977). Report of the Working Group on the most finfish Working Groups. Assessment of Pandalus Stocks. ICES, Doc. • C.M. 1977/K:1O (mimeo). The Working Group is convinced that it can make a substantial contribution in clearing these fields, and Anon. (1989). Report of the Working Group on would appreciate being given sufficient time to complete Nephrops Stocks. ICES Doc. C.M. this task. 1989/Assess: 18(mimeo). The Working Group also considered the allocation of Anon. (1990a). Report of the Working Group on Nephrops and Pandaltls stocks to the newly-established Nephrops stocks. ICES Doc. C.M. 1990/Assess: areal Working Groups. The resulting proposal for 16 (mimeo). allocation is summarized in Table 7.1, together with information on the type of assessments currently being Anon. (1990b). Report of the Working Group on the applied to each stock (either single- or multi-fleet), and Assessment of Pandalus Stocks. ICES, Doc. on the number of Working Group members involved in C.M. 1990/Assess: 9 (mirneo). doing the assessments. Anon. (1991a). Report of the Working Group on the It should be c1ear that the allocation proposal refers to Assessment of Nephrops Stocks. ICES, Doc. 45 r------ C.M. 199I1Assess: 11 (mirneo). GuJmundsson,O (1987). Time series analysis of fishing mortality rates. ICES, Doc. C.M. 1987/D: 6 Anon. (199Ih). Report of the Working Group on (mirneo). I\fethoJs of Fish Stock Assessment. ICES, Doc. C.M. 1991/Assess: 25 (mimeo). HiIlis, J.P. (1979). Growth studies on the prawn Nephrops norvegicus. Rapp. P.-V. Reun. Cons. Anon. (199Ic). Report of the Working Group on the int. Explor. Mer.,175,170-175. Assessment of PllIulalus Stocks. ICES, Doc. C.M 199I1Assess: 8 (mirneo). HiIlis, J.P. (1987). A study of the catch composition in the Irish Nephrops fishery with special attention Briggs, R. (1985). Catch composition in the Northern to growth and maturity. ICES, Doc. Shellfish IrelanJ Nephrops Fishery Fisheries Research, 3, Comm., CM 1987/K: 22 (mirneo). 47-60. Mohn, R.K. and Savard, L.(1989). Length based Briggs, R. (1988). A preliminary analysis of maturity population analysis of Sept-lIes shrimp (Gulf of uata for Northwest Irish Sea Nephrops. ICES, St. Lawrence). NAFO SCR- Res. Doe 89/92. pp Doc. SheIlfish Comm., C.M. 1988/K: 21 1-14. (mirneo). Pope, J. and Thomas, H.J. (1955). Some biometrie BunJy, A. (1990). A stuJy ofthe North Mineh Nephrops observations on Nepllrops lIorvegicus (L). ICES, fishery. MSc Thesis, University College of Shellfish Comm., 1955, paper no.180 (mimeo). North Wales, U.K. pp 1-97. Skuladottir, U. (1981). The deviation method. a simple Daan, N. (1991). Consumption of Pandaltls in the North method for detecting year c1asses ofa population • Sea by MSVPA preJators. ICES, Doc. SheIlfish of Pandalus borealis from length distributions. Committee C.M. 1991/K: 26 (mimeo). Proc. of the International Pandalid Shrimp Symposium, Feb. 13-15, 1979, Kodiak Alaska. Eiriksson, H. (1979). A stuJy of the leelanuic Nephrops Sea Orant Report 81 pp 283-307. fishery with emphasis on stock assessments. Rapp. P.-v. Reun.Cons int.Explor.Mer, Sullivan, P.J. Lai, H.L. anu Gallucci, V.F. (1990). A 175:270-279. cateh-at-Iength analysis that incorporates a stochastic model of growth. Can J. Fish Aquat Eiriksson, H. (1982a). A trial VPA on the Nepllrops Sei 47:184-198. stock at IcelanJ with comparison to errort uata. ICES, Doc. C.M. 1982/K: 17 (mirneo). Tully, 0., Hillis, J.P. and McMulIan, D. (1989). Fitting normal curves to polymodal length frequencies Eiriksson, H. (1982h). Estimating the Growth of to assess growth in Nephrops. ICES, Doc. C.M. Nephrops at Icelanu. ICES CM 1982/K: 1989/K: 32 (mimeo). 16(mimeo). Eiriksson, H. (1992). A synopsis of age baseu assess ments on Nephrops at leeland. Working Paper • suhmitteu to the ICES Working Group on the assessment of Nephrops ami Pandalus 1992. pp 1-5. 46 47 Table 3.3.1 Pandalus borealis landings from Divisions lIla (Skagerrak) and IVa (eastern part) (Norwegian Deeps) as estimated by the Working Group. Year Denmark Norway Sweden Total 1970 1,102 1,729 2,742 5,573 1971 1,190 2,486 2,906 6,582 1972 1,017 2,477 2,524 6,018 1973 755 2,333 2,130 5,218 1974 530 1,809 2,003 4,342 1975 817 2,339 2,003 5,159 1976 1,204 3,348 2,529 7,081 1977 1,120 3,004 2,019 6,143 1978 1,459 2,440 1,609 5,508 1979 1,062 3,040 1,787 5,889 1980 1,678 4,562 2,159 8,399 1981 2,593 5,183 2,241 10,017 1982 3,766 5,042 1,450 10,258 1983 1,567 5,361 1,136 8,064 1984 1,747 4,783 1,022 7,552 1985 3,827 6,646 1,571 12,044 • 1986 4,834 6,490 1,463 12,787 1987 4,599 8,343 1,321 14,263 1988 3,068 7,661 1,278 12,007 1989 3,150 6,411 1,433 10,994 1990 2,479 6,139 1,540 10,158 1991 3,583 6,106 1,917 11,606 • 48 Iable 3.3.2 Catch (tannes) and e[[art by fleet, year and quarter [ar Pandalus barealis in Div.IIIa and IVa E Denmark Norway Sweden Quarter Catch· effort Catch effort Catch cffort Year (t) days (t) (Khrs) (t) (Khrs) 1 336 827 1402 183 8.6 2 264 898 1053 no 234 12.4 3 800 1410 1751 data 393 11.3 4 347 735 577 213 8.0 1984 1747 3869 4783 1022 40.2 1 410 1002 1679 208 7.4 2 909 1476 2051 no 491 17.0 3 1482 1688 1600 data 484 14.5 4 1026 1160 1316 387 10.1 1985 3827 5326 6646 1571 48.9 1 914 1451 1661 40.8 282 8.3 2 1656 3482 1660 50.9 500 18.8 • 3 1464 2343 1664 47.4 383 12.4 4 800 1424 1505 40.0 299 9.7 1986 4834 8700 6490 179 1463 49.2 1 1069 2192 2687 57.5 328 11.3 2 1511 3188 2722 77.5 388 19.3 3 1051 1952 1336 37.3 312 14.1 4 968 1880 1598 57.7 293 12.5 1987 4599 9212 8343 230 1321 57.2 1 1111 2296 2675 61.4 296 11.5 2 1094 2616 2254 78.0 429 20.6 3 502 1240 1623 61.2 268 12.1 4 361 953 1109 50.0 285 12.7 1988 3068 7104 7661 251 1278 56.9 1 529 1545 1707 58.9 297 13.0 • 2 1037 2633 1476 70.6 461 21.9 3 1111 2039 2071 80.6 391 14.6 4 473 1260 1157 63.2 264 13.4 1989 3150 7477 6411 273 1413 62.8 1 373.1 650 1454 39.4 346 10.4 2 649.7 1554 1777 84.8 333 18.8 3 884.6 1161 1568 57.6 509 15.8 4 571.7 871 1340 50.0 354 13.3 1990 2479 4236 6139 232 1542 58.3 1 764 1317 1759 51.2 494 14.4 2 1024 1932 1338 55.8 497 18.4 3 991 1194 1751 58.9 516 15.0 4 804 1044 1258 40.9 411 13.2 1991 3583 5487 6106 207 1917 61.0 49 Table 3.3.3 Virtual Population Analysis. Catch in numbers at age. Pandalus borealis in Div.llla and IVa E Run title Pandalus lIla + IVb Assessment Traditional vpa Terminal Fs estimated using laurec/Shepherd method Table Catch numbers at age Nl.ITbers* 10** - 6 YEAR 1985 1986 1987 1988 1989 1990 1991 AGE 1 742 875 869 447 1124 1291 1078 2 1249 969 947 599 522 931 1096 3 246 537 561 380 323 124 295 4 111 34 116 222 44 32 29 +gp 0 2 12 0 0 3 0 TOTAlNUM 2348 2417 2505 1648 2013 2381 2498 TONSLAND 12044 12787 14263 12007 10994 10129 11443 SOPCOF % 96077 96351 110455 111617 101530 99123 100568 • Table 3.3.4 Virtual Population Analysis. Catch weights at age (kg). Pandalus borealis in Div.llla and IVa E Run title Pandalus lIla + IVb Assessment • Traditional vpa Terminal Fs estimated using Laurec/Shepherd method Table 2 Catch weights at age (kg) YEAR 1985 1986 1987 1988 1989 1990 1991 AGE 1 0.0030 0.0033 0.0026 0.0029 0.0034 0.0030 0.0031 2 0.0054 0.0056 0.0045 0.0054 0.0066 0.0053 0.0051 3 0.0092 0.0085 0.0086 0.0091 0.0093 0.0082 0.0071 4 0.0123 0.0125 0.0116 0.0127 0.0128 0.0104 0.0099 +gp 0.0163 0.0161 0.0142 0.0000 0.0000 0.0137 0.0000 50 Table 3.3.5 Virtual Population Analysis. Tuning input file. Pandalus borealis in Div.llla and IVa E PANDALUS 111A-1V TUNING 103 DENMARK 85,91 1,1 1,5 5394,274,405,54,16,0 8701,342,362,203,11,.2 9212,300.5,297.7,171.5,35.6,3.2 7105,41.8,305.8,144.6,45.2,0 7478,221.7,110.5,51.9,10.7,0 • 4236,447.8,247.6,10.6,0,0 5487,316,416,69,3,0 NORUAY 86,91 1,1 1,5 176.4,435.9,496.8,268.4,18.6,1.2 258.2,483.6,565.1,339,70.6,7.5 260.8,329.1,235.5,197.7,155.4,0 274.2,783.1,323,236.8,26.1,0 231.8,752,548,79.4,29.5,2.6 206.8,658.6,510.2,171.8,22,0 SUEDEN 85,91 1,1 1,5 49.0,107.5,170.9,25.2,8.4,0.01 49.2,97.3,110.5,65.0,4.0,0.18 57.1,85.1,84.0,50.2,10.0,0.9 • 56.9,75.6,57.9,37.8,21.6,0.11 62.8,119.8,88.3,34.1,7.5,0.00 58.3,90.9,135.4,33.2,2.6,0.2 61.0,103.8,170.3,54.7,3.9,0 51 Table 3.3.6 Virtual Population Analysis. Tuning output. Pandalus borealis in Div.llla and IVa E VPA Version 2.1 - May 1988 Pandalus lila + IVb Assessment with cpue data from file r.pandlpan3aef92.dat DISAGGREGATED Qs lOG TRANSFORMAT ION NO explanatory var i ate (Mean usedl Fleet 1 ,DENMARK has terminal q estimated as the mean Fleet 2 ,NOR'OAY , has terminal q estimated as the mean Fleet 3 ,S'OEDEN , has terminal q estimated as the mean flEETS COMBINED BY VARIANCE ** Terminal Fs estimated using laurec/Shepllerd method Regression weights , 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000 Oldest age F = 1.000"average of 2 younger ages. Fleets cOfTbined by variance of predictions Fishing mortalities Age, 1985, 1986, 1987, 1988, 1989, 1990, 1991 0.088, 0.187, 0.233, 0.179, 0.214, 0.176, 0.172 2," 0.433, 0.291, 0.616, 0.473, 0.637, 0.530, 0.415 3, 0.821, 0.665, 0.524, 1.200, 1.096, 0.597, 0.627 4, 0.627, 0.478, 0.570, 0.836, 0.867, 0.563, 0.521 Log catchabi l ity es t hlBtes Age 1 Fleet, 1985, 1986, 1987, 1988, 1989, 1990, 1991 ---'---'---'---'---'---'---'--- ,'12.02,' 11.69,'11.65, - 12.96, '12.08,' 11.15,'11.60 • 2 , , '7.55, -7.60, '7.59, -7.52, '7.73, '7.59 3 , -8.25, '7.77, -7.83, '7.54, -7.92, -8.46, -8.21 SUMMARY STATISTICS Fleet Pred. ,SE(ql,Partial,Raised, SlOPE SE ,I NTRCPT , SE q FF Slope , ,lntrcpt ---,---,---,---,---,------,---,--- 1 ,'11.88 , 0.606,0.0381 ,0.1300, O.OOOE+OO, O.OOOE+OO,·" ,877, 0.214 2 , -7.59 , 0.078,0.1042 ,0.1705, O.OOOE+OO, O.OOOE+OO, '7.594, 0.029 3 , '8.00 , 0.344,0.0205 ,0.2133, O.OOOE+OO, O.OOOE+OO, -7.996, 0.122 Fbar SIGMA(int.l SIGMA(ext.l SIGMA(overalll Variance ratio 0.172 0.755E·01 0.419E·01 0.755E·Ol 0.308 Age 2 Fleet, 1985, 1986, 1987, 1988, 1989, 1990, 1991 ---'---'---'---'---'---'---'--- 1 " 10.56,'11.29,'10.77,·10.29,·10.92,·10.31,·10.46 2 , , -7.08, -6.56, -7.25, '6.54, '6.61, '6.98 3 , '6.72, '7.30, '6.95, '7.13, '6.37, '6.63, '6.85 SUMMARY STATlSTICS Fleet Pred. ,SE(q),Partial,Raised, SLOPE SE ,I NTRCPT , SE • q FF Slope , ,Intrcpt ---,----,---,---,---,------,---,--- 1 ,'10.66 ,0.388,0.1291 ,0.3402, O.OOOE+OO, 0.000E+00,-10.657, 0.137 2 ,-6.83 ,0.327,0.2225 ,0.4780, O.OOOE+OO, O.OOOE+OO, '6.835, 0.124 3 ,-6.85 ,0.335,0.0646 ,0.4160, O.OOOE+OO, O.OOOE+OO, -6.850, 0.119 Fbar SIGMA(int.) SIGMA(ext.) SIGMA(overalll Variance ratio 0.415 0.201 0.950E-Ol 0.201 0.225 Age 3 Fleet, 1985, 1986, 1987, 1988, 1989, 1990, 1991 ---'---'---'---'---'---'---'--- 1 ,-10.31, '10.45,'10.96, '9.65, -10.66,'11.33, '10.53 2 , '6.27, -6.70, '6.03, '5.83, -6.41, -6.34 3 , -6.37, -6.42, -7.10, -6.17, -6.30, -5.90, -6.26 SUMMARY STATISTICS Fleet, Pred. ,SE(ql,Partial,Raised, SLOPE SE ,INTRCPT, SE q FF Slope , ,Intrcpt ---,---,---,---,---,------,---,--- 1 ,'10.55 ,0.562,0.1430 ,0.6115, O.OOOE+OO, O.OOOE+OO, -10.555, 0.199 2 ,-6.27 ,0.327,0.3931 ,0.6750, O.OOOE+OO, O.OOOE+OO, '6.265, 0.124 3 ,-6.36 ,0.395,0.1056 ,0.5694, O.OOOE+OO, O.OOOE+OO, -6.359, 0.140 Fbar SIGMA(int.l SIGMA(ext.) SIGM~.(overalll Variance ratio 52 0.627 0.230 0.545E-Ol 0.230 0.056 Table 3.3.7 Virtual Population Analysis. Fishing mortality at age. Pandalus borealis in Div.llla and IVa E Run title Pandalus lIla + IVb Assessment Traditional vpa Terminal Fs estimated using laurec/Shepherd method Table 8 Fishing mortality (F) at age YEAR 1985 1986 1987 1988 1989 1990 1991 FBAR 86-90 AGE 1 0.0884 0.1872 0.2327 0.1790 0.2143 0.1755 0.1716 0.1978 2 0.4325 0.2909 0.6156 0.4729 0.6375 0.5296 0.4153 0.5093 3 0.8209 0.6651 0.5242 1.2000 1.0956 0.5969 0.6269 0.8164 4 0.6267 0.4780 0.5699 0.8365 0.8665 0.5633 0.5211 0.6628 +gp 0.6267 0.4780 0.5699 0.8365 0.8665 0.5633 0.5211 FBAR 1- 3 0.4473 0.3811 0.4575 0.6173 0.6491 0.4340 0.4046 FBAR 2- 3 0.6267 0.4780 0.5699 0.8365 0.8665 0.5633 0.5211 Table 3.3.8 Virtual Population Analysis. Stock number, total and spawning biomass. Pandalus borealis in Div.llla and IVa E Run title Pandalus lila + rVb Assessment At 16:28:34 on 26-MAR-92 Traditional vpa Terminal Fs estimated using laurec/Shepherd method Table 10 Stock number at age (start of year) Numbers*10**- 6 YEAR 1985 1986 1987 1988 1989 1990 1991 1992 AMST 86-90 AGE 1 12397 7201 5865 3834 8173 11276 9615 0 7270 2 4924 5360 2821 2195 1514 3116 4469 3826 3001 3 594 1509 1893 720 646 378 867 1394 1029 • 4 326 124 367 529 102 102 98 219 245 +gp 0 7 38 0 0 10 0 28 TOTAL 18241 14201 10983 7278 10436 14882 15049 5465 TOTALBIO 73 68 49 36 45 55 60 '000 tonnes TOTSPBrO 19 13 18 12 10 12 18 '000 tonnes 53 Table 3.3.9 Indices of 0- and I-group shrimp from Norwegian trawl surveys in Getober, VPA values and regression equations Survey VPA Year-class O-gr (Illa) l-gr(IIIa) l-gr 2-gr 1983 7023 4948 1984 3077 20902 12397 5360 1985 1813 6914 7201 2821 1986 1432 5988 5865 2195 1987 675 2541 3834 1514 1988 2002 8714 8173 3116 1989 9388 10743 11276 3852 1990 4052 12116 9923 4142 1991 1877 7116 Bold figures estimated from the following equations: Ln (VPA 2-gr)= 0.604ln(l-gr index) + 2.65 Ln (VPA l-gr)= 0.432In(0-gr index) + 5.614 For 1989 and 1990 year-class VPA estimates for 2-group were 4469 and3826 For 1990 the VPA l-gr estimate is 9615 • 54 Table 3.3.10 Pandalus borealis lIla and IVa E. Prediction input. PANDALUS IN SKAGERRAK (lIlA) AND NORWEGIAN DEEP (IVA E) The reference F is the mean F (non weighted) for the age group range 1 to 3 The number of recruits per year is as follows: Year Recruitment 1992 7116 1993 7270 1994 7270 Proportion of F (fishing mortality) effective before spawning: .200 Proportion of M (natural mortality) effective before spawning: .250 Data are printed in the following units: Number of fish: millians Weight by age group in the catch: gram Weight by age group in the stock: gram Stock biomass: tannes Catch weight tannes fishing natural maturity Wt in the Wt in the age stock size pattern mortality ogive catch stock 1 7116 0.16 0.75 .00 3.016 3.016 2 4142 0.41 0.75 0.73 5.392 5.392 3 1394 0.65 0.75 1.00 8.442 8.442 4 219 0.53 0.75 1.00 11. 476 11. 476 • 5+ 27 0.53 0.75 1. 00 13.930 13.930 55 • f. • , Table 3.3.11 Pandalus borealis lIla and IVa E. Prediction results. Effects of different levels of fishing mortality on catch, stock biomass and spawning stock biomass. PANDALUS IN SKAGERRAK (lIlA) AND NORWEGIAN DEEP (IVA E) Year 1992 Year 1993 Year 1994 factor ref stock sp.stock factor ref stock sp.stock stock sp.stock F biomass biomass catch F biomass biomass catch biomass biomass 1.0 0.4 58 23 13 .0 .00 53 23 0 62 29 .2 .08 22 3 59 26 .4 .16 22 5 57 24 .6 .24 21 7 54 22 .8 .32 21 9 52 20 1.0 .40 20 11 51 18 1.2 .49 20 13 49 17 1.4 .57 19 15 47 15 1.6 .65 19 16 46 14 1.8 .72 19 18 45 13 2.0 .81 18 19 43 12 The data unit of the biomass and the catch is 1000 tonnes. The spawning stock biomass is given for the time of spawning. The spawning stock biomass for 1993 has been calculated with the same fishing mortality as for 1992. The reference F is the mean F (non-weighted) for the age group range from 1 to 3. Table 3.4.1 Landings (t) of Pandalus borealis from the Fladen Ground (Division IVa) as estimated by the Working Group. Year Denmark Sweden Norway UK (Scotland) Total 1972 2,204 187 2,391 1973 157 163 320 1974 282 434 716 1975 1,308 525 1,833 1976 1,552 1,937 3,489 1977 425 112 1,692 2,229 1978 890 81 2,027 2,998 1979 565 44 268 877 1980 1,122 76 377 1,575 1981 685 1 347 1,033 1982 283 352 635 1983 5,729 8 1,827 7,564 1984 4,553 13 25 4,591 1985 3,649 1,341 4,990 1986 3,416 301 3,717 1987 7,326 686 8,012 1988 1,077 2 84 1,163 1989 2,438 25 547 3,010 1990 6 1,681 4 3 365 2,053 1991 422 53 475 6Provisional Table 3.4.2 Pandalus borealis, Fladen Ground. Reported CPUE (shrimp trawlers), and estimated total effort. • UK (Scotland) Denmark Year CPUE Total effort CPUE Total effort Combined 1 1 2 (t per day) (Days) Index (kg per hour) (hours) Index index 1982 0.96 295 0.10 74 4757 0.31 0.22 1983 1.18 4855 1. 61 89 20528 1.32 1.54 1984 0.97 4694 1.56 37 676 0.04 1.55 1985 1.21 3016 1.00 86 15593 1. 00 1.00 1986 0.96 3558 1.18 71 4239 0.28 1.11 1987 1.24 5908 1. 96 81 8469 0.54 1. 84 1988 0.83 1298 0.43 44 1909 0.12 0.41 1989 0.99 2463 0.82 65 8415 0.54 0.77 1990 1.28 1313 0.44 106 3443 0.22 0.40 1991 1. SO 281 0.09 124 429 0.03 0.08 lRelative to 1985. 2Weighted by total landings. 57 Table 3.4.3 Pandalus. Quarterly CPUE and effort indices, Fladen Ground. Denmark UK (Scotland) Year Quarter CPUE Total CPUE Total Combined 1 1 2 (tlday) catch f Index (kg/h) catch f Index index 1984 1 1.27 2,809 2,212 1.68 1.68 2 0.75 1,407 1,876 1. 43 37 25 676 0.21 1.41 3 0.57 273 479 0.36 0.36 4 0.56 63 113 0.09 0.09 1985 1 1. 16 1.742 1.502 1.14 72 359 4.986 1.58 1.22 2 1.24 1.617 1,304 0.99 88 770 8,750 2.78 1.57 3 1.47 289 197 0.15 114 212 1,869 0.59 0.34 4 .. 0.04 0.1 3 0.002 0.002 1986 1 1. 12 1,130 1,009 0.77 72 80 1,111 0.35 0.74 2 0.89 833 936 0.71 68 150 2,206 0.70 0.71 3 0.94 1,255 1,335 1.02 77 71 922 0.29 0.98 4 0.71 200 282 0.21 0.21 e 1987 1 1. 21 2,336 1,931 1.47 89 131 1.473 0.47 1. 42 2 1.20 2,643 2,203 1.68 79 509 6,443 2.05 1. 72 3 1.43 2,014 1,408 1.07 78 45 577 0.18 1.05 4 0.89 333 374 0.28 0.28 1988 1 0.886 637 719 0.55 45.7 2 40 0.01 0.54 2 0.775 366 434 0.33 43.5 76 1,744 0.55 0.37 3 0.748 37 49 0.04 0.04 4 0.466 37 79 0.06 0.06 1989 1 0.916 546 596 0.454 53 24 453 0.144 0.44 2 0.924 1,088 1,177 0.896 57 302 5,298 1.683 1.067 3 1.273 671 527 0.401 83 221 2,663 0.846 0.511 4 0.732 133 182 0.138 - 0.138 1990 1 1.59 201 126 0.10 - 0.10 2 1.26 1,436 1,132 0.86 104.6 350 3,345 1.06 0.90 3 0.52 44 84 0.06 151.0 148 148 0.31 0.25 4 • 1991 1 1. 56 57 36 0.03 72.8 6 82 0.03 0.03 2 1.47 336 229 0.17 135.6 47 348 0.11 0.16 3 4 1.64 29 18 0.01 0.01 lRelative to average effort in first-third quarters in 1985-1987. 2Weighted by total landings. 58 Table 3.4.4 Pandalus. Fladen Ground. 1991 Mean carapace lengths (mm) at age and proportions at age. Estimated by the Bhattacharya method. Quarter Year 2 4 class Age DK-samples DK-samples1 1991 0 x 9.57 prop. 0.04 1990 1 x 12.29 17.03 prop. 0.10 0.61 1989 2 x 17.29 21.09 prop. 0.49 0.35 1988 3 x 20.63 prop. 0.41 1Survey data 59 Table 3.4.5 Virtual Population Analysis. Catch in numbers at age. Pandalus borealis in Fladen Ground (IVa). Run title Pandalus FLADEN Assessment Traditional vpa Terminal Fs estimated using Laurec/Shepherd method Table Catch numbers at age Numbers*10**- 6 YEAR 1984 1985 1986 1987 1988 1989 1990 1991 AGE 1 312 354 359 540 16 306 43 10 2 597 875 586 1475 313 327 480 50 3 286 195 160 165 31 201 23 43 +gp 0 0 0 0 0 0 0 0 TOTALNUH 1195 1424 1105 2180 360 834 546 103 TONSLAND 4591 4990 3717 8012 1163 3010 2053 475 SOPCOF X 115709 118258 107768 117414 100422 98764 99515 99794 Table 3.4.6 Virtual Population Analysis. Catch weights at age (kg). Pandalus borealis in Fladen Ground (IVa). Run title Pandalus FLADEN Assessment Traditional vpa Terminal Fs estimated using Laurec/Shepherd method Table 2 Catch weights at age (kg) YEAR 1984 1985 1986 1987 1988 1989 1990 1991 AGE 1 0.0013 0.0018 0.0017 0.0017 0.0021 0.0023 0.0018 0.0013 2 0.0033 0.0031 0.0034 0.0034 0.0031 0.0040 0.0039 0.0039 3 0.0056 0.0043 0.0053 0.0053 0.0051 0.0051 0.0058 0.0063 +gp 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 60 • Table 3.4.7 Virtual Population Analysis. Tuning input file. Pandalus borealis in Fladen Ground (IVa). PANDALUS FLADEN TUNING 101 UK-OK 84,91 1,1 1,4 1547,312,597,286,0 1000,354,875,195,0 1106,359,586,160,0 1837,540,1475,165,0 408,16,313,31,0 766,306,327,201,0 397,43,480,23,0 86,10,50,43,0 Table 3.4.8 Virtual Population Analysis. Tuning output. Pandalus borealis in Fladen Ground (IVa). VPA Version 2.1 - May 1988 Pandalus FLADEN Assessment with cpue data from file [.panfllpanflef92.dat DISAGGREGATED Qs LOG TRANSFORMATION NO explanatory variate (Mean used) Fleet 1 ,UK-DK , has terminal q estimated as the mean FLEETS COHBINED 8Y ** VARIANCE ** Terminal Fs estimated using laurec/Shepherd method Regression weights , 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000 Oldest age F =1.000*average of 1 younger ages. Fleets combined by variance of predictions Fishing rnortalities Age, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991 1, 0.068, 0.114, 0.074, 0.128, 0.009, 0.039, 0.016, 0.004 2, 0.461, 0.713, 0.726, 1.479, 0.239, 0.611, 0.182, 0.051 3, 0.461, 0.713, 0.726, 1.479, 0.239, 0.611, 0.182, 0.051 Log catchabilityestimates Age 1 Fleet, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991 ---'---'---'---'---'---'---'---'--- e 1 ,-10.03, -9.08, -9.61, -9.57,-10.77, -9.89,-10.15, -9.87 SUMMARY STATISTICS Fleet Pred. ,SE(q),Partial,Raised, SLOPE SE ,INTRCPT, SE q FF Slope , ,Intrcpt ---' ,---,---,---,------,---,--- -9.87 , 0.520,0.0044 ,0.0044, O.OOOE+OO, O.OOOE+OO, -9.872, 0.173 Fbar SIGMA(int.) SIGMA(ext.) SIGMA(overall) Variance ratio 0.004 0.520 0.000 0.520 0.000 Age 2 Fleet, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991 ---'---'---'---'---'---'---'---'--- 1 , -8.12, -7.25, -7.33, -7.12, -7.44, -7.13, -7.69, -7.44 SUMMARY STATISTICS Fleet Pred. , SE(q),Partial,Raised, SLOPE SE ,INTRCPT, SE q FF Slope , ,Intrcpt ---,---,---,--_._------,---,--- 1 -7.44 ,0.350,0.0505 ,0.0505, O.OOOE+OO, O.OOOE+OO, -7.440, 0.117 Fbar SIGMA(int.) SIGMA(ext.) SIGMA(overall) Variance ratio 0.051 0.350 0.000 0.350 0.000 61 • Table 3.4.9 Virtual Population Analysis. Fishing mortality at age. Pandalus borealis in Fladen Ground (IVa). Run title Pandalus FLADEN Assessment Traditional vpa Terminal Fs estimated using Laurec/Shepherd method Table 8 Fishing rnortality CF) at age YEAR 1984 1985 1986 1987 1988 1989 1990 1991 FBAR 86-90 AGE 1 0.0680 0.1137 0.0741 0.1276 0.0086 0.0388 0.0155 0.0044 0.0529 2 0.4608 0.7125 0.7256 1.4787 0.2389 0.6113" 0.1824 0.0505 0.6474 3 0.4608 0.7125 0.7256 1.4787 0.2389 0.6113 0.1824 0.0505 0.6474 +gp 0.4608 0.7125 0.7256 1.4787 0.2389 0.6113 0.1824 0.0505 FBAR 1- 3 0.3299 0.5129 0.5085 1.0283 0.1621 0.4205 0.1268 0.0352 Table 3.4.10 Virtual Population Analysis. Stock number, total and spawning biomass. Pandalus borealis in Fladen Ground (IVa). Run title Pandalus FLADEN Assessment Traditional vpa Terminal Fs estimated using Laurec/Shepherd method Table 10 Stock number at age (start of year) Numbers*10**- 6 YEAR 1984 1985 1986 1987 1988 1989 1990 1991 1992 AGE 1 7466 5164 7901 7057 2953 12677 4416 3573 0 2 2464 2566 1695 2699 2285 1077 4486 1600 1309 3 1181 572 463 302 226 662 215 1375 559 +gp 0 0 0 0 0 0 0 0 481 TOTAL 11111 8301 10059 10057 5464 14416 9117 6547 2349 TOTALBIO 24 20 22 23 14 37 26 20 '000 tonnes TOTSPBIO 8 4 4 3 4 4 9 9 '000 tannes 62 Iable 3.5.1 Landings (t) of Pandalus borealis from Division IVb, the Farn Deeps as estimated by the Working Group. Year UK (England) UK (Scotland) Denmark Iotal CPUE kg/hr (Scotland) 1977 227 No data 1978 91 2 No data 1979 235 34 No data 1980 203 17 60 1981 1 1982 1983 6S 1984 30 1985 2 6 70 1986 137 57 106 300 127 1987 212 86 92 390 101 1988 91 25 384 500 67 1989 168 8 72 248 44 1990 144 + 1 145 No data 1991 3 3 11 • • 63 Table 4.3.1 Firth of Forth (FU 8) Males. Tuning output. Note: AL AL = Fleet used for tuning (see Table 5.1.4). Slope of 0 indicates Q is fixed. Age 2 Fl eet F var(F) wt slope int N AL AL .3349 .1723E+00 1.0000 .OOOOE+OO -.5487E+01 10· Hist F Not used Tuned F= .3349 Age 3 Fleet F var(F) wt slope int N AL AL .8021 .3385E-01 1.0000 .OOOOE+OO -.4614E+01 10 Hist F Not used Tuned F= .8021 Age 4 Fleet F var(F) wt slope int N AL Al .9862 .1616E-01 1.0000 .OOOOE+OO -.4408E+01 10 Hist F Not used • Tuned F= .9862 Age 5 Fleet F var(F) wt slope int N AL AL 1.0524 .1289E-01 1.0000 .OOOOE+OO -.4343E+01 10 Hist F Not used Tuned F=1.0524 Age 6 Fleet F var(F) wt slope int N AL AL 1.0650 .1468E-01 1.0000 .OOOOE+OO -.4331E+01 10 Hist F Not used Tuned F=1.0650 • Age 7 Fleet F var(F) wt slope int N AL AL 1.0548 .2183E-01 1.0000 .OOOOE+OO -.4340E+01 10 Hist F Not used Tuned F=1.0548 Age 8 Fleet F var(F) wt slope int N AL AL .9570 .7920E-01 1.0000 .OOOOE+OO -.4438E+01 10 Hist F Not used Tuned F= .9570 64 Table 4.3.2 Flrth of Forth (FU 8) Females. Tuning output. Note: AL AL = Fleet used for tuning (see Iable 5.1.4). Slope of 0 indicates Q is fixed. Age 2 Fleet var(F) wt slope int N AL AL .0439 .4323E+00 1.0000 .OOOOE+OO -.7519E+Ol 10 Hist F Not used Tuned F= .0439 Age 3 Fleet var(F) wt slope int AL AL .1068 .3803E+00 1.0000 .OOOOE+OO - .6630E+Ol 10 Hist F Not used Tuned F= .1068 • Age 4 Fleet var(F) wt slope int AL AL .1704 .2128E+00 1.0000 .OOOOE+OO ••6163E+Ol 10 Hist F Not used Tuned F= .1704 Age 5 Fleet var(f) wt slope int AL AL .1978 •1364E+00 1.0000 .OOOOE+OO - .6014E+Ol 10 Hist F Not used Tuned F= .1978 Age 6 Age 10 Fleet var(F) wt slope int N Fleet var(f) wt slope int N AL AL .2172 .8188E-Ol 1.0000 .OOOOE+OO - .5920E+Ol 10 AL AL .2259 .2056E+00 1.0000 .OOOOE+OO ••5881E+Ol 10 Hist F Not used Hist F Not used Tuned F= .2172 Tuned F= .2259 • Age 7 Age 11 Fleet var(F) wt slope int Fleet var(F) wt slope int N AL AL .2372 .8001E-01 1.0000 .OOOOE+OO ••5832E+Ol 10 Al Al .2539 •1988E+00 1.0000 .OOOOE+OO ·.5764E+Ol 10 Hist F Not used Hist F Not used Tuned F= .2372 Tuned F= .2539 Age 8 Age 12 Fleet var(f) wt slope int N Fleet var(F) wt slope int N Al Al .2503 .1049E+00 1.0000 .OOOOE+OO ••5779E+Ol 10 AL AL .2446 .2186E+00 1.0000 .OOOOE+OO ·.5802E+01 10 Hist F Not used Hist F Not used Tuned F= .2503 Tuned F= .2446 Age 9 Ag. 13 Fleet var(F) wt stope int Fleet var(F) wt slope int N Al Al .2503 .1520E+00 1.0000 .OOOOE+OO - .5778E+01 10 AL AL .2229 .1765E+00 1.0000 .OOOOE+OO ••5895E+Ol 10 Hist F Not used Hist F Not used Tuned F= .2503 Tuned F' .2229 65 Table 4.3.3 Moray Firth (FU 9) Males. Tuning output. Note: AL AL = Fleet used for tuning (see Table 5.1.4). Slope of 0 indicates Q is fixed. Age 2 Fleet F var(F) wt slope int N AL AL .1551 •2897E+00 .5752 .OOOOE+OO -.5881E+01 11 Hist F .1598 .3922E+00 .4248 .OOOOE+OO -.1834E+01 11 Tuned F= .1571 Age 3 Fleet F v~r(F) wt slope int N AL AL .3982 .8507E-01 .6447 .OOOOE+OO -.4938E+01 11 Hist F .4103 .1544E+00 .3553 .OOOOE+OO -.8909E+00 11 Tuned F= .4025 Age 4 Fleet F var(F) wt slope int N AL AL .5964 .6332E-01 .5381 .OOOOE+OO -.4535E+01 11 Hist F .6144 .7376E-01 .4619 .OOOOE+OO -.4871E+00 11 Tuned F= .6046 Age 5 Fleet F var(F) wt slope int N AL AL .7276 .7080E-01 .5765 .OOOOE+OO -.4336E+01 11 Hist F .7496 .9639E-01 .4235 .OOOOE+OO -.2882E+00 11 Tuned F= .7368 Age 6 Fleet F var(F) wt slope int N AL AL .8203 .1151E+00 .4699 .OOOOE+OO -.4216E+01 11 Hist F .8452 .1020E+00 .5301 .OOOOE+OO -.1682E+00 11 • Tuned F= .8334 Age 7 Fleet F var(f) wt slope int N AL AL .7237 .1741E+00 .4334 .OOOOE+OO -.4341E+01 11 Hist F .7456 .1332E+00 .5666 .OOOOE+OO -.2935E+00 11 Tuned F= .7360 66 Table 4.3.4 S~ and S Portugal (FU 28&29) Males. Tuning output. Note: AL AL = Fleet used for tuning (see Table 5.1.4). Slope of 0 indicates Q is fixed. Age I Fleet var(F) wt slope int AL AL .0569 .3560E+00 .5429 .OOOOE+OO -.7025E+Ol 7 Hist F .0667 .4228E+00 .4571 .OOOOE+OO - .2707E+Ol 7 Tuned F= .0612 Age 2 Fleet var(F) wt slope fnt N AL AL .3466 .3748E-Ol .7152 .OOOOE+OO - .5218E+Ol 7 Hi st F .4062 .9413E-Ol .2848 .OOOOE+OO - .9008E+00 7 Tuned F= .3627 Age 3 • Fleet var(F) wt slope fnt N AL AL .4448 .3804E-Ol .6002 .OOOOE+OO - .4969E+Ol 7 Hist F .5213 .5711E-Ol .3998 .OOOOE+OO -.6515E+00 7 Tuned F= .4739 Age 4 Fleet var(F) wt slope int AL AL .5586 .1819E+00 .3961 .OOOOE+OO -.4741E+Ol 7 Hist F .6546 .1193E+00 .6039 .OOOOE+OO - .4237E+OO 7 Tuned F= .6147 Age 5 Fleet var(F) wt slope int AL AL .5299 • 1766E+OO .2735 .OOOOE+OO - .4794E+Ol 7 Hist F .6210 .6651E-Ol .7265 .OOOOE+OO - .4764E+00 7 Tuned F= .5946 • Age 6 Fleet var(F) wt slope int AL AL .5253 .2104E+00 .3603 .OOOOE+OO - .4803E+Ol 7 Hist F .6156 •I 185E+00 .6397 .OOOOE+OO - .4851E+00 7 Tuned F= .5814 Age 7 Fleet var(F) wt slope int AL AL .7500 • 1685E+00 .2999 .OOOOE+OO ••4447E+Ol 7 Hist F .8790 .7216E-Ol .7001 .OOOOE+OO -.1290E+00 7 Tuned F= .8382 Age 8 Fleet var(F) wt slope fnt AL AL .8585 .4924E+00 .3520 .OOOOE+OO -.4311E+Ol 7 Hi st F 1.0061 .2675E+00 .6480 .OOOOE+OO .6102E-02 7 Tuned F= .9515 67 Table 4.3.5 SW and S Portugal (FU 28&29) Females. Tuning output. Note: AL AL = Fleet used for tuning (see Table 5.1.4). Slope of 0 indicates Q is fixed. Age 1 Fleet var(F) wt stape int AL AL .1024 .3946E+00 .5366 .OOOOE+OO -.6437E+Ol 7 H;st F' .1200 .4570E+00 .4634 .OOOOE+OO -.2120E+Ol 7 Tuned F= .1102 Age 2 Fleet var(F) wt stape int AL AL .1401 .2764E+00 .5440 .OOOOE+OO -.6124E+01 7 Hist F .1642 .3298E+OO .4560 .OOOOE-OO -.1806E+Ol 7 Tuned F= .1507 Age 3 Fleet var(F) wt stape int AL AL .1875 .1713E+00 .3366 .OOOOE-OO - .5833E+Ol 7 H;st F .2198 .8694E-Ol .6634 .OOOOE-OO -.1515E+Ol 7 • Tuned F= .2083 Age 4 Fleet var(F) wt stape int AL AL .2799 • 1479E+00 .3243 .OOOOE+OO -.5432E+Ol 7 Hist F .3280 .7098E·Ol .6757 .OOOOE+OO -.1115E+Ol 7 Tuned F= .3115 Age 5 Fleet var(F) wt stape int N AL AL .3729 •2726E+00 .2930 .OOOOE+OO -.5145E-Ol 7 Hist F .4370 .1130E+00 .7070 .OOOOE+OO ·.8278E-00 7 Tuned F= .4172 Age 6 Fleet var( F) wt stape int N AL AL .3644 .1698E+00 .3732 .OOOOE+OO - .5169E+Ol 7 • H;st F .4270 .1011E+00 .6268 .OOOOE-OO -.8510E+00 7 Tuned F= .4025 Age 7 Fleet var(F) wt stape int . ~ .. {" ".! . AL AL .4214 .2251E+0..D;,.,48?9. rOOOOE+OO .•.•S023E+Ol ., H;st F .4939 .2102E~~.o~ .51h'l{ ..MOOE+OO -.70~4E~00' 7 Tuned F= .4575 Age 8 Fleet var(F) wt stape int N AL AL .2996 .1996E+OO .4816 .OOOOE+OO -.5364E-Ol 7 Hist F .3511 .1855E-00 .5184 .OOOOE+OO -.1047E-Ol 7 Tuned F= .3253 68 Table 4.3.6 Firth Forth (FU 8) Males. Short term prediction input. Nephrops Short Term Prediction (Annual) 1992 wg (enter) Most Recent Oata yr (enter) 1991 Age 1 Recruits 1992 136973 Prop F before spawning .5 First Pred. Year 1992 Age 1 Recruits 1993 136973 Prop Mbefore spawning .5 Second 11 1993 Age 1 Recruits 1994 136973 Third 11 1994 recruits age 2 90511 Basic Input data (enter) Mean \/t Mean \/t Age M mat. catch 9 stock. 9 1 .3 1 6 6 2 .3 1 12 12 3 .3 1 21 21 4 .3 1 33 33 5 .3 1 48 48 6 .3 1 63 63 7 .3 1 79 79 8 .3 1 94 94 9 .3 1 105 105 10 .3 1 123 123 11 .3 1 142 142 • Stock size Fishing Fishing for pred pattern pattern Stock size mean F scaled to Jan 1 F Jan 1 81-90 1991 1991 1991 1992 ref F (enter) (enter) (overwrite (enter) Age with recruits) 1 10931 .2 136973 .076 .0848867 2 98822 .3349 90511 .283 .3160914 3 4n21 .8021 52374.52 .683 .7628638 4 12730 .9862 15851.62 .868 .9694960 5 2897 1.0524 3517.538 .933 1.042097 6 697 1.065 749.2188 .974 1.087891 7 186 1.0548 178.0003 .946 1.056617 8 61 .957 47.98n9 .894 .9985362 9 35 .3 17.35488 .941 1.051032 10 3 .n06 19.20841 .927 1.035395 11 3 .n06 2.056817 .927 1.035395 • Ref F .98625 mean .883 69 Tahle 4.3.7 Firth Forth (FU 8) Females. Short term prediction input. Nephrops Short Term Prediction (Annual) 1992 wg (enter) Most Recent Data yr (enter) 1991 Age Recrui ts 1992 147944 Prop F before spawning First Pred. Year 1992 Age Recruits 1993 147944 Prop Mbefore spawning Second 11 1993 Age Recruits 1994 147944 Third " 1994 recruits age 2 98861 Basic Input data (enter) Mean Ut Mean Ut Age M mat. catch 9 stock 9 1 .3 o 5 5 2 .2 1 7 7 3 .2 1 8 8 4 .2 1 10 10 5 .2 1 12 12 6 .2 1 15 15 7 .2 1 17 17 8 .2 1 19 19 9 .2 1 21 21 10 .2 1 25 25 11 .2 1 26 26 • 12 .2 1 28 28 13 .2 1 31 31 14 .2 1 33 33 15 .2 1 36 36 16 .2 1 44 44 Stock size Fishing Fishing for pred pattern pattern Stock size mean F scaled to Jan 1 Jan 1 81-90 1991 1991 1991 1992 ref F (enter) (enter) (overwrite (enter) Age with recruits) 1 17845 .2 147944 .055 .0582568 2 150564 .0439 98861 .041 .0434278 3 95223 .1068 117976.8 .095 .1006254 4 54081 •1704 70064.87 .146 .1546453 5 32973 .1978 37340.66 .169 .1790072 6 22247 .2172 22151.14 .187 .1980731 • 7 13879 .2372 14658.31 .208 .2203166 8 8888 .2503 8963.645 .225 .2383232 9 6089 .2503 5665.539 .235 .2489154 10 3414 .2259 3881.353 .22 .2330272 11 2370 .2539 2229.962 .25 .2648036 12 1594 .2446 1505.297 .25 .2648036 13 1189 .2229 1021.883 .226 .2393824 14 1107 .2 n8.9664 .273 .2891655 15 653 .224 742.0443 .249 .2637444 16 2221 .224 1880.814 .249 .2637444 Ref F .1966167. mean .185625 70 Table 4.4: 1 Ieeland males. Original slicing to create "age groups" far input to age based cohort analysis (data from Eirfksson)979 (1976». Length Removals Number Time Cumu- "Age" "Age" Mean interval 1000s at length interval lative groups groups length C 1000s dt dt (slicing) (for VPA) of "age" group 0-12 (0-1) 13-18 37036 0.938 0.938 1 (2) 19-24 80 33524 1.035 1.973 2 3 21.5 25-29 573 24994 0.953 2.926 3 4 27.0 30-34 1846 21432 1.055 3.981 4 5 32.0 35-38 2046 13869 0.933 4.914 5 6 36.5 39-42 2005 10696 1.030 5.944 6 7 40.5 43-46 1671 7723 1.153 7.097 7 8 44.5 47-49 973 4087 0.959 8.056 8 9 48.0 50-52 830 2843 1.065 9.121 9 10 51.0 53-55 554 1823 1.195 10.316 10 11 54.0 56-57 266 777 0.879 11.195 11 12 56.5 58-59 218 500 0.971 12.166 12 13 58.5 • 60-61 122 293 1.076 13.242 13 14 60.5 62-63 84 155 1.230 14.472 14 15 62.5 64+ 58 80 1.460+ 15.932+ 15+ 16+ 64.5+ Table 4.4.2 Tag-recapture results of Nephrops at Ieeland (Eirfksson, 1982b) No. Carapace length (mrn) Months Incrernent % growth at tagging at recapture . in sea (mrn) per year 1 35 38 9 3 11.4 2 35 38 20 3 5.1 • 3 39 42 10 3 9.2 4 40 46 9 6 20.0 5 41 44 10 3 8.8 6 43 46 11 3 7.7 7 43 45 9 2 6.3 8 45 48 9 3 8.9 9 47 50 9 3 7.7 10 50 56 20 6 7.2 11 52 57 24 5 4.8 12 63 65 10 2 3.8 Mean 44.4 47.8 12.5 3.5 8.4 71 Table 4.4.3 Nephrops. Landings in numbers byage (millions) in the )'cars 1971-1991. Age 1971 1972 1973 1974 1975 1976 1977 3 0.274 0.742 0.796 0.085 0.490 0.189 0.264 4 3.201 4.440 3.417 1.068 3.201 2.213 3.270 5 10.197 14.744 8.605 4.163 9.642 6.782 10.044 6 11.386 15.581 9.627 4.524 8.850 10.041 10.549 7 11.863 14.659 9.416 4.970 7.276 10.199 10.216 8 10.924 11.727 7.854 4.944 6.521 8.180 8.524 9 8.397 7.338 4.800 3.284 4.135 4.757 4.888 10 6.981 5.854 3.502 3.030 3.240 3.616 3.814 11 5.932 4.613 2.502 2.779 2.493 2.597 2.329 12 3.201 2.138 1.391 1.311 1.133 1.330 1.130 13 2.488 1.672 1.1 16 0.895 0.906 0.862 0.895 14 1.456 1.208 0.580 0.599 0.594 0.584 0.557 15 0.735 0.672 0.619 0.319 0.326 0.526 0.367 16 0.831 0.569 0.692 0.461 0.421 0.463 0.235 Age 1978 1979 1980 1981 1982 1983 1984 3 0.126 0.007 0.050 0.055 0.081 0.098 0.107 4 1.545 0.242 0.542 0.693 0.997 0.648 0.871 5 7.109 1.960 3.413 3.108 5.555 3.887 4.116 6 8.290 4.344 6.055 5.600 6.408 6.039 5.648 7 7.677 5.434 8.473 7.555 7.621 6.087 6.539 8 6.555 4.960 8.906 8.689 8.203 6.711 6.042 9 4.019 3.039 5.335 5.943 5.878 4.788 4.049 10 2.729 2.378 4.006 4.665 4.713 5.200 3.434 • 11 1.793 1.390 2.499 3.152 3.590 4.073 3.262 12 0.651 0.529 0.932 1.139 1.258 1.867 1.572 13 0.462 0.390 0.564 0.603 0.951 1.190 1.342 14 0.278 0.172 0.260 0.359 0.326 0.635 0.788 15 0.190 0.091 0.142 0.116 0.151 0.374 0.444 16 0.293 0.053 0.096 0.074 0.099 0.230 0.493 Age 1985 1986 1987 1988 1989 1990 1991 3 0.032 0.040 0.042 0.093 0.071 0.087 0.047 4 0.805 0.780 0.336 0.730 0.945 1.131 0.992 5 3.587 3.928 2.369 2.647 3.923 5.679 5.058 6 5.160 6.662 5.098 4.385 4.141 7.458 8.176 7 6.030 8.496 6.988 5.856 4.692 5.854 9.162 8 6.709 7.322 8.150 5.988 5.021 4.416 7.051 9 5.138 4.943 5.435 5.189 3.540 2.698 3.992 10 3.999 4.012 4.497 4.020 3.028 2.122 2.779 11 3.205 3.103 3.451 2.528 2.621 1.574 1.862 12 1.309 1.194 1.583 1.200 1.211 0.813 0.799 13 0.952 0.896 1.143 0.858 0.792 0.642 0.619 14 0.545 0.514 0.597 0.469 0.513 0.413 0.353 15 0.297 0.232 0.412 0.345 0.360 0.334 0.258 • 16 0.208 0.142 0.388 0.211 0.268 0.312 0.209 72 Table 4.4.4 Nephrops. Fishin~ Il\ortality hy a~e in the year<; 1971-199I. Age 1971 1972 1973 1974 1975 1976 1977 3 0.002 0.005 0.005 0.001 0.003 0.001 0.002 4 0.029 0.040 0.029 0.009 0.024 0.016 0.025 5 0.118 0.179 0.101 0.045 0.099 0.064 0.096 6 0.171 0.264 0.170 0.071 0.127 0.142 0.133 7 0.240 0.347 0.253 0.125 0.155 0.212 0.210 8 0.325 0.395 0.317 0.204 0.238 0.261 0.275 9 0.317 0.379 0.278 0.212 0.263 0.274 0.246 10 0.397 0.381 0.313 0.284 0.334 0.387 0.369 11 0.466 0.499 0.278 0.439 0.399 0.489 0..163 12 0.342 0.304 0.273 0.230 0.322 0.385 0.409 13 0.308 0.301 0.257 0.283 0.246 0.434 0.486 14 0.203 0.241 0.162 0.213 0.309 0.248 0.558 15 0.194 0.136 0.187 0.126 0.172 0.494 0.244 16 0.235 0.226 0.202 0.207 0.242 0.392 0.429 Age 1978 1979 1980 1981 1982 1933 1984 3 0.001 0.000 0.000 0.000 0.001 0.001 0.001 4 0.014 0.002 0.005 0.007 omo 0.007 0.010 5 0.070 0.021 0.040 0.038 0.069 0.050 0.056 6 0.106 0.056 0.085 0.085 0.102 0.100 0.095 7 0.135 0.094 0.147 0.145 0.159 0.134 0.150 8 0.202 0.121 0.220 0.221 0.231 0.205 0.190 9 0.202 0.136 0.186 0.224 0.228 0.205 0.183 • 10 0.211 0.176 0.266 0.245 0.278 0.324 0.222 11 0.296 0.158 0.284 0.346 0.303 0.412 0.347 12 0.226 0.133 0.151 0.202 0.226 0.254 0.276 13 0.292 0.205 0.205 0.138 0.259 0.346 0.293 14 0.272 0.168 0.205 0.194 0.103 0.275 0..106 15 0.375 0.134 0.203 0.132 0.117 0.164 0.315 16 0.313 0.169 0.204 0.155 0.159 0.262 0.338 Age 1985 1986 1987 1988 1989 1990 1991 3 0.000 0.000 0.000 0.001 0.000 0.001 0.000 4 0.010 0.009 0.003 0.005 0.006 0.010 0.009 5 0.052 0.062 0.035 0.032 0.034 0.048 0.055 6 0.092 0.128 0.106 0.084 0.064 0.084 0.090 7 0.139 0.216 0.193 0.170 0.122 0.121 0.140 8 0.226 0.249 0.331 0.251 0.216 0.162 0.210 9 0.245 0.260 0.296 0.364 0.231 0.173 0.215 10 0.277 0.308 0.398 0.373 0.375 0.211 0.270 11 0.332 0.360 0.474 0.409 0.445 0.341 0.290 12 0.228 0.198 0.315 0.298 0.351 0.240 0.290 13 0.268 0.241 0.295 0.282 0.329 0.318 0.290 14 0.186 0.226 0.250 0.189 0.271 0.285 0.290 • 15 0.263 0.112 0.285 0.224 0.217 0.285 0.290 16 0.239 0.193 0.277 0.232 0.272 0.296 0.290 73 Tablc 4.4.5 Nephrops. Stock auundant'e in numucrs U)' age (millions) and lishable stock in thousand tonnes in the years 1971-1991. Age 1971 1972 1973 1974 1975 1976 1977 3 153.602 160.762 170.347 185.401 184.741 176.763 155.208 4 124.281 125.511 130.951 138.750 151.717 150.811 144.551 5 101.194 98.863 98.751 104.128 112.634 121.325 121.475 6 79.489 73.658 67.663 73.091 81.495 83.521 93.212 7 61.153 54.824 46.293 46.726 55.760 58.745 59.332 8 43.155 39.395 31.720 29.431 33.776 39.097 38.916 9 33.933 25.518 21.729 18.913 19.645 21.786 24.652 10 23.352 20.237 14.305 13.474 12.528 12.365 13.559 11 17.443 12.854 11.314 8.565 8.308 7.347 6.878 12 12.131 8.963 6.391 7.013 4.520 4.565 3.688 13 10300 7.057 5.417 3.982 4.562 2.683 3.688 14 8.715 6.197 4.275 3.431 2.455 2.920 1.423 15 4.584 5.824 3.987 2.978 2.270 1.476 1.865 16 4.360 3.091 4.163 2.707 2.150 1.565 0.737 Fishable stock 6+ 20.800 16.800 13.900 12.700 13.000 13.200 13.400 Age 1978 1979 1980 1981 1982 1983 1984 3 144.374 137.894 137.182 133.036 125.180 118.140 109.405 4 126.835 118.089 112.892 112.270 108.871 102.416 96.636 5 115.395 102.449 96.465 91.938 91.293 88.235 83.266 6 90.397 88.064 82.108 75.898 72.467 69.732 68.733 7 66.808 66.535 68.180 61.762 57.088 53.552 51.646 • 8 39.381 47.778 49.573 48.186 43.758 39.874 38.359 9 24.197 26.341 34.646 32.571 31.631 28.445 26.604 10 15.786 16.192 18.827 23.561 21.319 20.608 18.978 11 7.677 10.468 11.115 11.812 15.094 13.217 12.200 12 3.544 4.674 7.318 6.854 6.840 9.131 7.167 13 2.006 2.315 3.350 5.152 4.586 4.468 5.796 14 1.280 1.227 1.545 2.235 3.674 2.899 2.589 15 0.667 0.798 0.849 1.031 1.506 2.714 1.803 16 1.197 0.375 0.572 0.568 0.739 1.097 1.885 Fishable stock 6+ 13.700 14.700 16.100 16.200 15.900 15.300 14.600 Age 1985 1986 1987 1988 1989 1990 1991 1992 3 113.848 138.787 194.182 201.609 156.756 149.445 153.000 153.000 4 89.477 93.182 113.593 158.945 164.979 128.277 122.277 125.000 5 78.332 72.530 75.586 92.699 129.474 134.220 104.003 99.216 6 64.457 60.896 55.838 59.746 73.505 102.462 104.764 80.585 7 51.180 48.119 43.852 41.119 44.960 56.444 77.161 78.399 8 36.392 36.468 31.750 29.611 28.391 32.581 40.935 54.917 9 25.965 23.758 23.270 18.672 18.857 18.725 22.696 27.168 10 18.135 16.636 15.005 14.167 10.629 12.253 12.901 14.989 11 12.447 11.252 10.014 8.250 7.990 5.984 8.122 8.063 12 7.059 7.312 • 6.426 5.106 4.486 4.191 3.485 4.976 13 4.454 4.601 4.911 3.839 3.102 2.585 2.700 2.135 14 3.539 2.790 2.961 2.994 2.371 1.828 1.540 1.654 15 1.413 2.407 1.822 1.887 2.029 1.480 1.125 0.943 16 1.077 0.889 1.761 1.121 1.235 1.337 0.912 0.689 Fishable stock 6+ 13.900 13.300 12.400 11.300 11.300 12.700 14.600 15.200 74 .------ Table 4.4.6 Projection of fishable stock biomass (6+ in thous. tonnes) in 1993-1994, far different management strategies in 1992. 1992 1992 1993 1994 Fishable stock Fishable stock Fishable stock biomass F _ Catch biomass biomass 6 13 15.2 0.22 = Fa.! 2.3 15.5 15.6 0.44 = F 4.2 13.4 12.0 • max • 75 Table 4.4. 7 VPA. SE Ieeland (Functional Unit 1): Males Catch (OOO's) at 'nominal age' . 1981 - 1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 173. 269. 253. 28L 22L 443. 255. 52L 636. 847. 470. 2 1405. 1830. 1706. 1559. 1122. 2415. 1593. 1082. 2797. 4661. 2818. 3 3208. 2997. 3512. 3088. 2223. 4890. 3741. 2008. 2795. 6508. 6162. 4 4149. 393L 3202. 3566. 3010. 5716. 4449. 1915. 2526. 4241. 6793. 5 4298. 3903. 2803. 2713. 3223. 4488. 4087. 1545. 1986. 2610. 4143. 6 3588. 3642. 2589. 2034. 2833. 3271. 3083. 1282. 1624. 1686. 2652. 7 2605. 2800. 2498. 1629. 1842. 2150. 2319. 95L 1283. 1312. 162L 8 1456. 1720. 1642. 1282. 1155. 1287. 1434. 619. 76L 723. 822. 9 706. 838. 1202. 1029. 753. 709. 956. 438. 552. 579. 520. 10 266. 392. 624. 702. 417. 431- 478. 181. 324. 346. 336 • 11 198. 192. 487. 816. 414. 21L 445. 18L 343. 44L 262. • Table 4.4. 8 VPA. SE Ieeland (Functional Unit 1): Males Mean weight (kg) at 'nominal age'. 1981 - 1991 1986 1987 1988 1989 1990 1991 Age 1981 1982 1983 1984 1985 .0160 .0160 .0170 1 .0170 .0160 .0160 .0160 .0160 •0170 .0150 .0150 .0260 .0260 .0250 .0260 .0260 2 .0260 .0260 .0260 .0260 .0260 .0260 • .0370 .0370 .0370 .0370 .0370 3 .0370 .0370 .0370 .0370 .0370 .0370 .0510 .0510 .0510 .0500 .0500 4 .0510 .0510 .0510 .0510 .0510 .0510 .0650 .0660 .0660 .0650 .0650 5 .0660 .0660 .0660 .0650 .0660 .0650 .0800 .0800 .0800 6 .0810 .0810 .0810 .0810 .0800 .0800 .0800 .0800 .0970 .0970 .0970 .0970 7 .0970 .0970 .0970 .0970 .0970 .0970 .0970 .1120 .1120 .1130 .1120 8 .1120 .1120 .1130 .1120 .1120 .1120 .1120 .1280 .1280 .1280 .1280 9 .1270 .1280 .1280 .1280 .1280 .1280 .1280 .1420 .1430 .1430 .1420 10 .1440 .1420 .1420 .1430 .1430 .1430 .1420 .1620 .1630 .1650 .1640 11 .1610 .1620 .1640 .1650 .1640 .1650 .1640 76 1): Males Table 4.4. 9 VPA. SE Iceland (Functional Uni t Fishing mortality (F) at 'nominal agc' . 1981 - 1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0033 .0054 .0055 .0066 .0053 .0096 .0043 .0060 .0073 .0022 .0010 2 .0304 .0436 .0426 .0424 .0328 .0740 .0431 .0227 .0403 .0681 .0090 3 .0956 .0839 .1102 .1010 .0783 .1947 .1569 .0701 .0753 .1240 .1206 4 .1688 .1624 .1212 .1560 .1352 .2942 .2725 .1124 .1182 .1564 .1841 5 .2085 .2370 .1667 .1430 .2060 .3049 .3544 .1428 .1631 .1723 .2252 6 .2784 .2740 .2442 .1753 .2180 .3326 .3552 .1785 .2194 .2028 .2653 7 .2446 .3647 .3064 .2391 .2378 .2558 .4173 .1756 .2723 .2767 .3060 8 .1767 .2528 .3783 .2549 .2661 .2601 .2709 .1857 .2076 .2428 .2795 9 .2042 .1461 .2816 .4335 .2336 .2595 .3139 .1237 .2509 .2415 .2760 10 .2271 .1672 .1545 .2640 .3136 .2035 .2796 .0894 .1266 .2464 .2151 11 .2085 .2546 .3221 .3092 .2459 .2585 .3341 .1617 .2436 .2537 .2985 ~ Table 4.4.10 VPA. SE Iceland (Functional Uni t 1): Males Population numbers (OOO's) at 'nominal age'. 1981 - 1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 57949. 55428. 50911. 47180. 45795. 51382. 65092. 96004. 96040. 424786. 518264. 2 51675. 47289. 45137. 41453. 38373. 37294. 41667. 53062. 78130. 78055. 347019. 3 38776. 41037. 37065. 35412. 32528. 30402. 28355. 32677. 42465. 61436. 59700. 4 29393. 28854. 30895. 27179. 26209. 24626. 20488. 19844. 24942. 32245. 44433. 5 25112. 20327. 20082. 22408. 19039. 18745. 15024. 12m. 14520. 18143. 22579. 6 16216. 16691. 13130. 13917. 15901. 12686. 11313. 8630. 9066. 10099. 12503. 7 13192. 10050. 10390. 8421. 9562. 10469. 7448. 6493. 5911. 5960. 6751. 8 9890. 8458. 5714. 6262. 5428. 6172. 6637. 4017. 4460. 3686. 3700. 9 4199. 6785. 5378. 3205. 3973. 3406. 3896. 4144. 2731. 2967. 2367. 10 1439. 2803. 4800. 3322. 1701. 2575. 2151. 2330. 2998. 1740. 1908. 11 1157. 939. 1941. 3367. 2089. 1018. 1720. 1332. 1745. 2163. 1114 • Table 4.4. 11 VPA. SE Iceland (Functional Unit 1): Males • Yield (tonnes),Fbar,Total stock biomass (tonnes),1981 - 1991 spawning stock biomass (tonnes), Ln recruitment Year, Yield, Fbar, 1SB, SSB, Log R 3-11 1981, 1519.6, .2014, 11547.6, 11547.6, 10.97 1982, 1574.2, .2159, 11140.6, 11140.6, 10.92 1983, 1486.5, .2317, 10666.0, 10666.0, 10.84 1984, 1350.6, .2307, 10071.9, 10071.9, 10.76 1985, 1239.8, .2149, 9429.2, 9429.2, 10.73 1986, 1636.1, .2626, 9136.2, 9136.2, 10.85 1987, 1571.7, .3061, 8587.4, 8587.4, 11.08 1988, 685.0, .1378, 8731.1, 8731.1, 11.47 1989, 955.8, .1863, 10152.3, 10152.3, 11.47 1990, 1297.5, .2130, 16678.8, 16678.8, 12.96 1991, 1536.8, .2412, 26557.3, 26557.3, 13.16 77 Table 5.1.1 - Nephrops Funct i onal Units and description by Statistical Rectangles No. Name ICES Oivision Statistical Rectangles 1 Ieeland - South coast Va 55-56 C6-00;55-56 02-D4 2 Faroe Islands Vb 53E3 3 Skagerrak lIla 47GO; 46F9-Gl; 45F8-Gl; 44F7-GO; 43F8-F9 4 North and Central Kattegat lIla 44Gl;42-43 GO-G2;41GI-G2 5 Botney Gut and Silver Pit IVb,c 36-37 FI-F4;35F2-F3 6 Farn Oeeps IVb 38-40 E8-E9;37E9 7 Fladen Ground IVa 44-49 E9-Fl;45-46E8;44-45F2 8 Firth of Forth IVb 40-41E7;41E6 9 Moray Firth IVb 44-45 E6-E7;44E8 10 Noup IVb 47E6 11 North Minch VIa 44-46 E3-E4 12 South Minch VIa 41-43 E3-E4;42E2 13 Clyde VIa 39-40 E4-E5 14 Irish Sea East VIla 35-38E6;38E5 15 Irish Sea West VIIa 35-37 E4-E5;38E4 16 Porcupine Bank VIlc,k 3406-08;3305-08;3205-06 17 Aran Islands VIlb 34-35 D9-EO 18 NW and W Ireland VIIb 3709-El;3609 • 19 SW Ireland VIlg, j 31-33 09-EO 20 NW Labadie, Baltimore and VIIg, j Galley 21 Jones and Cockburn VIlg,h,j } 28-32 EI-E2;31-33E3;31E4 22 Smalls VIIg 23 Bay of Biscay North VlIIa 22-24 E6-E7;23-24E5 24 Bay of Biscay South Vlllb 20-21 E7-E8;19E8 25 North Galicia VIllc 15EO-El;16El 26 West Galicia IXa 13-14 EO-E1 27 North Portugal North of IXa 6-12EO;9-12El Cape Espichel) 28 SW Portugal (Alentejo) IXa 3-5 EO-El 29 S Portugal (Algarve) IXa 2EO-E2 30 Gulf of Cadiz IXa 2-3 E2-E3 31 Cantabrian Sea VlIIc 16E4-E7 • 78 .------ Table 5.1.2 Deseription of Management Areas together with their Nephrops Working Group labels and the Funetional Units eontained within them Working Group Management Area Deseription Funetional Units Label I A Va 1 Ieeland B Vb (non EC) 2 Faroe Islands C VIa 11 North Mineh 12 South Mineh 13 Clyde D Vb (EC) + Vlb None E IIIa 3+4 Skagerrak and Kattegat F IVa: reet. 44-48 E6-E7 + 44E8 9 Moray Firth 10 Noup G IVa: remainder 7 Fladen 0 H IVb,e E of 1 E 5 Botney Gut 0 I IVb,e W of 1 E 6 Farn Deeps 8 Firth of Forth J VIIa: exeluding reet. 33 E2-E5 14 Irish Sea East 15 Irish Sea West K VIId,e None L VIIb,e,j,k 16 Poreupine Bank 17 Aran Grounds 18+19 Irish eoast • M Vllf,g,h and Vlla 33E2-E5 20+21+22 Celtie Sea N VlIIa,b 23+24 Bay of Biseay 0 VIIlc 25 North Galicia 31 Cantabrian Sea P VI IId, e None Q IXa 26 West Galieia 27 N Portugal 28+29 Sand SW Portugal 30 Gulf of Cadiz R IXb + X None 79 Iable 5.1.3 Input parameters used in assessments cf male and female Nephrops froffi various Functional Units. For some stocks, growth and natural mortality paraffieters are given for immature females(above) and mature females (below) ; TL = Transition length. MALES FEMALES r,------....'------.., r,------....,------, MA Functlonal Unit Ref. Grp. Dis. +Grp In.F K Loo M a b +Grp In.F K Loo M a b Period Int. Surv. TL A IceIand(1) 88-90 2 72 0.4 0.11 80 0.2 .00113 2.867 B Faroes (2) Not Assessed 0 16 0.1 1 . 66 25 C N.Minch Oll 80-90 7. 0.25 62 0.150.16366 0.3 .00028 3.24 54 0.030 0.06 58 0.2 .00084 7..91 iO.16 68 0.3 S.Mlnch (12) 85-90 2 0.25 64 0.3 0.161 68 0.3 .00029 3.24 56 0.025 '0.06 59 26 0.2 .00U89 2.91 1°.167327 0.3 F. Clyde (13) 88-90 2 0.25 68 0.2 0.16 73 0.3 .00028 3.24 59 0.025 0.06 62 0.2 .000845 2.91 D None E Skag/Katt(3.4) 1990 2 0.25 68 0.3 0.16 75 0.3 .00051 3.08 60 0.200 0.10 64 0.2 .0018 2.71 10.165 62 23 0.3 F Moray Firth (9) 85-90 2 0.25 58 0.050.165 62 0.3 .00028 3.24 52 0.025 0.06 56 0.2 .00074 2.91 Not.:p (0) Not Assessed 10.16 66 25 0.3 G Fladen (7) 86-90 2 0.25 62 0.20 0.16 66 0.3 .00030 3.25 52 0.1 0.10 56 0.2 .00074 2.91 11 flrtney Gut (5) 86-90 2 0.25 56 0.200.165 62 0.3 .00030 3.24 54 0.1 0.03 60 0.2 .00135 2.82 0 16 1 . 66 24 0.3 Farn Deeps (6) 84-90 2 0.25 60 0.200.16 66 0.3 .00033 3.17 54 0.03 0.06 58 0.2 .00091 2.89 0.163 66 25 0.3 Firth Forth (8) 81-90 2 0.25 61 0.100.16366 0.3 .00028 3.24 53 0.05 0.065 58 0.2 .00085 2.91 1°. 16 60 24 0.3 lrlsh Sea E (14)• 85-88 2 0.25 52 0.500.16 60 0.3 .00029 2.94 48 0.50 0.10 56 0.2 .00029 2.92 0 16 1 . 60 24 0.3 lrish Sea W (15) 87-90 2 0.10 54 0.2 0.16 60 0.3 .00032 3.21 52 0.10 0.10 56 0.2 .00068 2. ')6 K None I. POl c. Bank (16) 81-89 2 68 0.4 0.14 75 0.2 .00009 3.55 50 0.40 0.16 60 0.2 .00009 355 10 . 15 60 24 Aran Grounds(17) 1990 2 56 0.2 0.15 60 0.3 .00032 3.21 44 0.20 0.10 50 0.2 .00068 2.96 Irish Coast(18.19) Not Assessed 10 . 17 68 24 0.3 M Celt.Sea (20-22) 87-90 2 0.25 62 0.250.17 68 0.3 .00009 3.55 46 0.15 0.10 49 0.2 .00009 3.55. N Biscay (23.24) 87-89 2 0.30 64 0.5 0.11 76 0.3 .00039 3.18 54 0.40 0.14 56 0.3 .00081 2.97 o N.Galicia (25) 84-90 2 68 0.2 0.12 80 0.2 .00043 3.16 58 0.30 0.15 65 0.2 .00043 3.16 Cantabrian(31)• 88-90 5 75 0.2 0.15 90 0.2 .00043 3.16 60 0.10 0.10 70 0.2 .00043 3.16 P None Q.15 85 240 . 2 Q W.Gallcia (26) • 89-90 5 75 0.1 0.15 85 0.2 .00043 3.16 55 0.4 (1).10 70 0.2 .00043 3.16 JO.20 70 26 0.2 N.Porlugal(27) 85-90 2 64 0.2 0.20 70 0.2 .00028 3.22 60 0.1 10.068 65 0.1 .00056 3.03 JO.20 70 26 0.2 :;;; :; 1' • No ncw asscssmcnt, 1991 WG input parameters given. 80 ., . , Tahle 5.1.4 Input choices for slicing and for tuning of VPA FU5 FU6 FU7 FU8 FU9 FU11 FU12 FU13 FU15 FU16 FU20-22 FU23,24 FU25 FU27 FU28, 29 Years of Length data 86-91 84-91 80-91 81-91 80-91 80-91 80-91 80-91 84-91 81-91 84-90 84-91 84-91 85-91 84-91 Grouping interval 1 2 2 2 2 2 2 2 2 2 1 1 2 2 2 No. Ages Groups· male 13 11 8 11 9 11 11 11 11 11 8 9 10 7 10 female 16 15 13 16 16 14 14 14 12 - 10 10 11 10 10 2 eurves for fem.? N Y N Y Y Y YYY - Y N N Y Y (. ine. plus gp.) EH? Effort Units Hours Hours Hours Hours Hours Hours Hours Hours Hours Day·l00 Hours Hours Fdays Hours Hours Years for analysis 86-91 84-90 80-91 81-91 80-91 80-91 80-91 80-91 84-90 81-91 84-90 84-91 85-91 85-90 84-91 Tuning age range male 2-10 2-7 2-6 2-8 2-7 2-8 2-8 2-8 3-8 3-8 1-6 1-7 2-6 1-5 1-8 female 2-13 2-10 2-10 2-13 2-13 2-11 2-11 2-11 3-8 - 1-8 1-8 2-6 1-8 1-8 F Fixed on oldest? N N N NN NNNN N N NN N N No.ages for mean. 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 Downweighting exp. 0 0 3 3 3 3 3 3 3 3 0 0 0 0 0 Y rs. prior to last 0 2 2 2 2 2 2 2 2 2 0 0 2 0 0 for max.wt Multi-flcet •• YNY N NYY N YY Y N N NN Fleet names Bel. Y Eng. Y SeT. Y SeT. Y SeT. Y SeT. Y SeT. Y SeT. Y NI. Y Sp. Y Fr. Y Fr. Y Sp.Y Po.Y PO.Y and Fix Q (Y/N) Den. E Den. E SeC. E SeC. E I. E Fr. E 1. E o r exelude fleet E UK. E Ir. E Hist F (Y/N/E) E E E EY E YY Y(m)E(f) EY Y Y E Y Take Logs? Y YYY Y Y YY YY Y Y Y YY Age range FBAR males 2-10 3-7 3-6 3-8 3-7 3-8 3-8 3-8 3-8 3-8 2-6 2-7 2-6 2-6 3-8 females 2-13 3-10 3-8 3-10 3-10 3-11 3-11 3-11 3-8 - 2-8 2-7 2-6 3-8 3-8 FBAR vs effort male r 0.945 0.824 0.677 0.950 0.764 0.619 0.480 0.252 -0.35 0.003 0.794 0.346 0.629 0.542 0.4722 female r 0.898 0.783 0.831 0.710 0.786 0.281 0.733 0.481 0.72 - 0.416 0.557 0.110 0.595 0.1225 •• Bel. = Belgium Den. = Denmark SeT. = Seotland Trawl SeC. Creel NI. = Northcrn Ireland I. = Ireland Sp. = Spain Fr. = Franee Po. = Portugal Table 5.1.5 Regression parameters and correlation coefficients for the relationship between landings(t) and effort(t) and that between landings(t) and LPUE(t-l) for the Funetional Units regarded as having adequate effort data. Funetional Unit Landings(t) vs Effort(t) Landings(t) vs LPUE(t-l) r slope intereept r slope intereept 1 Ieeland 0.279 17.66 1472.73 0.828 37.16 561. 88 3 Skagerrak 0.801 6.46 82.50 0.693 82.95 -144.12 4 Kattegat 0.167 2.04 72.96 0.307 4.62 69.38 5 Botney Gut 0.234 1.37 452.59 0.296 9.96 427.00 6 Farn Deeps 0.869 19.02 327.00 -0.056 -7.79 2241. 40 7 Fladen Grund 0.972 36.75 -37.73 0.257 31.08 97.73 8 F. of Forth 0.911 27.24 -184.86 0.547 95.67 -616.99 9 Moray Firth 0.877 21. 39 488.57 -0.142 -10.26 1836.33 10 Noup 0.933 25.61 5.46 -0.234 -0.79 64.91 11 North Minch 0.540 18.07 1136.75 0.512 54.85 1114.09 12 South Mineh 0.814 14.51 1396.36 -0.056 -6.67 3239.66 13 F. of Clyde 0.606 24.47 -491. 19 0.373 77.25 1474.48 14 Irish Sea E 0.797 27.88 -27.31 0.722 21.26 -39.59 15 Irish Sea W 0.832 21.19 1407.68 -0.205 -43.57 6500.84 16 Pore. Bank (NT) 0.349 74.51 -75.06 0.974 8.01 4.32 (Fr) 0.919 39.89 -2478.25 0.665 74.74 181.53 20-22 Cel tie Sea 0.805 13.35 607.73 0.364 258.88 -183.76 23-24 Biscay 0.823 6.85 963.55 0.151 125.45 4125.35 25 N. Galieia 0.333 5.10 203.58 -0.036 -1.03 348.55 27 N. Portugal 0.726 4.33 0.67 0.031 0.28 44.17 28-29 S SW Port. 0.689 4.14 104.08 0.124 5.60 401.74 NT = Nephrops Trawl FT = Finfish Trawl • 82 Table 5.1.6 - Summary of Catch Options for each Management Area Listed Management Area Cateh Options (Tonnes) Text Seetion For Details A Va Managed by National TAC 5.2.2 B Vb (non EC) Managed by National TAC 5.3.2 C VIa 11575 11207 5.4.4 D Vb (EC) + Vlb Zero TAC 5.5.1 E lIla 4000 5.6.3 F IVa: reet. 44-48 E6-E7 + 44E8 2298 5.7.3 G IVa: remainder 4376 5.8.2 H IVb,c E of 1° E 920 5.9.2 I IVb,c Wof 1° E 4654 4268 5.10.3 J Vlla: excluding reet. 33 E2-E5 9306 5.11.3 K VIId,e Zero TAC 5.12.1 L VIIb,e,j,k 4056 5.13.4 M Vllf,g,h and Vlla 33E2-E5 3500 5.14.2 N VIIla,b 6887 5.15.2 o VlIIe 569 5.16.3 P VIIld,e Zero TAC 5.17.1 • Q IXa 1336 5.18.5 R IXb + X Zero TAC 5.19.1 83 Table 5.2.1- Ieeland (Functional Unit 1) : catches and lan dings (ln tonnes), effort (in '000 hours traw Ilng), CPUE and LPUE (ln kg/hour trawllng), of Icelandic Nephrops trawlers, TAC (in tonnes), 1982-91 Year Catches Landings Effort CPUE LPUE TAC 1982 2 889 2 603 50.5 57.2 51.5 2700 83 2 891 2 672 55.9 51. 7 47.8 2700 84 2 698 2 459 53.9 50.1 45.6 2400 85 2 628 2 385 42.3 62.1 56.4 2300 86 2 882 2 564 41. 8 68.9 61.3 2500 1987 2 980 2 712 51. 6 57.8 52.6 2700 88 2 496 2 240 56.1 44.5 39.9 2600 89 2 100 1 841 51.1 41.1 36.0 2100 90 1 939 1 660 41.5 46.7 40.0 2100 91 (.) NA 2 160 51.3 NA 42.1 2100 (.) provisional Table 5.2.2 Ieeland (Functional Unit 1) : Landings (in to- nnes), effort (in '000 creel hauls) and LPUE (ln g/creel haul),1989-1991 Year Landings Effort LPUE 1989 25 113.1 221 1990 31 103.0 301 1991 (.) 10 NA NA (.) provisional Table 5.2.3 Ieeland (Functional Unit 1) : mean slzes (CL in mm) of male and female Nephrops in catches, 1982-91 Year Males Females • 82 43.5 34.8 83 44.8 34.1 84 44.4 35.0 85 44.5 35.4 1986 43.7 35.6 87 45.5 37.2 88 44.7 36.5 89 44.0 35.7 90 41.6 35.6 91 (.) 42.1 35.6 (.) provisional 84 Table 5.3.1 Faroes (Functional Unit 2) : landings (in ton nes), effort (in '000 creeldays) and LPUE (in g/creelday), 1981-90 Season Landings Effort LPUE 1981/82 50 1 431 35 82/83 81 1 530 53 83/84 93 1 454 64 84/85 50 1 697 30 85/86 43 784 55 1986/87 80 822 97 87/88 91 934 97 88/89 74 960 77 89/90 (-) 53 747 72 90/91 NA 91/92 NA (-) provisional • 85 Table 5.4.1 North Minch (Functional Unit 11) : landings (in tonnes), by gear, 1982-91 , all UK Year Nephrops Trawl Other Trawl Creel Total 1982 2 323 105 371 2 799 83 2 784 95 317 3 196 84 3 449 161 534 4 144 85 3 236 117 708 4 061 86 2 642 202 538 3 382 1987 3 458 144 482 4 084 88 3 449 149 437 4 035 89 2 603 112 490 3 205 90 1 941 133 469 2 543 91 (lIf) 2 221 125 438 2 784 (lIf)provisional Table 5.4.2 North Minch (Functional Unit 11) : landings (in tonnes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and Multi-rig trawls combined (see Table 6.4 ) Year Landings Effort LPUE 1982 2 323 82.5 28.2 83 2 784 64.5 43.2 84 3 449 79.3 43.5 85 3 236 96.8 33.4 86 2 642 93.0 28.4 1987 3 458 121.2 28.5 88 3 449 115.0 30.0 89 2 603 87.9 29.6 90 1 941 79.8 24.3 91 (llf ) 2 221 93.1 23.9 (llf ) provisional Table 5.4.3 North Minch (Functional Unit 11) : mean sizes • (CL in mm) of male and female Nephrops in Scottish landings, 1982-91 Year Males Females 1982 35.0 30.6 83 32.6 29.2 84 32.6 29.1 85 33.8 29.2 86 32.5 32.5 1987 32.8 31. 4 88 32.6 31. 4 89 30.1 30.1 90 33.3 31. 7 91 34.7 31.8 86 Table 5.4.4 LCA. North Minch (Functional Unit 11): Males Cohort Analysis Output. Reference period 1980-1991 LABEL • nrrrn COHOllT ANALYSIS l INFINITY - 66.0000 K - .1630 COHOllT ANALYSIS BY POPE'S APPROXlMATlON SIZE HH REMOVAlS H OT fOT HO. ATTAINING AVE. NO. IN SEA B10HASS kg 17.0 1559.6 .3000 .2557 .0084 .0329 .3329 193633.4 47456.5 154519.2 19.0 1288.4 .3000 .2668 .0076 .0284 .3284 177836.4 45424.5 208080.4 21.0 2029.0 .3000 .2789 .0131 .0469 .3469 162920.2 43311.3 270181.0 23.0 3535.8 .3000 .2922 .0253 .0866 .3666 147897.0 40863.7 337929.3 25.0 6336.6 .3000 .3068 .0515 .1680 .4680 132100.4 3m4.8 404660.1 27.0 10082.0 .3000 .3230 .0970 .3005 .6005 114432.5 33595.3 457798.3 29.0 11775.9 .3000 .3409 .1410 .4135 .7135 94260.1 28525.3 486078.7 31.0 11944.0 .3000 .3610 .1871 .5182 .8182 73907.4 23100.4 485187.6 33.0 9913.9 .3000 .3836 .2118 .5523 .8523 55007.3 17997.0 460040.2 35.0 7765.0 .3000 .4091 .2n4 .5704 .8704 39668.6 13655.0 420065.8 37.0 5653.3 .3000 .4384 .2450 .5589 .8589 27783.7 10149.8 372015.6 39.0 3910.7 .3000 .4722 .2487 .5267 .8267 19066.2 7453.2 322569. I 41.0 2750.2 .3000 .5115 .2615 .5112 .8112 12904.8 5403.0 273884.8 43.0 1795.0 .3000 .5581 .2601 .4660 .7660 8521.8 3870. I 228091. I 45.0 1154. I .3000 .6140 .2584 .4208 .7208 5557.2 2757.2 187674.6 47.0 734.7 .3000 .6824 .2587 .3792 .6792 3569.8 1949.4 152311.3 49.0 451.9 .3000 .7679 .2559 .3332 .6332 2245.8 1365.7 121789.6 51.0 250.9 .3000 .8779 .2323 .2646 .5646 1381.0 956.0 96808.2 53.0 102.2 .3000 1.0249 .1527 .1490 .4490 841.3 691.0 79079.0 55.0 66.6 .3000 1.2311 .1636 .1329 .4329 531.0 506.7 65239.8 57.0 38.5 .3000 1.5418 .1694 .1099 .4099 311.6 356.2 51374.3 59.0 28.3 .3000 2.0642 .2648 .1283 .4283 165.6 227.0 36544.4 61.0 22.8 .3000 .1500 .4500 68.4 227.0 40640.6 TOTAL BIOHASS !NClUDES lENGTHS ABOVE +GP 368049.9 Table 5.4.5 LCA. North Minch (Functional Unit 11): Females Cohort Analysis Output. Reference period 1980-1991 LABEL. I"II\f COHOllT ANALYSIS lOliER CURVE UNF- 66.0000 K- .1630 UPPER CURVE UNF- 58.0000 K- .0600 TRANSITION lENGTH- 25.0000 COHOllT AHALYSIS BY POPE'S APPROXIHATlCN SIZE HH REHOVALS H OT fOT NO. ATTAINING AVE. NO. IN SEA BIOHASS kg 17.0 482.6 .3000 .2557 .0016 .0064 .3064 308733.4 75919.1 285364.7 • 372964.5 19.0 1270.I .3000 .2668 .0046 .0174 .3174 285474.9 73023.7 21.0 2074.9 .3000 .2789 .0083 .0297 .3297 262297.4 69894.6 471085.8 23.0 3511.6 .3000 .2922 .0155 .0529 .3529 239253.4 66425.5 576707.8 25.0 6055.0 .2000 .3068 .0294 .0957 .2957 215812.6 63299.3 693710. I 27.0 9105.9 .2000 1.1115 .0530 .0477 .2477 197095.9 191506.1 2603868.0 29.0 9755.0 .2000 1.1910 .0763 .0640 .2640 149661.0 152939. I 2541838.0 31.0 8239.0 .2000 1.2827 .0896 .0699 .2699 109280.3 118485.0 2376053.0 33.0 6359.3 .2000 1.3897 .0993 .0715 .2715 m05.9 89492.7 2140907.0 35.0 3697.0 .2000 1.5162 .0846 .0558 .2558 53012.8 66623.7 1882243.0 37.0 2119.3 .2000 1.6681 .0722 .0433 .2433 35969.0 49317.7 1630719.0 39.0 1186.2 .2000 1.8538 .0614 .0331 .2331 23972.0 36082.0 1385133.0 41.0 601.5 .2000 2.0861 .0488 .0234 .2234 15560.4 25946.4 1147992.0 43.0 303.I .2000 2.3850 .0402 .0169 .2169 9764.2 18182.3 921090. I 45.0 159.7 .2000 2.7842 .0369 .0133 .2133 5821.3 12222.2 704663. I 47.0 74.5 .2000 3.3445 .0329 .0098 .2098 3214.8 7726.1 504173.9 49.0 35.4 .2000 4.1886 .0343 .0082 .2082 1593.5 4453.8 327298.5 51.0 15.9 .2000 5.6079 .0427 .0076 .2076 666.2 2207.3 181817.9 53.0 27.I .2000 .0300 .2300 208.0 2207.3 202923.6 TOTAL BIOHASS INClUOES lEHGTHS ABOVE +GP 1132576.0 87 Table 5.4.6 VPA. North Minch (Functional Unit 11): Males Catch (OOO's) at 'nominal age'. 1980 - 1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 1446. 1760. 2011. 7467. 16249. 11962. 10862. 5529. 8586. 17285. 2554. 1693. 2 17435. 20155. 16833. 34605. 42214. 29394. 33302. 43953. 29046. 28437. 14756. 17426. 3 22739. 25287. 18268. 24674. 42258. 31830. 32507. 43210. 37450. 18555. 18411- 28345. 4 9005. 10343. 11822. 11306. 19135. 19469. 15581. 18447. 19231. 8530. 10437. 15744. 5 3650. 4571. 6027. 5075. 7914. 10127. 5818. 7203. 8658. 4090. 3719. 6806. 6 1745. 2475. 3168. 2798. 3635. 4314. 2155. 3291. 3319. 1740. 1395. 3116. 7 787. 1358. 1424. 1703. 1496. 1883. 947. 1232. 1245. 742. 568. 1286. 8 355. 706. 822. 951- 567. 768. 416. 542. 624. 371. 239. 477. 9 154. 325. 265. 317. 175. 282. 105. 219. 221. 133. 116. 183. 10 75. 169. 116. 231. 84. 143. 77. 106. 111. 68. 92. 101. 11 78. 274. 227. 343. 104. 262. 132. 186. 187. 164. 180. 191. • Table 5.4.7 VPA. North Minch (Functional Unit 11): Males Mean weight (kg) at 'nominal age'. 1980 - 1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0070 .0070 .0070 .0060 .0060 .0050 .0060 .0070 .0060 .0060 .0070 .0070 2 .0150 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0130 .0140 .0150 3 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 4 .0360 .0360 .0370 .0370 .0360 .0370 .0360 .0360 .0370 .0370 .0360 5 .0510 .0520 .0520 .0520 .0510 .0510 .0510 .0520 .0510 .0510 .0510 « 6 .0670 .0670 .0670 .0670 .0670 .0660 .0670 .0660 .0660 .0660 .0660 .0670 7 .0830 .0830 .0830 .0830 .0820 .0830 .0830 .0820 .0820 .0830 .0820 .0820 8 .0960 .0970 .0980 .0970 .0960 .0960 .0960 .0960 .0970 .0970 .0970 .0970 9 .1120 .1120 .1100 .1100 .1100 .1110 .1090 .1110 .1100 •111 0 .1120 .1110 10 .1250 .1250 .1250 .1270 .1250 .1250 .1270 .1250 .1260 .1260 .1270 .1260 11 .1440 .1520 .1510 .1520 .1540 .1560 .1500 .1560 .1550 .1660 .1550 .1540 88 • Table 5.4.8 VPA. North Minch (Functional Unit 11): Males Fishing mortality (F) at 'nominal age'. 1980 - 1991 ge 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0097 .0100 .0092 .0359 .0815 .0568 .0557 .0359 .0512 .1075 .0243 .2000 2 .1685 .2016 .1380 .2389 .3246 .2315 .2468 .37H .2982 .2661 .1401 .2550 3 .4247 .4414 .3181 .3444 .5819 .4922 .4884 .6640 .7202 .3554 .3094 .4886 4 .3613 .3933 .4311 .3746 .5589 .6732 .5441 .6548 .8302 .3959 .3913 .5382 5 .3105 .3542 .4753 .3751 .5578 .7599 .4929 .5989 .8741 .4695 .3372 .5446 6 .3104 .4042 .5047 .4801 .5760 .7906 .4001 .6625 .7109 .4822 .3241 .5990 7 .2730 .4795 .4877 .6436 .5864 .7806 .4464 .4764 .6538 .3788 .3200 .6401 8 .3152 .4753 .6937 .8254 .5224 .7972 .4399 .5681 .5389 .4671 .2242 .5536 9 .2436 .6074 .3696 .7363 .3881 .6170 .2587 .4967 .5459 .2310 .2891 .3000 10 .2772 .5207 .5170 .7350 .4989 .7316 .3817 .5137 .5795 .3590 .2778 .4979 .5795 .3590 .2778 .4979 11 .2772 .5207 .5HO .7350 .4989 .7316 .3817 .5137 .Table 5.4.9 YPA. North Minch (Functional Unit 11): Males Population numbers (OOO's) at 'nominal age'. 1980 - 1991 Age 1980 ;981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 173305. 205359. 255220. 244699. 239746. 250310. 231763. 181119. 198866. 195732. 123162. 10757. 2 129621. 127143. 150618. 187341. 174881. 163702. 175191. 162393. 129439. 139971. 130219. 89052. 3 75265. 81138. 76993. 97196. 109286. 93645. 96212. 101402. 82957. 71167. 79469. 83859. 4 34064. 36461. 38658. 41496. 51026. 45243. 42406. 43732. 38670. 29907. 36950. 43205. 5 15708. 17582. 18227. 18608. 21135. 21615. 17097. 18230. 16833. 12490. 14912. 18509. 6 7509. 8530. 9140. 8394. 9473. 8963. 7490. m6. 7420. 5203. 5786. 7885. 7 3789. 4078. 4218. ' 4087. 3847. 3945. 3011. 3719. 2955. 2700. 2380. 3100. 8 1508. 2136. 1870. 1919. 1591. 1586. 1339. 1428. 1711. 1138. 1369. 1280. 9 817. 815. 984. 692. 623. 699. 529. 639. 599. 739. 529. 811. 10 356. 475. 329. 504. 246. 313. 279. 303. 288. 257. 435. 293. 11 371. 771- 642. 750. 303. 575. 477. 530. 485. 625. 855. 556 • • Table 5.4.10 VPA. North Minch (Functional Unit 11): Males Yield (tonnes),Fbar,Total stock biomass (tonnes) , 1980 - 1991 spawning stock biomass (tannes) , Ln recruitment Year, Yield, Fbar, TSB, SSB, Log R 3- 8 1980, 1581.8, .3325, 8143.0, 8143.0, 12.06 1981, 1957.6, .4246, 8776.7, 8776.7, 12.23 1982, 1927.9, .4851, 9513.2, 9513.2, 12.45 1983, 2341.0, .5072, 10268.5, 10268.5, 12.41 1984, 3261.6, .5639, 10673.3, 10673.3, 12.39 1985, 3076.9, .7156, 9844.7, 9844.7, 12.43 1986, 2473.2, .4686, 9595.8, 9595.8, 12.35 1987, 3166.6, .6041, 9641.3, 9641.3, 12.11 1988, 2959.0, .7213, 8360.9, 8360.9, 12.20 1989, 1705.9, .4248, 7341.6, 7341.6, 12.18 1990, 1446.0, .3177, 7639.9, 7639.9, 11.72 1991, 2290.2, .5607, 7042.3, 7042.3, 9.28 89 Table 5.4.11 VPA. North Minch (Functional Unit 11): Females Catch (000'5) at 'nominal age'. 1980 - 1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 1681. 804. 2481. 9306. 10100. 10410. 8262. 2941. 2460. 17805. 3570. 2167. 2 782. 417. 1246. 3635. 3544. 3151. 2412. 1425. 1140. 3657. 1596. 945. 3 983. 502. 1504. 4732. 5068. 4523. 3309. 1819. 1410. 5587. 2082. 1240. 4 2282. 1408. 3731. 8985. 6717. 6283. 5826. 3559. 3135. 5386. 3482. 2567. 5 4520. 2692. 7014. 13255. 8705. 9187. 9036. 5175. 4942. 6744. 4487. 4242. 6 7011. 3642. 9416. 15545. 9736. 10983. 10818. 6370. 6558. 9064. 5171. 5220. 7 7976. 3833. 7237. 15489. 8814. 9291. 11805. 7356. 8301- 8781. 5087. 5473. 8 5411. 3388. 7154. 7647. 6690. 5639. 10790. 6160. 8873. 8630. 5452. 4003. 9 3209. 2517. 5488. 6187. 4644. 4367. 8818. 5438. 7479. 7601. 5158. 3112. 10 1863. 1644. 4099. 4097. 3130. 3347. 7352. 4437. 6090. 6516. 4792. 2516. 11 765. 618. 2626. 1289. 1654. 2291. 5917. 3107. 4461- 5210. 4324. 1984. 12 360. 755. 1087. 747. 1076. 1611. 4193. 1971. 2933. 3399. 2362. 1387. 13 251- 695. 729. 581- 908. 1353. 3632. 1594. 2458. 2911. 1835. 1194. 14 248. 1265. 1246. 823. 4435. 2965. 10605. 2748. 5195. 7263. 3970. 3691.• Table ~.4.1Z VPA. North Minch lFunctional Unit 11): Females Mean weight (kg) at 'nominal age' .1980 - 1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0080 .0080 .0080 .0070 .0070 .0070 .0070 .0080 .0080 .0060 .0080 .0080 2 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 3 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0070 .0080 .0080 4 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .01_ 5 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .01 6 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0150 .0140 .0140 .0140 7 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 8 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 9 .0220 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 10 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 11 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 12 .0320 .0330 .0310 .0320 .0320 .0320 .0320 .0320 .0320 .0320 .0320 .0320 13 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 14 .0440 .0470 .0450 .0430 .0550 .0460 .0470 .0440 .0440 .0470 .0450 .0480 90 Tablc 5.4.13 VPA. North Minch (Functional Unit 11): Fcmalcs .. Fishing mortality (F) at 'nominal agc' .1980 - 1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0052 .0027 .0102 .0456 .0561 .0584 .0516 .0200 .0216 .2071 .0521 .2000 2 .0029 .0016 .0054 .0195 .0231 .0234 .0181 .0118 .0102 .0426 .0270 .0184 3 .0046 .0022 .0073 .0256 .0340 .0371 .0309 .0170 .0145 .0630 .0307 .0263 4 .0123 .0080 .0206 .0549 .0459 .0538 .0614 .0421 .0367 .0705 .0508 .0481 5 .0335 .0179 .0501 .0947 .0691 .0817 .1021 .0711 .0757 .1032 .On2 .0806 6 .0685 .0341 .0804 .1496 .0933 .1167 .1304 .0972 .1210 .1932 .1074 .1210 7 .0943 .0485 .0880 .1839 .1186 .1210 .ln2 .1230 .1no .2357 .1581 .1583 8 .0940 .0527 .1201 .1262 .1128 .1036 .2011 .1320 .2138 .2816 .2252 .1797 9 .0858 .05n .1131 .1447 .1052 .1000 .2333 .1476 .2343 .2865 .2711 .1937 10 .1000 .05n .1255 .1156 .1012 .1027 .2431 .1763 .2448 .3292 .2950 .2055 11 .0683 .0436 .1230 .0528 .0624 .1001 .2653 .1535 .2697 .3416 .3793 .1909 12 .0257 .0889 .1006 .0466 .0569 .0797 .2674 .1322 .2121 .3393 .2560 .2000 13 .0644 .0632 .1161 .0716 .0734 .0941 .2584 .1539 .2421 .3366 .3100 .1987 14 .0644 .0632 .1161 .0716 .0734 .0941 .2584 .1539 .2421 .3366 .3100 .1987 Table 5.4.16 South Minch (Functional Unit 12) : landings (in tonnes), by gear,1982-91, all UK Year Nephrops Trawl Other Trawl Creel Total 1982 2 690 163 421 3 274 83 2 500 296 456 3 252 84 2 952 394 593 3 939 85 2 973 366 488 3 827 86 2 600 253 464 3 317 1987 2 881 376 450 3 707 88 3 465 351 494 4 310 89 3 665 299 451 4 415 90 3 604 227 381 4 212 91 (- ) 3 466 287 454 4 207 (-)provisional Table 5.4.17 South Minch (Functional Unit 12) : landings (in tonnes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig • trawls combined (see Table 6.4) Year Landlngs Effort LPUE 1982 2 690 98.9 27.2 83 2 500 75.4 33.2 84 2 952 87.1 33.9 85 2 973 125.0 23.8 86 2 599 102.3 25.4 1987 2 880 124.2 23.2 88 3 465 118.4 29.3 89 3 665 132.2 27.7 90 3 604 148.8 24.2 91 (- ) 3 466 145.7 23.8 (-) provisional Table 5.4.18 South Minch (Functlonal Unit 12) : mean sizes • (CL in mm) of male and female Nephrops in Scottlsh landlngs, 1982-91 Year Males Females 1982 32.0 29.8 83 32.9 30.0 84 31.6 26.9 85 32.7 28.8 86 33.5 28.3 1987 32.2 29.7 88 31.4 30.0 89 32.0 30.0 90 32.4 29.9 91 32.9 28.8 92 a abl e 5.. 4 19 VPA. South Minch (Functional Unit 12) Males Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 3090. 3438. 15517. 2173. 6206. 12022. 5038. 7538. 3922. 4638. 7872. 2707. 2 19084. 19465. 38876. 30740. 47453. 33896. 20678. 44919. 42221. 29537. 44393. 27513. 3 27117. 21377. 31211. 40534. 38768. 31284. 22664. 37852. 44918. 34179. 40982. 35646. 4 12200. 18225. 13998. 21742. 17889. 20261. 15982. 17216. 17727. 18876. 17611. 21231. 5 6603. 12091. 7477. 7360. 7397. 9716. 8086. 7381. 7890. 8282. 6092. 8294. 6 2380. 5637. 3300. 2240. 2593. 4020. 2953. 3549. 2971. 3228. 2404. 3031. 7 889. 2441. 1950. 915. 994. 1426. 1148. 1724. 1232. 1162. 1045. 1210. 8 399. 988. 1148. 377. 337. 481. 377. 634. 687. 450. 327. 421. 9 180. 521. 455. 154. 142. 175. 187. 263. 413. 244. 173. 204. 10 135. 262. 195. 92. 82. 75. 115. 158. 129. 92. 54. 52. 11 101. 310. 95. 106. 64. 52. 154. 110. 114. 73. 63. 41. fable 5.4.20 VPA. South Minch (Functional Unit 12): Males Mean weight (kg) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0050 .0060 .0060 .0060 .0060 .0050 .0060 .0060 .0060 .0060 .0060 .0060 2 .0130 .0130 .0120 .0130 .0120 .0120 .0120 .0120 .0130 .0120 .0120 .0130 3 .0220 .0230 .0220 .0230 .0220 .0230 .0230 .0220 .0220 .0230 .0230 .0230 4 .0370 .0380 .0370 .0360 .0370 .0370 .0370 .0370 .0370 .0360 .0360 .0370 .0530 .0530 .0530 .0520 .0520 .0520 .0520 .0520 .0520 .0530 .0520 .0520 .0690 .0700 .0700 .0690 .0690 .0690 .0690 .0700 .0690 .0690 .0700 .0690 7 .0860 .0870 .0880 .0870 .0870 .0860 .0870 .0870 .0870 .0870 .0870 .0870 -8 .1050 .1050 .1050 .1050 .1050 .1050 .1050 .1050 .1060 .1050 .1050 .1050 9 .1230 .1210 .1210 .1220 .1220 .1210 .1220 .1220 .1200 .1210 .1200 .1200 10 .1340 .1360 .1350 .1360 .1350 .1350 .1350 .1350 .1360 .1350 .1360 .1360 11 .1750 .1690 .1680 .1710 .1620 .1600 .1720 .1600 .1660 .1720 .1690 .1580 93 Table 5.4.21 VPA. Soulh Minch (Funclional Unil 12): Males Fishing morlalily (F) al 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0156 .0146 .0690 .0101 .0335 .0609 .0214 .0342 .0172 .0212 .0510 .2000 2 .1853 .1431 .2525 .2111 .3517 .2872 .1573 .2994 .3026 .1933 .3212 .2814 3 .4138 .3659 .4019 .5137 .5063 .4685 .3564 .5394 .6298 .4852 .5047 .5252 4 .3576 .6211 .4933 .6212 .5110 .6231 .5301 .5740 .6003 .6870 .5683 .6122 5 .4023 .8405 .6473 .6004 .5052 .6676 .6269 .5717 .6515 .7282 .5650 .6644 6 .3106 .8319 .6683 .4617 .4981 .6550 .4962 .7241 .5436 .7062 .5474 .7098 7 .2789 .6926 .9278 .4426 .4337 .6492 .4438 .7010 .6902 .4809 .59n .6806 8 .2721 .6501 .9935 .5152 .3257 .4379 .3980 .5369 .7887 .6744 .2687 .5876 9 .2326 .7848 .8365 .3738 .4203 .3146 .3417 .6112 .9630 .8536 .6939 .3000 10 .2612 .7091 .9192 .4439 .3932 .46n .3945 .6164 .8140 .6697 .5199 .5227 11 .2612 .7091 .9192 .4439 .3932 .4672 .3945 .6164 .8140 .6697 .5199 .5227 Iablc 5.4.22 VPA. South Minch (Functional Unit 12) : Males Population numbers (OOO's) at 'nominal agc' . 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 230814. 274493. 268967. 250407. 217796. 235034. 275122. 259482. 265898. 255851. 183154. 17197. 2 129999. 168332. 200390. 185973. 183636. 156030. 163824. 199479. 185770. 193607. 185547. 128943. 3 91683. 80016. 108072. 115324. 111550. 95701. 86729. 103702. 109543. 101687. 118221. 99690. 4 46550. 44902. 41111. 53561. 51109. 49804. 44377. 44986. 44791. 43229. 46369. 52869. 5 22846. 24115. 17874. 18596. 21319. 22713. 19787. 19346. 18772. 18205. 16111. 19457. 6 10237. 11319. 7709. 6932. 7558. 9529. 8630. 7832. 8092. 7249. 6511. 6783. 7 4201. 5559. 3649. 2927. 3236. 3402. 3667. 3892. 2812. 3480. 2650. 2790. 8 1927. 2355. 2060. 1069. 1393. 1554. 1317. 1743. 1430. 1045. 1594. 1081. 9 999. 1087. 911. 565. 473. 745. 743. 655. 755. 482. 394. 903. 10 673. 587. 367. 292. 288. 230. 403. 391. 263. 213. 152. 146. 11 504. 693. 180. 339. 226. 159. 542. 272. 233. 169. 176. 115 • Iable 5.4.23 VPA. South Minch (Functional Unit 12): Males Yield (tonnes),Fbar,Iotal stock biomass (tonnes),1980-1991 • spawning stock biomass (tonnes), Ln recruitment Year, YieLd, Fbar, TSB, SSB, log R 3- 8 1980, 2001.8, .3392, 9365.6, 9365.6, 12.35 1981, 2960.3, .6670, 10511.7, 10511.7, 12.52 1982, 2781.1, .6887, 10131.6, 10131.6, 12.50 1983, 2833.4, .5258, 10479.6, 10479.6, 12.43 1984, 2845.6, .4633, 10046.6, 10046.6, 12.29 1985, 2931.5, .5835, 9532.3, 9532.3, 12.37 1986, 2219.5, .4752, 9573.3, 9573.3, 12.52 1987, 2973.7, .6079, 10148.6, 10148.6, 12.47 1988, 3097.9, .6507, 10173.4, 10173.4, 12.49 1989, 2712.2, .6270, 9747.1, 9747.1, 12.45 1990, 2805.4, .5085, 9503.1, 9503.1, 12.12 1991, 2807.2, .6300, 8010.8, 8010.8, 9.75 94 ------1 Iahle 5.4.24 VPA. South Minch (Functional Unit 12) : Females Catch (000' s) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 341. 2401. 4280. 425. 1065. 2178. 1085. 1583. 448. 417. 4326. 1743. 2 17844. 17403. 22775. 14474. 36736. 28550. 14990. 21733. 20681. 29337. 51241. 39726. 3 4488. 4036. 6352. 4610. 6289. 8113. 3890. 4710. 4800. 8224. 11639. 8571. 4 959. 3730. 4597. 1180. 5108. 3656. 2261. 3817. 1911. 2379. 7989. 4579. 5 3854. 4851. 6434. 2761. 11427. 6006. 3983. 6243. 5034. 5822. 15132. 11641. 6 8025. 6146. 7775. 5532. 135n. 11056. 5150. 7654. 8446. 11878. 17952. 14842. 7 8371. 5329. 7965. 8475. 11526. 13719. 6412. 7386. 8956. 15569. 18452. 15042. 8 6626. 4748. 7490. 6598. 9509. 12179. 6401. 6800. 8630. 15791. 14760. 12069. 9 4143. 3903. 4854. 5212. 6829. 8971. 6033. 5572. 6998. 12078. 11945. 8123. 10 2693. 3210. 3173. 4159. 4972. 62n. 5313. 4456. 6714. 9055. 8661. 5235. 11 1886. 2653. 2255. 3201- 3651. 4306. 4469. 3491. 6492. 6715. 5739. 3392. 2170. 12 930. 1904. 1293. 1605. 1836. 2472. 3202. 2119. 3557. 3165. 3523. 13 581. 1516. 976. 1238. 1230. 1656. 2329. 1595. 2605. 2350. 2509. 2032. • 14 818. 3202. 3144. 2363. 2459. 3105. 5618. 3442. 6658. 6732. 5580. 6551- Iahle 5.4.25 YPA. South Minch (Functional Unit 12): Females Mean weight (kg) at 'nominal age' .1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0060 .0050 .0050 .0050 .0060 .0050 .0050 .0060 .0060 .0060 .0050 .0050 2 .0120 .0110 .0110 .0120 .0110 .0110 .0110 .0110 .0110 .0120 .0110 .0110 3 .0140 .0110 .0110 .0140 .0140 .0130 .0130 .0130 .0140 .0140 .0130 .0140 4 .0070 .0070 .0070 .0070 .0070 .0070 .0070 .0070 .0070 .0070 .0070 .0070 5 .0090 .0090 .0090 .0090 .0090 .0090 .0090 .0090 .0090 .0090 .0090 .0090 6 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 7 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 • 8 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 9 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 10 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 11 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 12 .0300 .0300 .0300 .0300 .0300 .0300 .0300 .0300 .0300 .0300 .0300 .0300 13 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0340 14 .0400 .0420 .0470 .0410 .0420 .0420 .0440 .0420 .0440 .0450 .0440 .0440 95 Tablc 5.4.26 VPA. South Minch (Functional Unit 12): Fcmalcs Fishing mortality (F) at 'nominal agc'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0008 .0057 .0097 .0008 .0020 .0037 .0016 .0019 .0006 .0005 .0049 .2000 2 .0514 .0552 .0764 .0454 .1021 .0736 .0354 .0450 .0349 .0569 .0945 .0624 3 .0185 .0155 .0271 .0209 .0263 .0311 .0135 .0147 .0132 .0183 .0304 .0216 4 .0052 .0191 .0219 .0062 .0290 .0191 .0108 .0164 .0074 .0081 .0222 .0149 5 .0264 .0325 .0415 .0164 .0769 .0432 .0260 .0373 .0270 .0279 .0649 .0408 6 .0726 .0535 .0669 .0456 .1045 .0992 .0474 .0638 .0649 .0822 .1125 .0837 7 .1011 .0630 .0910 .0965 .1261 .1461 .0768 .0888 .0988 .1634 .1n1 .1299 8 .1305 .0766 .1182 .1013 .1494 .1903 .0940 .1090 .1420 .2525 .2297 .1682 9 .1275 .1057 .1046 .1128 .1447 .2051 .1357 .1106 .1563 .3012 .3081 .1908 10 .1139 .13n .1173 .1226 .1497 .1920 .1800 .1405 .1887 .3102 .3674 .2150 11 .1166 .1568 .1355 .1663 .1506 .1872 .2033 .1724 .3117 .2920 .3305 .2393 12 .0689 .1654 .1066 .1349 .1356 .1443 .2070 .1401 .2663 .2459 .2453 .2000 13 .0994 .1528 .1195 .1410 .1451 .1743 .1966 .1509 .2554 .2826 .3142 .2180 14 .0994 .1528 .1195 .1410 .1451 .1743 .1966 .1509 .2554 .2826 .3142 .2180 Tablc 5.4.27 VPA. South Minch (Functional Unit 12): Fcmalcs Population numbcrs (OOO's) at 'nominal agc' . 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 505651. 485514. 514314. 590245. 628608. 674628. n2161. 943450. 827901. 886318. 1029619. 11073. 2 411768. 374303. 357611. 3m29. 436898. 464768. 497902. 571097. 697563. 612939. 656242. 759037. 3 270120. 289764. 262388. 245432. 267135. 292241. 319872. 356013. 404464. 499049. 428956. 442320. 4 205273. 217094. 233587. 2090n. 196n1. 213021. 231926. 258368. 287217. 326804. 401145. 340668. 5 163031. 167196. 174367. 187085. 170111. 156481. 171099. 187839. 208080. 233425. 265411- 321201. 6 126345. 129991. 132499. 136938. 150674. 128965. 122695. 136480. 148141. 165807. 185844. 203646. 7 95900. 96202. 100880. 101465. 107122. 111119. 95617. 95805. 104833. 113666. 125036. 135970. 8 59631. 70967. 73955. 75410. 75429. m13. 78613. 72500. 71m. 77753. 79036. 85752. 9 38106. 42849. 53820. 53796. 55790. 53187. 52332. 58590. 53226. 50989. 49454. 51426. 10 27543. 27464~ 31562. 39687. 39345. 39523. 35470. 37408. 42946. 37272. 30890. 29755. 11 18864. 20123. 19592. 22981. 28744. 2m3. 26706. 24256. 26612. 29115. 22378. 17514. 12 15402. 13745. 14084. 14008. 15932. 20243. 18829. 17842. 16714. 15953. 17800. 13165. 13 6760. 11n1. 9538. 10365. 10022. 11389. 14346. 12534. 12698. 10485. 10214. 11404. 14 9516. 24872. 30732. 19781. 20033. 21349. 34612. 27041. 32454. 30032. 22713. 36n1.• Tablc 5.4.28 VPA. South Minch (Functional Unit 12): Fcmalcs Yicld (tonncs),Fbar,Total stock biomass(tonncs) spawning stock biomass (tonnes) , Ln recruitment 1980-1991 Year, Yield, Fbar, 1SB, SSB, Log R 3-11 1980, 920.1, .0791, 21485.3, 13510.2, 13.13 1981, 1009.2, .0734, 20727.1, 14182.2, 13.09 1982, 1211.5, .0805, 21348.9, 14843.6, 13.15 1983, 1039.7, .0765, 22567.8, 15088.6, 13.29 1984, 1667.9, .1064, 24234.0, 15656.5, 13.35 1985, 1736.8, .1237, 24175.4, 15689.8, 13.42 1986, 1312.1, .0875, 25924.9, 16587.1, 13.56 1987, 1269.0, .0837, 29029.0, 17086.3, 13.76 1988, 1678.3, .1122, 31744.5, 19103.9, 13.63 1989, 2267.5, .1618, 33761.2, 21088.0, 13.69 1990, 2674.7, .1825, 32615.9, 20249.2, 13.84 1991, 2089.9, .1227, 30246.7, 21841.9, 9.31 96 Table 5.4.29 Clyde (Functional Unit 13) : landings (in tonnes), by gear,1982-91, all UK Year Nephrops Trawl Other Trawl Creel Total 1982 2 373 171 79 2 623 83 3 889 136 53 4 078 84 3 069 163 77 3 309 85 3 921 301 64 4 286 86 4 074 189 79 4 342 1987 2 859 84 64 3 007 88 3 505 114 43 3 662 89 2 577 193 36 2 806 90 2 731 156 24 2 911 91 (-) 2 838 168 25 3 031 (-)provisional Table 5.4.30 Clyde (Functional Unit 13) : landings (in tonnes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig trawls combined (see Table 6.4 ) Year Landings Effort LPUE 1982 2 373 113.2 21. 0 83 3 889 149.9 25.9 84 3 069 140.0 21.9 85 3 921 155.7 25.2 86 4 074 168.9 24.1 1987 2 859 144.3 19.8 88 3 505 150.7 23.3 89 2 577 150.0 17.2 90 2 731 153.4 17.8 91 (-) 2 838 165.0 17.2 (-) provisional Table 5.4.31 Clyde (Functional Unit 13) : mean sizes (CL in mm) of male and female Nephrops in Scottish landings, 1982-91 Year Males Females 1982 31.2 29.8 83 31.9 30.0 84 29.2 26.9 85 30.5 28.8 86 30.6 28.3 1987 31. 3 29.7 88 33.7 30.7 89 35.4 33.1 90 33.1 31.9 91 30.4 29.2 97 ------Table 5.4.32 LCA. Firth of Clyde (Functional Unit 13) : Males Cohort Analysis Output. Reference period 1988-1991 lA.BEL z tim COHORT ANALYSIS L INFINITY • 73.0000 K • .1600 COH~T ANALYSIS 8r POPE'S APPROXIMATION SIZE MH REMOVALS M OT FOT 2 NO. ATTAINING AVE. NO. IN SEA SIOMASS k; 15.0 57.0 .3000 .2193 .0003 .0015 .3015 175300.3 3n03.3 83001.9 17.0 503.3 .3000 .2273 .0032 .0140 .3140 164082.3 35995.8 117623.1 19.0 1718.4 .3000 .2359 .0117 .0497 .3497 152780.3 34591.2 159023. I 21.0 3967.3 .3000 .2451 .0297 .1211 .4211 140684.I 32765.5 205127.6 23.0 5948. I .3000 .2551 .0499 .1957 .4957 126885.5 30409.7 252379.7 25.0 7957.3 .3000 .2660 .0770 .2893 .5893 111811.2 27527.7 296102.0 27.0 8883.1 .3000 .277S .1019 .3668 .6668 95589.4 24242.2 331529.7 29.0 10221.5 .3000 .2908 .1444 .4965 .7965 79424.8 20613.7 352523.2 31.0 11489.5 .3000 .3049 .2118 .6946 .9946 63005.2 16572.6 349328.5 33.0 8052.3 .3000 .3206 .2004 .6252 .9252 46521.4 12905.6 331077.3 35.0 6434.4 .3000 .3379 .2178 .6446 .9446 34581.4 10004.2 308860.4 37.0 4319. I .3000 .3572 .2001 .5600 .8600 25131.2 7n9.7 284328.5 39.0 3122.2 .3000 .3789 .1970 .5199 .8199 18483.3 6020.0 261473.6 41.0 2163.5 .3000 .4034 .1859 .4609 .7609 13547.6 4705.6 239389.0 43.0 1509.0 .3000 .4312 .1762 .4085 .7085 9967. I 3703.4 219049.3 45.0 1036.0 .3000 .4632 .1640 .3540 .6540 7343.2 2934.3 200447.4 47.0 835.3 .3000 .5003 .1815 .3629 .6629 5424.0 2309.4 181085.2 49.0 555.7 .3000 .5438 .1683 .3094 .6094 3893.2 1802. I 161288.6 51.0 415. I .3000 .5957 .1772 .2975 .5975 2795.0 1400.9 142365.5 53.0 270.9 .3000 .6585 .1657 .2517 .5517 1957.9 1081. I 124155.6 55.0 182.4 .3000 .7361 .1620 .2201 .5201 1361.5 832.7 107592.4 57.0 138.8 .3000 .8346 .1856 .2224 .5224 928.4 628.0 90915.4 59.0 111.7 .3000 .9634 .2420 .2512 .5512 600.4 448.8 n507.6 61.0 63.7 .3000 1.1395 .2407 .2112 .5112 353.0 304.9 54782.3 • 63.0 39. I .3000 1.3946 .2801 .2009 .5009 197.I 197.9 39404.9 65.0 26.3 .3000 1.7980 .4317 .2401 .5401 98.0 112.8 24817.2 67.0 14.9 .3000 .2000 .5000 37.I 112.8 24817.2 TOTAL 810MASS INCLUOES LENGTHS A80VE +GP 317155.8 Table 5.4.33 LCA. Firth of Clyde (Functional Unit 13) : Females Cohort Analysis Output. Reference period 1988-1991 LABEL. cl f COHORT ANALYSIS LOIIER CURVE UHF. 73.0000 K' .1600 UPPER CURVE UHF. 62.0000 K· .0600 • TRANSITION LENGTH. 27.0000 COHORT ANALYSIS SY POPE'S APPROXIMATION SllE MH REMOVALS M OT FOT NO. ATTAINING AVE. NO. IN SEA SIOMASS kll 13.0 3.8 .3000 .2119 .0000 .0000 .3000 768877.0 157842.9 288612. I 15.0 31.I .3000 .2193 .0000 .0002 .3002 721520.4 153147.4 413005.3 17.0 1082.6 .3000 .2273 .0017 .0073 .3073 675545. I 148309.9 563468.9 19.0 2563.5 .3000 .2359 .0042 .0179 .3179 629969.4 143160.8 739057.3 21.0 5385.3 .3000 .2451 .0096 .0392 .3392 584457.2 137473.3 936537.8 23.0 8438.9 .3000 .2551 .0164 .0644 .3644 537828.3 131033.9 1149887.0 25.0 9470.9 .3000 .2660 .0203 .0764 .3764 490076.3 124046.0 1374080.0 27.0 9320.4 .2000 .2778 .0219 .0786 .2786 443387.9 118536.1 1629061.0 29.0 9223.1 .2000 1.0420 .0253 .0242 .2242 410358.1 381313.5 6405630.0 31.0 7337.2 .2000 1.1115 .0256 .0230 .2230 324851.6 319808.8 6482369.0 33.0 576S.5 .2000 1.1910 .Ol60 .Ol18 .2218 253534.0 265365.5 6416599.0 35.0 3944.1 .2000 1.2827 .0233 .0182 .2182 194678.7 217815.3 6219930.0 37.0 2717.4 .2000 1.3897 .0214 .0154 .2154 147158.8 176732.0 5906663.0 39.0 1992.6 .2000 1.5162 .0215 .0142 .2142 109084.9 141225.6 5479800.0 41.0 1343.3 .2000 1.6681 .0203 .0122 .2122 78838.5 110752.9 4952989.0 43.0 931.6 .2000 1.8538 .0205 .0110 .2110 55337.6 84896.0 4347018.0 45.0 557.3 .2000 2.0861 .0185 .0089 .2089 37420.9 63277.9 3687520.0 47.0 332. I .2000 2.3850 .0176 .0074 .2074 24203.6 45539.9 3003728.0 49.0 233.8 .2000 2.7842 .0211 .0076 .2076 14760.0 31211.3 2318312.0 51.0 161.6 .2000 3.3445 .0276 .0083 .2083 8280.7 19947.7 1660807.0 53.0 99.6 .2000 4.1886 .0374 .0089 .2089 4126.3 11518.0 1070283.0 55.0 54.1 .2000 5.6079 .0567 .0101 .2101 1720.0 5666.3 585302.3 57.0 58.8 .2000 .0250 .2250 529.4 5666.3 648229.1 98 TOTAL SIOHASS INCLUDES UHGTNS ABOVE +GP 2999954.0 Table 5.4.34 VPA. Firth of Clyde (Functional Unit 13): Males Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 441. 2791- 13383. 16697. 71674. 35487. 33983. 10924. 2835. 2494. 13n9. 12624. 2 16896. 32156. 44893. 61476. 66398. 62316. 67987. 49161. 23531- 10067. 32247. 57008. 3 19759. 26356. 20370. 36603. 24015. 28951. 25565. 25732. 31546. 16524. 27001. 32201. 4 11882. 8066. 6100. 11307. 7600. 8321. 9730. 7185. 11358. 9368. 7345. 6838. 5 5343. 3315. 2198. 4281. 2768. 2951. 3476. 2092. 4952. 3700. 2511. 1467. 6 2186. 1255. 864. 1309. 990. 900. 1586. 691. 2454. 1658. 942. 401- 7 1051. 740. 529. 666. 354. 291. 789. 344. 1069. 907. 374. 119. 8 538. 364. 280. 390. 212. 168. 339. 170. 417. 514. 228. 38. 9 387. 169. 147. 216. 96. 82. 149. 89. 209. 291. 147. 11. 48. 6. 10 288. 88. 98. 109. 50. 64. 31. 145. 186. 90. 11 351. 155. 138. 182. 89. 61. 46. 80. 152. 217. 161. 12. • Table 5.4.35 VPA. Firth of Clyde (Functional Unit 13): Males Mean weight (kg) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0080 .0060 .0060 .0060 .0050 .0050 .0060 .0060 .0060 .0060 .0060 .0060 2 .0140 .0140 .0120 .0130 .0120 .0120 .0120 .0130 .0140 .0130 .0130 .0130 3 .0250 .0250 .0250 .0240 .0250 .0250 .0250 .0250 .0250 .0260 .0250 .0250 4 .0420 .0410 .0410 .0420 .0410 .0410 .0410 .0410 .0420 .0420 .0410 .0410 .0600 .0610 .0610 .0600 .0610 .0600 .0610 .0600 .0610 .0610 .0600 .0600 .56 .0830 .0830 .0830 .0820 .0820 .0820 .0820 .0820 .0820 .0830 .0820 .0820 7 .1040 .1030 .1040 .1040 .1040 .1030 .1030 .1040 .1030 .1040 .1030 .1030 8 .1220 .1240 .1230 .1240 .1240 .1240 .1240 .1220 .1220 .1230 .1240 .1210 9 .1460 .1440 .1450 .1450 .1440 .1450 .1440 .1440 .1450 .1450 .1450 .1440 10 .1630 .1640 .1640 .1630 .1630 .1630 .1630 .1650 .1630 .1630 .1630 .1640 11 .2000 .1950 .1980 .1990 .2030 .2120 .1950 .1960 .1960 .2010 .2030 .1960 99 Table 5.4.36 VPA. Firth of Clyde (Functional Unit 13): Males I Fishing mortality (F) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0033 .0162 .0750 .0845 .3455 .1780 .1960 .1163 .0301 .0169 .0654 .2000 2 .2232 .3928 .4333 .6462 .6297 .6553 .6883 .5436 .4398 .1580 .3490 .4679 3 .6331 .7338 .5277 .8922 .6517 .7236 .7173 .7047 .9656 .7336 .9369 .8132 4 .7902 .6665 .4170 .7303 .5232 .5633 .6587 .5107 .9323 1.0517 1.0353 .7610 5 .7341 .•6077 .4316 .6676 .4432 .4477 .5563 .3186 .9509 1.1219 1.1171 .6804 6 .6051 .4249 .3511 .5664 .3550 .2818 .5258 .2250 .8822 1.2472 1.2378 .5954 7 .5723 .4800 .3592 .5710 .3283 .1861 .4837 .2285 .7342 1.2075 1.3992 .5537 8 .5112 .4500 .3791 .5583 .4029 .2869 .3853 .2007 .5380 1.1881 1.5608 .5487 9 .7453 .3335 .3703 .6453 .2893 .2999 .5030 .1843 .4572 1.0880 1.9899 .3000 10 .6095 .4212 .3695 .5915 .3402 .2576 .4573 .2045 .5765 1.1612 1.6500 .4675 11 .6095 .4212 .3695 .5915 .3402 .2576 .4573 .2045 .5765 1.1612 1.6500 .4675 Table 5.4.37 VPA. Firth of Clyde (Functional Unit 13): Males Population numbers (000'5) at 'nominal age'. 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 153692. 200614. 214087. 237896. 281544. 250799. 219884. 114824. 110466. 172466. 251540. 80211. 2 97238. 113478. 146216. 147145. 161950. 147633. 155500. 133895. 75724. 79406. 125619. 174549. 3 48000. 57628. 56758. 70230. 57126. 63918. 56791. 57880. 57591. 36136. 50227. 65645. 4 24694. 18879. 20496. 24804. 21320. 22056. 22965. 20534. 21194. 16244. 12855. 14580. 5 11679. 8301. 7182. 10007. 8852. 9359. 9301. 8804. 9128. 6181. 4204. 3382. 6 5492. 4153. 3349. 3455. 3802. 4210. 4431. 3950. 4743. 2613. 1491. 1019. 7 2752. 2222. 2011. 1746. 1453. 1975. 2353. 1940. 2337. 1454. 556. 320. 8 1535. 1150. 1018. 1040. 731. 775. 1215. 1074. 1144. 831. 322. 102. 9 836. 682. 543. 516. 441. 362. 431. 612. 651. 495. 188. 50. 10 718. 294. 362. 278. 201. 245. 199. 193. 377. 305. 123. 19. 11 876. 518. 510. 464. 355. 306. 144. 495. 396. 355. 221. 36 • • Table 5.4.38 VPA. Firth of Clyde (Functional Unit 13): Males Yleld (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recrultment.1980-1991 Year, Yield, Fbar, 1SB, SSB, log R 3- 8 1980, 2083.3, .6410, 6872.3, 6872.3, 11.94 1981, 1953.4, .5605, 6477.0, 6477.0, 12.21 1982, 1738.2, .4110, 6588.2, 6588.2, 12.27 1983, 2819.6, .6643, 7474.5, 7474.5, 12.38 1984, 2420.5, .4507, 6915.2, 6915.2, 12.55 1985, 2324.3, .4149, 6891.4, 6891.4, 12.43 1986, 2564.0, .5545, 6992.8, 6992.8, 12.30 1987, 1914.8, .3647, 6120.5, 6120.5, 11.65 . 1988, 2360.1, .8339, 5612.2, 5612.2, 11.61 1989, 1605.8, 1.0917, 4729.1, 4729.1, 12.06 1990, 1841.2, 1.2145, 5489.0, 5489.0, 12.44 1991, 2044.9, .6587, 5338.5, 5338.5, 11.29 100 • Table 5.4.39 VPA. Firth of Clyde (Functional Unit 13) : Females Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 327. 2238. 12725. 15179. 63158. 20558. 40584. 4973. 2138. 2824. 10278. 8765. 2 14335. 31571. 40626. 62445. 87328. 96320. 100082. 48734. 31357. 13579. 34021. 50031. 3 3908. 8144. 6974. 13809. 8160. 13547. 9966. 8018. 10284. 4710. 9905. 8863. 4 4030. 6945. 5025. 8569. 4859. 8518. 7824. 4793. 7793. 4956. 6841. 6352. 5 3600. 5111. 3522. 4958. 2454. 5334. 5766. 2729. 5001. 5462. 4913. 3988. 6 2888. 2974. 1853. 3803. 1023. 3202. 3684. 1542. 2618. 4362. 3791. 2413. 2482. 1105. 7 2614. 2093. 1522. 2664. 677. 2179. 1776. 3495. 2755. 1623. 8 2326. 1604. 1345. 1853. 521. 1551. 1685. 863. 1405. 2746. 1999. 1153. 9 1655. 1239. 897. 1301. 287. 1022. 995. 634. 1299. 1726. 1401. 831. 10 1190. 921- 695. 811. 213. 675. 724. 494. 1068. 1174. 1073. 545. 11 976. 770. 598. 585. 178. 511. 594. 427. 957. 916. 915. 411- 12 876. 539. 391- 496. 105. 279. 264. 311. 664. 578. 542. 226. 13 810. 512. 363. 458. 97. 256. 241- 296. 607. 539. 503. 208. 14 2537. 1579. 772. 1130. 348. 736. 598. 1437. 1986. 2096. 1222. 510. e Table 5.4.40 VPA. Firth of Clyde (Functional Unit 13): Females· Mean weight (kg) at 'nominal age' .1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0070 .0060 .0060 .0050 .0050 .0050 .0050 .0060 .0070 .0050 .0050 .0050 2 .0120 .0120 .0100 .0110 .0100 .0110 .0100 .0110 .0120 .0110 .0110 .0110 3 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 4 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0200 .0210 .0200 .0200 5 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0280 .0280 .0280 .0280 .0270 .0280 .0280 .0280 .0280 .0280 .0280 .0280 ~ .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 8 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 9 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 10 .0420 .0420 .0420 .0420 .0420 .0420 .0420 .0420 .0420 .0420 .0420 .0420 11 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 12 .0510 .0510 .0510 .0510 .0510 .0510 .0510 .0510 .0510 .0510 .0510 .0510 13 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 14 .0680 .0660 .0650 .0680 .0740 .0710 .0680 .0750 .0740 .0740 .0670 .0680 101 ,------ Tablc 5.4.41 VPA. Firth of Clydc (Functional Unit 13) : Fcmalcs Fishing mortality (F) at 'nominal agc'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0023 .0134 .0646 .0644 .2429 .0849 .2286 .0388 .0187 .0202 .0589 .2000 2 .1785 .3619 .3983 .5738 .7100 .8166 .8476 .5330 .4059 .1754 .3991 .5015 3 .0718 .1544 .1333 .2424 .1414 .2348 .1875 .1509 .2145 .1027 .1986 .1810 4 .1007 .1760 .1345 .2403 .1257 .2150 .2067 .1293 .2146 .1519 .2125 .1888 5 .1159 .1790 .1270 .1904 .1001 .1976 .2209 .1031 .1933 .2293 .2212 .1847 6 .1171 .1323 .0909 .1965 .0544 .1834 .2037 .0844 .1361 .2573 .2464 .1610 7 .1696 .1165 .0927 .1826 .0485 .1570 .2112 .0866 .1322 .2706 .2566 .1582 8 .1814 .1491 .1020 .1557 .0491 .1494 .1749 .1054 .1511 .3094 .2450 .1622 9 .1628 .1387 .1165 .1356 .0325 .1285 .1349 .0921 .2282 .2802 .2563 .1521 10 .1358 .1281 .1075 .1466 .0295 .0994 .1261 .0917 .2207 .3320 .2816 .1498 11 .1449 .1221 .1148 .1242 .0433 .0919 .1191 .1020 .2572 .2989 .4686 .1656 12 .1470 .1113 .0839 .1314 .0294 •0884 .0627 .0844 . .2275 .2438 .2902 .2000 13 .1420 .1201 .1018 .1338 .0340 .0932 .1026 .0926 .2350 .2915 .3466 .1717 14 .1420 .1201 .1018 .1338 .0340 .0932 .1026 .0926 .2350 .2915 .3466 .1717 Table 5.4.42 VPA. Firth of Clyde (Functional Unit 13): Fcmalcs Population numbers (OOO's) at 'nominal age'. 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 161377. 193932. 235013. 281282. 336980. 291707. 228604. 151138. 133809. 163218. 207635. 55689. 2 101072. 119270. 141743. 163208. 195384. 195807. 198511. 134750. 107706. 97288. 118484. 145019. 3 62141. 62638. 61525. 70508. 68116. 71160. 64103. 63006. 58575. 53168. 60479. 58887. 4 46349. 47351. 43946. 44087. 45303. 48415. 46070. 43508. 44360. 38700. 39283. 40598. 5 36228. 34313. 32513. 31451. 28385. 32710. 31972. 30675. 31301. 29304. 27219. 26004. 6 28781. 26415. 23490. 23444. 21286. 21026. 21978. 20987. 22654. 21124. 19077. 17863. 7 18437. 20960. 18947. 17560. 15770. 16504. 14331. 14678. 15792. 16188. 13371. 12208. 8 15423. 12740. 15274. 14139. 11978. 12300. 11549. 9499. 11020. 11328. 10111. 8469. 9 12118. 10532. 8985. 11293. 9907. 9337. 8673. 7938. 6999. 7757. 6807. 6479. 10 10321. 8431. 7506. 6548. 8073. 7852. 6723. 6205. 5928. 4561. 4799. 4313. 11 7961. 7377. 6073. 5519. 4630. 6417. 5820. 4852. 4635. 3892. 2679. 2965. 12 7047. 5638. 5346. 4433. 3991. 3630. 4793. 4230. 3587. 2934. 2363. 1373. 13 6732. 4981. 4130. 4024. 3182. 3173. 2721. 3685. 3183. 2339. 1882. 1447. 9932. 11473. 9114. 14 21101. 15364. 8780. 6759. 17888. 10423. 9103. 4576. 355. Table 5.4.43 VPA. Firth of Clydc (Functional Unit 13): Females Yield (tonnes),Fbar,Total stock biomass (tonnes) , spawning stock biomass (tonnes) , Ln rccruitment.1980-1991 Year, Yield, Fbar, TSB, SSB, Log R 3-11 1980, 1066.4, .1333, 10505.8, 8163.3, 11.99 1981, 1274.9, .1440, 9910.2, 7315.3, 12.18 1982, 1111.0, .1132, 9294.1, 6466.5, 12.37 1983, 1777.0, .1793, 9793.0, 6591.3, 12.55 1984, 1614.4, .0694, 10006.7, 6368.0, 12.73 1985, 2072.0, .1619, 10074.0, 6461.6, 12.58 1986, 2068.0, .1761, 9086.9, 5958.8, 12.34 1987, 1174.0, .1050, 8969.7, 6580.6, 11.93 1988, 1369.1, .1942, 8212.2, 5983.0, 11.80 1989, 1173.0, .2480, 7398.7, 5512.5, 12.00 1990, 1384.8, .2652, 7213.6, 4872.1, 12.24 1991, 1255.4, .1670, 6431.5, 4557.8, 10.93 102 Table 5.4.44 Nephrops landings (tonnes by Functional Unit plus other rectangles in Management Area (VIa) - (Area C) Year FU11 FU12 FU13 Other rectangles Total 1982 2799 3274 2623 + 8696 1983 3196 3252 4078 194 10720 1984 4144 3939 3309 4 11396 1985 4061 3827 4286 286 12460 1986 3382 3317 4342 259 11300 1987 4084 3707 3007 452 11250 1988 4035 4310 3662 697 12704 1989 3205 4415 2806 556 10982 1990 2543 4212 2911 406 10072 • 1991 2784 4207 3031 470 10492 Table 5.4.45 Total Nephrops landings (t) by country in Management Area (VIa) - (Area C) Year UK Spain TOTAL 1982 8696 0 8696 1983 10720 0 10720 1984 11396 0 11396 1985 12460 0 12460 1986 11296 4 11300 1987 11250 ? 11250 1988 12704 ? 12704 1989 10975 7 10982 • 1990 10071 1 10072 1991 10473 19 10492 103 Table 5.6.1 Skagerrak (Functional Unit 3) landings (in tonnes), by country, 1982-91 Year Derunark Norway Sweden Total Trawl Creel 1982 1 090 8 372 1 470 83 1 589 51 560 2 200 84 1 749 97 830(") 2 676 85 1 334 72 785(") 2 191 86 1 054 64 800 100 2 018 1987 1 385 80 865 110 2 440 88 1 260 89 886 114 2 349 89 1 795 70 643 65 2 603 90 1 749 146 860 110 2 865 91 (. ) 1 639 194 949 151 2 933 (.) provisional ( .. ) may include catches by creels Table 5.6.2 Skagerrak (Functional Unit 3) : catches and • landings (in tonnes), effort (in '000 hours trawling), CPUE and LPUE (in kg/hour trawling) of Swedish Nephrops trawlers 1982-91 Single Trawl. Twin Trawl (1990 - 91) in parenthesis. Year Catches Landings Effort CPUE LPUE 1982 ? 300 40.0 ? 7.5 83 ? 497 51.6 ? 9.6 84 ? 745 69.3 ? 10.8 85 ? 642 66.0 ? 9.7 86 ? 715 74.0 ? 9.7 1987 ? 775 91.3 ? 8.5 88 ? 700 108.8 ? 6.4 89 ? 555 97.1 ? 5.7 90 729(302) 490(203) 73.5(17.1) 9.9(17.7) 6.7(11.9) 91 676(740) 401(439) 71. 4(39. 5) 9.5(18.7) 5.6(11.1) • Table 5.6.3 Skagerrak (Functional Unit 3) : effort (in days trawling), LPUE (in kg/day trawling) of Danish Nephrops trawlers 1987-91 Year Effort LPUE 1987 16591 84.1 1988 15094 84.3 1989 19800 86.3 1990 21830 80.3 1991 17368 74.6 104 Table 5.6.4 Kattegat (Functional Unit 4) landings (in tannes) , by country, 1982-91 Year Denmark Sweden Total 1982 1 611 217 1 828 83 1 330 142 1 472 84 1 842 194 2 036 85 1 609 189 1 798 86 1 593 214 1 807 1987 1 454 151 1 605 88 1 204 160 1 364 89 1 222 91 1 313 90 1 349 127 1 476 91 (-) 1 185 130 1 315 (-) provisional Table 5.6.5 Kattegat (Functional Unit 3) : effort (in days • LPUE (in kg/day trawling) trawling) , of Danish Nephrops trawlers 1987-91 Year Effort LPUE 1987 17520 84.2 1988 14622 83.4 1989 19149 63.8 1990 18306 74.0 1991 18327 74.9 Table 5.6.6- Kattegat (Functional Unit 4) : catches and landings (in tonnes), effort (in '000 hours trawling), CPUE and LPUE (in kg/hour trawling) of Swedish Nephrops trawlers,Single 1982-91 • Twin Trawl (1990-1991) in parenthesis. Year Catches Landings Effort CPUE LPUE 1982 ? 177 14.3 ? 12.4 83 ? 87 11. 7 ? 7.4 84 ? 127 13.7 ? 9.3 85 ? 99 11. 6 ? 8.5 86 ? 137 16.2 ? 8.5 1987 ? 109 19.4 ? 5.6 88 ? 100 16.8 ? 6.0 89 ? 67 19.6 ? 3.4 90 114(25) 77(17) 14.2(1.9) 8.0(13.2) 5.4(9.1) 91 (-) 66(93) 39(55) 10.3(8.8) 6.4(10.6) 3.7(6.2) • Provislonal 105 Table 5.6.7 LCA. Skagerrak/Kattegat (Functional Unit 3&4) : Males Cohort Analysis Output. Reference ,period 1990-1991 LABEL • ~s~ COHORT ANALYSIS l INFINITY • 75.0000 K • .1600 COHOilT ANALYSIS BY POPE'S APPROXIMATION SIZE .... REHOVALS H OT FOT NO. AHAINING AVE. NO. IN SEA BIOMASS kg 16.0 15.8 .3000 .2155 .0001 .0003 .3003 293661.7 61290.7 193396.0 18.0 52.5 .3000 .2232 .0002 .0009 .3009 275258.7 59429.9 264\40.9 20.0 710.3 .3000 .2315 .0029 .0124 .3124 257377.2 57481.4 347722.5 22.0 1893.8 .3000 .2404 .0082 .0342 .3342 239422.4 55308.6 442775.8 24.0 3031.5 .3000 .2500 .0143 .0574 .3574 220935.5 52845.0 546926.8 26.0 5632.5 .3000 .2605 .0294 .1129 .4129 202049.6 49893.5 654507.1 28.0 6681.0 .3000 .2718 .0391 .1439 .4439 181446.5 46455.3 759435.6 30.0 8422.5 .3000 .284\ .0562 .1978 .4978 160825.3 42612.3 855457.7 32.0 10783.0 .3000 .2977 .0842 .2829 .5829 139613.2 38153.6 928600.3 34.0 11176.5 .3000 .3126 .1051 .3363 .6363 117373.8 33268.8 970591.2 36.0 11946.8 .3000 .3290 .1398 .4249 .7249 96203.4 28161.5 974958.9 38.0 11114.8 .3000 .3473 .1678 .4832 .7832 75789.6 23046.2 938314.7 40.0 9875.0 .3000 .3678 .1993 .5420 .8420 5nl9.8 18260.9 867294.8 42.0 7971.3 .3000 .3908 .2225 .5695 .8695 42363.4 14034.6 771883.3 44.0 5221.0 .3000 .4168 .2037 .4887 .7887 30159.9 10714.0 677820.3 46.0 4203.8 .3000 .4466 .2320 .5194 .8194 21710.2 8119.9 587329.3 48.0 3338.8 .3000 .4810 .2723 .5660 .8660 15056.4 5923.2 487111.5 50.0 1824.0 .3000 .5211 .2215 .4250 .7250 9926.9 4308.2 400759.3 52.0 975.0 .3000 .5686 •1697 .2984 .5984 6803.3 3278.8 343363.0 54.0 904.0 .3000 .6255 .2295 .3670 .6670 4841.1 2475.9 290622.2 56.0 466.0 .3000 .6952 .1769 .2545 .5545 3189.8 1840.0 241098.2 58.0 296.0 .3000 .7823 .1666 .2129 .5129 2169.5 1398.0 203699.5 60.0 288.0 .3000 .8944 .2572 .2875 .5875 1452.5 1010.4 163151.5 • 62.0 198.0 .3000 1.044\ .3142 .3010 .60\0 858.8 666.0 118774.\ 64.0 168.0 .3000 1.2542 .5837 .4654 .7654 458.6 369.7 72592.5 66.0 40.0 .3000 1.5707 .3402 .2166 .5166 175.6 188.9 40720.1 68.0 39.0 .3000 .3000 .6000 78.0 188.9 44581.4 TOTAL BIOMASS INCLUOES LENGTHS ABOVE Table 5.6.8 LCA. Skagerrak/Kattegat (Functional Unit 3&4): Females Cohort Analysis Output. Reference period 1990-1991 LABEL' FSK COHORT ANALYSIS l INfUUTY • 65.0000 K • .1000 CONORT ANALYSIS BY POPE'S APPROXIMATION SI2E .... REMOVALS M OT FOT Z NO. AHAINING AVE. NO. IN SEA BIOMASS kg 16.0 8.3 .2000 .4167 .0000 .0000 .2000 415999.4 166328.7 646779.4 18.0 88.5 .2000 .4349 .0002 .0006 .2006 382725.4 159377.8 837765.7 20.0 514.5 .2000 .4546 .0015 .0034 .2034 350761.3 152314.5 1050094.0 • 22.0 2409.0 .2000 .4763 .0079 .0167 .2167 319783.8 144712.0 1276614.0 24.0 3526.5 .2000 .5001 .0129 .0259 .2259 288431.3 136397.1 1508326.0 26.0 4459.5 .2000 .5264 .0184 .0350 .2350 257623.5 127569.6 1737863.0 28.0 6543.8 .2000 .5557 .0309 .0555 .2555 227647.3 117932.1 1949858.0 30.0 8280.0 .2000 .5884 .0455 .Onl .2nl 19751\.9 107231.1 2124142.0 32.0 12999.0 .2000 .6252 .0861 .1377 .3377 167777.2 94562.1 2219027.0 34.0 11780.0 .2000 .6669 .0973 .1459 .3459 135845.6 80907.8 2226832.0 36.0 10362.5 .2000 .7146 .1089 .1524 .3524 107862.6 68138.2 2180169.0 38.0 9722.5 .2000 .7696 .1338 .\738 .3738 83850.2 56078.5 2069444.0 40.0 10\19.5 .2000 .8338 .1923 .2306 .4306 62885.7 44054.5 1861688.0 42.0 7370.3 .2000 .9097 .2031 .2233 .4233 43916.5 33159.0 1594315.0 44.0 6312.5 .2000 1.0008 .2659 .2657 .4657 29881.6 23904.7 1300055.0 46.0 3695.8 .2000 1.1123 .2488 .2237 .4237 18749.6 16629.0 1017478.0 48.0 2981.3 .2000 1.2516 .3407 .2722 .4722 11703.3 11060.0 757635.3 50.0 \792.5 .2000 1.4310 .3844 .2686 .4686 6481. I 6757.4 515904.5 52.0 1012.0 .2000 1.6705 .4476 .2679 .4679 33\4.5 3841.8 325530.8 54.0 226.0 .2000 2.0067 .2010 .1002 .3002 1516.8 2286.4 214195.8 56.0 260.0 .2000 2.5131 .5150 .2049 .4049 830.5 1309.6 135154.5 58.0 150.0 .2000 3.3647 1.2027 .3575 .5575 300.2 455.9 51663. I 60.0 23.0 .2000 .2000 .4000 46.0 455.9 56547.8 TOTAL BIOHAS$ INClUDES LENGTHS ABOVE 106 Table 5.6.9 Nephrops landings (tonnes by Functional Unit plus other rectangles in Management Area (E) - (lIla) Year FU3 FU4 Other rectangles Total 1982 1470 1828 3298 1983 2200 1472 3672 1984 2676 2036 4712 1985 2191 1798 3989 1986 2018 1807 3825 1987 2440 1605 4045 1988 2349 1364 3713 1989 2603 1313 3916 1990 2865 1476 4341 1991 2933 1315 4248 • Table 5.6.10 Total Nephrops landings (t) by country in Management Area (E) - (lIla) Year Denmark Norway Sweden TOTAL 1982 2701 8 589 3298 1983 2919 51 702 3672 1984 3591 97 1024 4712 1985 2943 72 974 3989 1986 2647 64 1114 3825 1987 2839 80 1126 4045 1988 2464 89 1160 3713 1989 3017 70 829 3916 1990 3098 146 1097 4378 • 1991 2824 194 1230 4248 107 Table 5.7.1 Moray Firth (Functional Unit 9) : landings (ln tannes), by gear,1982-91, all UK Year Nephrops Trawl Other Trawl Total 1982 1 034 86 1 120 83 850 90 940 84 960 209 1 170 85 1 908 173 2 081 86 1 933 210 2 143 1987 1 723 268 1 991 88 1 638 321 1 959 89 2 102 474 2 576 90 1 700 338 2 038 91 1 284 233 1 517 (-)provisional Table 5.7.2 Moray Firth (Functional Unit 9) : landings (in tannes), effort (in '000 hours trawling) and LPUE (ln kg/hour trawllng) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig trawls comblned (see Table 6.4 ) • Year Landings Effort LPUE 1982 1 034 28.2 36.7 83 850 21.4 39.7 84 960 23.2 41.4 85 1 908 49.2 38.8 86 1 933 51.6 37.5 1987 1 723 70.6 24.4 88 1 638 60.9 26.9 89 2 102 69.6 30.2 90 1 700 58.4 29.1 91 1 284 47.1 27.3 (-) provisional Table 5.7.3 Moray Firth (Functional Unit 9) : mean sizes (CL in mm) of male and female Nephrops in • Scottish landings, 1982-91 Year Males Females 1982 34.4 30.3 83 33.8 31.3 84 32.3 31.0 85 31.0 29.8 86 30.9 28.9 1987 30.9 29.6 88 31.2 30.8 89 30.2 29.2 90 32.4 32.0 91 32.0 29.7 108 Iable 5.7.4 VPA. Moray Firth (Functional Unit 9): Males Catch (OOO's) at 'nominal age' . 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 12. 18. 65. 176. 438. 704. 334. 1119. 567. 384. 184. 112. 2 927. 963. 3837. 4843. 13185. 38129. 25200. 36348. 21482. 17974. 8078. 7959. 3 8983. 8578. 5656. 8064. 15912. 31287. 28655. 32129. 19697. 41000. 20747. 21540. 4 11665. 9518. 5710. 6939. 11482. 16407. 14446. 15436. 12520. 21882. 18931. 15474. 5 5536. 7045. 3443. 3348. 5168. 7993. 5189. 6734. 6066. 9228. 8411. 5966. 6 1263. 4155. 1964. 1697. 2352. 2874. 2124. 2430. 2n9. . 3449. 2357. 1542. 7 154. 1755. 822. 695. n2. 787. 796. 853. 960. 989. 541- 362. 8 14. 697. 379. 372. 293. 312. 265. 488. 518. 325. 201- 105. 9 O. 393. 345. 704. 238. 189. 95. 345. 628. 532. 149. 49 • • Iable 5.7.5 VPA. Moray Firth (Functional Unit 9): Males Mean weight (kg) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0020 .0020 .0030 .0030 .0030 .0030 .0030 .0030 .0030 .0030 .0020 .002 2 .0090 .0100 .0070 .0070 .0070 .0070 .0080 .0070 .0070 .0080 .0080 .00l 3 .0160 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0150 .01L • 4 .0240 .0250 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .0240 .02L 5 .0350 .0360 .0360 .0350 .0350 .0350 .0350 .0350 .0360 .0350 .0350 .03~ 6 .0470 .0480 .0480 .0480 .0480 .0480 .0480 .0480 .0480 .0480 .0470 .04i 7 .0610 .0620 .0620 .0620 .0620 .0620 .0620 .0620 .0620 .0610 .0620 .06, 8 .0690 .0740 .0730 .0740 .0730 .0730 .0720 .0740 .0750 .0740 .0730 .07, 9 .0000 .0840 .0860 .0870 .0850 .0850 .0840 .0850 .0860 .0840 .0850 .08~ 109 Table 5.7.6 VPA. Moray Firth (Functional Unit 9) : Males Fishing mortality (F) at 'nominal age' . 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0002 .0002 .0006 .0012 .0024 .0042 .0019 .0060 .0039 .0030 .0025 .2000 2 .0204 .0185 .0557 .0601 .1248 .3347 .2276 .3235 .1693 .1832 .0887 .1571 3 .2750 .2962 .1598 .1768 .3190 .5470 .5134 .5731 .32n .6347 .3738 .4025 4 .52n .5962 .3699 .3364 .4607 .7295 .6037 .6656 .5235 .8534 .7992 .6046 5 .4697 .8267 .5090 .4366 .5114 .7885 .6157 .7337 .6957 1.1230 1.1837 .7368 6 .2793 .9184 .6648 .5811 .7248 .6910 .5670 .7676 .9178 1.4210 1.2488 .8334 7 .0932 .9034 .5207 .6015 .6598 .6570 .4690 .5345 .9496 1.2604 1.1093 .7360 8 .2807 .8828 .5648 .5397 .6320 .7122 .5505 .6786 .8544 1.2682 1.1806 .7688 9 .2807 .8828 .5648 .5397 .6320 .7122 .5505 .6786 .8544 1.2682 1.1806 .7688 Table 5.7.7 VPA. Moray Firth (Functional Unit 9): Males Population numbers (OOO's) at 'nominal age' . 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 81987. 110494. 129527. 175265. 208226. 193121. 204217. 215884. 167628. 148784. 85406. 708. 2 52971. 60727. 81840. 95900. 129688. 153880. 142462. 151001. 158967. 123694. 109892. 63112. 3 42958. 38444. 44159. 57343. 66898. 84804. 81570. 84051. 80943. 99423. 76292. 74498. 4 32505. 24173. 21178. 27883. 35596. 36022. 36351. 36163. 35104. 43210. 39043. 38891. 5 16901. 14206. 9866. 10837. 14755. 16635. 12867. 14725. 13769. 15406. 13635. 13006. 6 5960. 7827. 4604. 4393. 5188. 6555. 5601. 5150. 5237. 5087. 3713. 3093. 7 1996. 3340. 2315. 1754. 1820. 1862. 2433. 2353. 1nl. 1550. 910. 789. 8 64. 1347. 1002. 1019. 712. 697. 715. 1128. 1022. 508. 326. 222. 9 O. 759. 912. 1928. 579. 422. 257. 797. 1239. 831. 242. 103 • Table 5.7.8 VPA. Moray Firth (Functional Unit 9): Males Yield (tonnes),Fbar,Total stock biamass (tannes), spawning stock biomass (tannes), Ln recruitment 1980-1991 • Vear, Yield, Fbar, TSB, SSB, log R 3- 7 1980, 695.5, .3289, 3106.0, 3106.0, 11.31 1981, 1016.3, .7082, 3228.4, 3228.4, 11.61 1982, 574.4, .4448, 2959.2, 2959.2, 11.n 1983, 658.8, .4265, 3611.1, 3611.1, 12.07 1984, 979.0, .5351, 4302.9, 4302.9, 12.25 1985, 1607.8, .6826, 4807.4, 4807.4, 12.17 1986, 1311.0, .5537, 4709.9, 4709.9, 12.23 1987, 1552.0, .6549, 4808.9, 4808.9, 12.28 1988, 1241.2, .6828, 4631.4, 4631.4, 12.03 1989, 1889.6, 1.0585, 4850.2, 4850.2, 11.91 1990, 1298.4, .9430, 3883.9, 3883.9, 11.36 1991, 1052.9, .6627, 3157.6, 3157.6, 6.56 110 Table 5.7.9 VPA. Moray Firth (Functional Unit 9): Females Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 22. 39. 141. 616. 51. 1247. 3430. 1458. 541. 326. 292. 174. 2 1596. 3474. 12585. 7343. 5016. 26592. 61374. 25840. 16047. 15406. 7777. 10352. 3 1909. 2970. 3594. 2237. 2799. 9193. 23416. 8878. 6751. 11576. 5641. n40. 4 3764. 3498. 3809. 2585. 2946. 8613. 18734. 7922. 6333. 12500. 6569. 8300. 5 3001. 3735. 3305. 2627. 2858. 6949. 13263. 5733. 6524. 10617. 5999. 6742. 6 2288. 3348. 2923. 2309. 2355. 5360. 9044. 4301. 5695. 7445. 5266. 4710. 7 1662. 2891. 2505. 2001. 1948. 4174. 6081. 3285. 4916. 4986. 4562. 3196. 8 837. 2231. 1712. 1662. 1660. 3155. 3710. 2321. 4147. 3122. 3563. 2112. 9 678. 1524. 1160. 1127. 1034. 2062. 2497. 1542. 2506. 1746. 2676. 1282. 10 599. 1191. 902. 880. 748. 1558. 1939. 1183. 1754. 1122. 2265. 899. 11 273. 498. 411. 585. 537. 984. 1353. 787. 1125. 850. 1697. 420. 12 244. 462. 378. 535. 491. 886. 1234. 726. 1043. 795. 1565. 386. 13 102. 282. 219. 287. 263. 399. 642. 425. 637. 526. 913. 219. e 14 98. 261. 208. 272. 248. 375. 611: 404. 612. 521. 871. 208. 15 57. 32. 89. 102. 81. 110. 258. 169. 341. 466. 395. 90. 16 144. 141. 302. 431. 264. 342. 860. 683. 1488. 1679. 1573. 283. Tahle 5.7.10 VPA. Moray Firth (Functional Unit 9): Females Mean weight (kg) at 'nominal age' .1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0020 .0020 .0020 .0030 .0020 .0030 .0030 .0030 .0030 .0030 .0030 .0030 2 .0090 .0080 .0070 .0070 .0080 .0070 .0070 .0070 .0070 .0080 .0080 .0080 • 3 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 4 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 .0140 5 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 6 .0190 .0200 .0200 .0200 .0190 .0190 .0190 .0190 .0200 .0190 .0200 .0190 7 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 8 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 9 .0290 .0290 .0290 .0290 .0290 .0290 .0290 .0290 .0290 .0280 .0290 .0290 10 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 11 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 12 .0380 .0380 .0380 .0380 .0380 .0380 .0380 .0380 .0380 .0380 .0380 .0380 13 .0440 .0440 .0440 .0440 .0440 .0440 .0440 .0440 .0440 .0440 .0440 .0440 14 .0440 .0440 .0440 .0440 .•0440 .0440 .0440 .0440 .0440 .0450 .0440 .0440 15 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 .0520 16 .0590 .0610 .0620 .0640 .0620 .0590 .0610 .0630 .0650 .0700 .0630 .0630 111 Iable 5.7.11 VPA. Moray Firth (Functional Unit 9) : Females Fishing mortality (F) at 'nominal age' . 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0002 .0003 .0009 .0036 .0002 .0056 .0187 .0081 .0029 .0019 .0024 .2000 2 .0178 .0369 .1184 .0626 .0400 .1931 .4563 .2122 .1281 .1195 .0626 .1241 3 .0282 .0440 .0514 .0292 .0322 .1011 .2763 .1150 .0831 .1358 .0618 .0863 4 .On5 .0661 .0731 .0474 .0489 .1311 .3063 .1413 .1123 .21n .1063 .1215 5 .0788 .0955 .0822 .0660 .0678 .1556 .3047 .1442 .1656 .2779 .1540 .1515 6 .0701 .1185 .1007 .0759 .orn .1749 .3106 .1525 .2083 .2885 .2160 .1738 7 .0800 .1189 .1221 .0928 .0847 .1917 .3068 .1767 .2608 .2842 .2881 .1970 8 .0652 .1467 .0958 .1112 .1036 .1919 .2602 .1837 .3526 .2628 .33n .2095 9 .0815 .1620 .1059 .0842 .0936 .1809 .2287 .1639 .3083 .2456 .3nO .1948 10 .1464 .2006 .1360 .1091 .0739 .1989 .2581 .1611 .2836 .2203 .5m .2087 11 .1069 .1742 .0984 .1227 .0899 .1315 .2655 .1579 .2267 .2159 .6026 .1961 12 .1552 .2646 .1943 .1794 .1435 .2097 .2418 .2223 .3234 .2480 .n09 .2627 13 .1028 .2694 .1934 .2215 .1256 .1663 .2315 .1224 .3098 .2687 .4994 .2233 14 .5184 .4110 .3271 .3890 .3025 .2652 .4110 .2231 .2599 .4501 .9568 .2000 15 .2583 .3145 .2379 .2631 .1904 .2136 .2946 .1892 .2976 .3222 .7422 .2286 16 .2583 .3145 .2379 .2631 .1904 .2136 .2946 .1892 .2976 .3222 .7422 .2286 Iable 5.7.12 VPA. Moray Firth (Functional Unit 9): Females Population numbers (OOO's) at 'nominal age' . 1980-1991 • Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 149591. 175620. 189057. 200465. 235489. 260239. 214041. 209525. 213734. 200464. 138555. 1102. 2 104463. 110801. 130069. 139936. 147978. 174411. 191717. 155613. 153965. 157873. 148226. 102393. 3 75679. 76015. 79107. 85598. 97380. 105328. 106513. 89984. 93239. 100343. 103784. 103151. 4 59322. 60233. 59555. 61524. 68057. n196. n945. 66150. 65668. 70248. 71721. 79880. 5 43610. 45173. 46159. 45323. 48038. 53062. 55439. 46978. 47020. 48054. 46263. 52796. 6 3n19. 32998. 33617. 34810. 34738. 36751. 37182. 33469. 33296. 32620. 29797. 32471. 7 23809. 28408. 23998. 24887. 26417. 26316. 25262. 22314. 23527. 22134. 20014. 19656. 8 14614. 17995. 20652. 17390. 18571. 19872. 1n87. 15217. 15310. 14840. 13639. 12285. 9 9547. 11209. 12722. 15364. 12739. 13708. 13429. 11226. 10368. 8810. 9342. 7966. 10 4844. 7204. 7805. 9370. 11563. 9498. 9366. 8747. 7802. 6237. 5643. 5246. 11 2965. 3426. 4826. 55n. 6878. 8792. 6374. 5924. 6096. 4811. 4097. 2593. 12 1870. 2181. 2356. 3581. 4039. 5147. 6312. 4002. 4142. 3979. 3174. 1836. 13 1151. 1311. 1371. 1588. 2451. 2865. 3417. 4058. 2623. 2454. 2542. 1202. 14 266. 850. 820. 925. 1042. 1no. 1986. 2220. 2939. 1575. 1536. 1263. 15 273. 130. 461. 484. 513. 631. 1111. 1078. 1454. 1856. 822. 483. 16 694. 571. 1566. 2046. 16n. 1953. 3698. 4358. 6347. 6689. 3273. 1520. Iable 5.7.13 VPA. Moray Firth (Functional Unit 9): Females Yield (tonnes),Fbar,Iotal stock biomass (tonnes) , spawning stock biomass (tonnes) , Ln rccruitment 1980-1991 Year, Yield, Fbar, TSB, SSB, log R 3·10 1980, 318.8, .On9, 5979.9, 4740.5, 11.92 1981, 512.8, .1190, 6332.6, 5094.9, 12.08 1982, 528.8, .0959, 6611.0, 5322.4, 12.15 1983, 451.5, .0770, 7195.4, 5614.4, 12.21 1984, 426.3, .on8, 7639.7, 5984.9, 12.37 1985, 1043.5, .1657, 8501.7, 6500.1, 12.47 1986, 1937.8, .2815, 8590.7, 6606.6, 12.27 1987, 932.0, .1548, 7529.7, 5811.8, 12.25 1988, 1095.3, .2218, n03.2, 5984.3, 12.27 1989, 1273.0, .2416, 7773.9, 5909.5, 12.21 1990, 1085.7, .2648, 7070.9, 5469.4, 11.84 1991, 750.5, .1679, 6130.5, 5308.0, 7.01 112 Table 5.7.14 Noup (Functional Unit 10) : landings (in ton- nes), by gear,1982-91, all UK Year Nephrops Trawl Other Trawl Total 1982 12 7 19 83 9 6 15 84 75 36 111 85 2 20 22 86 46 22 68 1987 12 32 44 88 23 53 76 89 24 61 85 90 101 116 217 91 (* ) 110 86 196 (*)provisional Table 5.7.15 Noup (Functional Unit 10) : landings (in ton nes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig trawls combined (see Table 6.4 ) Year Landings Effort LPUE 1982 11.6 0.5 24.7 83 9.2 0.3 30.7 84 75.3 2.0 36.9 85 1.5 < 0.1 25.0 86 45.7 0.7 62.6 1987 12.3 0.7 18.1 88 23.3 1.0 34.3 89 23.7 0.9 25.8 90 101.0 2.9 34.6 91 (*) 110.0 4.8 23.1 (*) provisional 113 Table 5.7.16 Nephrops landings (tannes by Functional Unit plus other rectangles in Management Area (IVa 44-48 E6-E7 + 44E8) (Area F) Year FU9 FU10 Other rectangles Total 1982 1120 19 1 1140 1983 940 15 1 956 1984 1170 111 3 1284 1985 2081 22 15 2118 1986 2143 68 44 2255 1987 1991 44 30 2065 1988 1959 76 45 2080 1989 2576 85 44 2705 1990 2038 217 69 2324 1991 1517 196 65 1778 Table 5.7.17 Total Nephrops landings (t) by country in Management Area (IVa 44-48 E6-E7 + 44E8) - (Area F) Year UK TOTAL 1982 1140 1140 1983 956 956 1984 1284 1284 1985 2118 2118 1986 2255 2255 1987 2065 2065 1988 2080 2080 1989 2705 2705 1990 2324 2324 • 1991 1778 1778 114 Table 5.8.1 Fladen (Functional Unit 7) : landings (in tan nes), by country, 1982-91, all gears Year UK Denmark Belgium Total 1982 422 ? ? ~ 422 83 693 ? ? ~ 693 84 649 ? ? ~ 649 85 1 141 7 ? 1 148 86 1 493 50 0 1 543 1987 1 398 323 0 1 721 88 1 493 81 0 1 574 89 2 133 230 0 2 363 90 2 302 290 2 2 594 91 (-) 3 796 445 0 4 241 (.) provisional Table 5.8.2- Fladen (Functional Unit 7) : landings (in tan nes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig trawls combined (see Table 6.4 ) Year Landings Effort LPUE 1982 382 12.2 31.3 83 548 15.4 35.5 84 549 11. 4 48.2 85 1 016 26.6 38.2 86 1 398 37.8 37.0 1987 1 024 41.6 24.6 88 1 306 41. 7 31.3 89 1 719 47.1 36.5 90 1 703 43.4 39.2 91 3 024 78.5 38.5 (.) provisional Table 5.8.3 Fladen (Functional Unit 7) : mean sizes (CL in mm) of male and female Nephrops in Scottish landings, 1982-91 Year Males Females 1982 39.5 32.7 83 36.2 30.9 84 30.2 28.6 85 35.2 31.6 86 31.3 28.7 1987 31.5 29.5 88 30.0 29.4 89 33.6 31.5 90 32.6 29.4 91 34.2 31. 9 115 Table 5.8.4 VPA. Fladen Ground (Functional Unit 7): Males Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 2815. 1167. 1664. 3387. 3030. 2776. 4969. 5044. 7955. 6469. 7027. 15111. 2 7800. 3276. 3432. 7648. 10396. 9721. 21702. 19186. 22110. 19563. 19639. 43543. 3 4578. 4038. 1794. 2883. 4049. 10296. 10301. 14577. 10143. 18385. 19541. 45122. 4 1661. 2691. 2029. 2670. 1355. 6703. 4012. 6088. 4336. 12540. 13854. 25715. 5 256. 1401. 1454. 2009. 339. 2562. 1555. 1137. 1675. 6949. 5172. 9860. 6 27. 372. 851. 1044. 83. 1187. 766. 253. 370. 1828. 1928. 2828. 7 1. 102. 572. 335. 30. 754. 516. 73. 102. 293. 706. 918. 8 O. 32. 665. 106. 29. 1352. 754. 37. 107. 149. 845. 665. Table 5.8.5 VPA. Fladen Ground (Functional Unit 7): Males Mean weight (kg) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0070 .0070 .0070 .0070 .0070 .0070 .0080 .0080 .0080 .0070 .0070 2 .0140 .0130 .0130 .0130 .0130 .0140 .0140 .0140 .0130 .0140 .0130 :~ 3 .0240 .0260 .0260 .0260 .0240 .0250 .0240 .0250 .0240 .0250 .0260 .0251 4 .0370 .0390 .0390 .0390 .0370 .0390 .0380 .0370 .0380 .0390 .0380 .0381 5 .0510 .0530 .0540 .0540 .0530 .0530 .0530 .0520 .0530 .0530 .0530 .0531 6 .0660 .0680 .0700 .0700 .0690 .0700 .0700 .0690 .0680 .0680 .0690 .0691 7 .0840 .0860 .0870 .0850 .0870 .0890 .0880 .0860 .0850 .0870 .0870 .0871 8 .0000 .1000 .1020 .1030 .1010 .1020 .1010 .1010 .1070 .1000 .1030 .1011 116 Table 5.8.6 VPA. Fladen Ground (Functional Unit 7): Males Fishing mortality (F) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .1053 .0441 .0387 .0645 .0434 .0264 .0453 .0363 .0544 .0415 .0584 .2000 2 .3328 .1913 .1963 .2792 .3209 .2124 .3281 .2750 .2455 .2044 .1901 .6834 3 .3900 .3230 .1695 .2816 .2616 .6955 .4107 .4327 .2561 .3730 .3634 1.0120 4 .2937 .4744 .2994 .4597 .2314 1.0657 .7502 .51n .2464 .6586 .6109 1.4233 5 .(·820 .4893 .5828 .6213 .1063 1.0548 .9109 .5612 .2919 .9035 .7300 1.5675 6 .0618 .1834 .n19 1.3947 .0502 .7388 1.3824 .4022 .4032 .6829 .8015 1.5106 7 .1459 .3824 .5347 .8252 .1293 .9531 1.0145 .4937 .3138 .7483 .7141 1.5004 8 .1459 .3824 .5347 .8252 .1293 .9531 1.0145 .4937 .3138 .7483 .7141 1.5004 Table 5.8.7 VPA. Fladen Ground (Functional Unit 7): Males Population numbers (OOO's) at 'nominal age'. 1980-1991 e Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 32505. 31284. 50644. 62623. 82472. 123446. 129583. 163572. 173675. 183887. 143233. 96013. 2 31630. 21673. 22176. 36092. 43492. 58501. 89072. 91742. 116856. 121849. 130685. 100093. 3 16248. 16798. 13260. 13500. 20225. 23376. 35047. 47526. 51624. 6n25. 735n. 80053. 4 7499. 8149. 9009. 8292. 7546. 11533. 8638. 17219. 22840. 29601. 34551. 37900. 5 3750. 4142. 3756. 4947. 3879. 4435. 2943. 3022. 7601. 13225. 11350. 13894. 6 528. 2559. 1881. 1554. 1969. 2584. 1144. 8n. 12n. 4205. 3969. 4052. 7 8. 368. 1578. 6n. 285. 1387. 914. 213. 434. 632. 1574. 1319. 8 O. 117. 1834. 214. 2n. 2488. 1336. 107. 455. 321. 1883. 956. _able 5.8.8 VPA. Fladen Ground (Functional Unit 7): Males Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1980-1991 Year, Yield, Fbar, TSB, SSB, log R 3- 6 1980, 315.1, .2069, 1564.5, 1564.5, 10.39 1981, 372.3, .3675, 1692.1, 1692.1, 10.35 1982, 445.8, .4434, 1997.9, 1997.9, 10.83 1983, 523.5, .6893, 2037.4, 2037.4, 11.04 1984, 333.4, .1624, 2301.5, 2301.5, 11.32 1985, 1115.2, .8887, 3510.5, 3510.5, 11.n 1986, 1019.4, .8636, 3904.6, 3904.6, ".n 1987, 985.5, .4784, 4665.0, 4665.0, 12.01 1988, 893.3, .2994, 5590.7, 5590.7, 12.06 1989, 1801.8, .6545, 6914.6, 6914.6, 12.12 1990, 1905.6, .6265, 7133.8, 7133.8, 1'.87 1991, 3693.4, 1.3783, 6742.2, 6742.2, 11.47 117 Table 5.8.9 VPA. Fladen Ground (Functional Unit 7): Females Catch (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 1756. 745. 1070. 2249. 1907. 1548. 4103. 2884. 2898. 2924. 4285. 8511. 2 3328. 1327. 1806. 3837. 4475. 2837. 12299. 6680. 7407. 6901. 10295. 15704. 3 3355. 1016. 1191. 2590. 5423. 2220. 16069. 7391. 8151. 6747. 13712. 15284. 4 1967. 639. 459. 11n. 4096. 2182. 10776. 4906. 5453. 6444. 12307. 15124. 5 824. 408. 304. 956. 1666. 2316. 4975. 3329. 2824. 3900. 7803. 11032. 6 341. 231. 247. 585. 782. 1904. 2760. 2019. 1892. 2871. 4102. 5771. 7 152. 140. 190. 307. 401. 759. 1700. 934. 1121. 2080. 2763. 3413. 8 64. 78. 109. 175. 187. 198. 1175. 581. 705. 1578. 1850. 2432. 9 30. 57. 41. 127. 91. 10. 600. 268. 442. 1408. 1342. 1640. 10 16. 13. 26. 62. 24. 2. 272. 67. 317. 513. 710. 683. 11 9. 8. 28. 47. 16. 4. 215. 44. 178. 335. 472. 464. 12 3. 5. 29. 35. 10. 5. 174. 29. 64. 206. 287. 301. 13 5. 13. 19. 33. 19. 9. 437. 61. 117. 298. 629. 808.e Table 5.8.10 VPA. Fladen Ground (Functional Unit 7): Females Mean weight (kg) at 'nominal age' .1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0050 .0050 .0050 .0050 .0050 .0050 .0050 .0050 .0050 .0050 .0050 .0050 e 2 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 3 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 .0110 4 .0140 .0140 .0140 .0140 .0140 .0150 .0140 .0140 .0140 .0150 .0140 .0150 5 .0180 .0180 .0180 .0180 .0180 .0190 .0180 .0180 .0180 .0180 .0180 .0180 6 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 7 .0260 .0260 .0260 .0260 .0260 .0250 .0260 .0260 .0260 .0260 .0260 .0260 8 .0300 .0300 .0300 .0300 .0300 .0290 .0300 .0300 .0300 .0300 .0300 .0300 9 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 .0340 10 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 .0390 11 .0400 .0410 .0420 .0420 .0410 .0430 .0420 .0410 .0400 .0410 .0410 .0410 12 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 .0450 13 .0510 .0520 .0540 .0510 .0560 .0520 .0600 .0540 .0610 .0540 .0560 .0550 118 Table 5.8.11 VPA. Fladen Ground (Functional Unit 7): Females · FIshing mortality (F) at 'nominal agc'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0353 .0113 .0128 .0224 .0184 .0151 .0376 .0221 .0229 .0286 .0405 .2000 2 .1143 .0356 .0361 .0611 .0597 .0363 .1686 .0837 .0766 .0735 .1408 .2162 3 .2151 .0463 .0405 .0665 .1150 .0380 .2936 .1448 .1392 .0928 .2041 .3192 4 .2800 .0576 .0265 .0509 .1424 .0618 .2599 .1365 .1513 .1557 .2433 .3626 5 .1841 .0856 .0350 .0706 .0950 .1118 .1950 .1191 .1085 .1540 .2858 .3582 6 .0985 .0719 .0684 .0876 .0760 .1496 .1886 .1130 .0919 .1535 .2402 .3546 7 .0414 .0534 .on8 .1137 .0796 .0982 .1934 .0899 .0846 .1383 .2166 .3223 8 .0674 .0270 .0533 .0956 .0937 .0513 .2166 .0935 .0906 .1645 .1755 .3006 9 .0317 .0787 .0176 .0814 .0658 .0062 .2163 .0698 .0955 .2626 .2053 .2327 10 .0128 .0168 .0474 .0333 .0197 .0021 .2412 .0334 .1105 .1529 .2047 .1529 11 .0433 .0083 .0456 .1112 .0106 .0037 .2731 .0553 .1173 .1634 .2054 .2000 12 .0291 . .0345 .0368 .0752 .0320 .0040 .2433 .0528 .10n .1929 .2050 .1951 13 .0291 .0345 .0368 .0752 .0320 .0040 .2433 .0528 .10n .1929 .2050 .1951 eTable 5.8.12 VPA. Fladen Ground (Functional Unit 7): Females Population numbers (OOO's) at 'nominal age'. 1980-1991 Age 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 58590. 76669. 97602. 117474. 120784. 119537. 128535. 152721. 148303. 119879. 124826. 54075. 2 33927. 41900. 56157. 71384. 85091. 87837. 87223. 91706. 110656. 107371. 86302. 88803. 3 19056. 24n6. 33104. 44343. 54982. 65628. 69348. 60333. 69057. 83915. 81682. 61380. 4 8845. 12582. 19368. 26026. 33968. 40126. 51723. 42331. 42736. 49193. 62618. 54531. 5 5390. 5473. 9725. 15442. 20250. 24120. 30883. 32655. 30236. 30076. 34470. 40194. 6 4003. 3671. 4113. 7687. 11780. 150n. 17659. 20805. 23735. 22209. 21110. 21206. 7 4121. 2970. 2797. 3145. 5766. 8939. 10629. 11973. 15213. ln26. 15596. 13592. 8 1078. 3237. 2305. 2119. 2298. 4359. 6635. 7172. 8960. 11445. 12639. 10282. 9 1076. 825. 2579. 1789. 1576. 1713. 3391. 4374. 5348. 6700. 7949. 8682. 10 1364. 853. 624. 2075. 1350. 1208. 1394. 2236. 3340. 3980. 4219. 5300. 11 224. 1103. 687. 488. 1643. 1084. 987. 897. lnl. 2448. 2796. 2815. 12 115. 175. 895. 537. 357. 1331. 884. 615. 695. 1289. 1702. 1864. 13 207. 412. 568. 508. 676. 2385. 2223. 1316. 1258. 1869. 3732. 5014. e Table 5.8.13 VPA. Fladen Ground (Functional Unit 7): Females Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes) , Ln recruitment 1980-1991 Year, Yietd, Fbar, TSB, SSB, log R 3- 8 1980, 130.4, .1478, 1336.9, 1043.9, 10.98 1981, 56.5, .0570, 1656.7, 1273.4, 11.25 1982, 64.3, .0502, 2191.9, 1703.8, 11.49 1983, 142.1, .0808, 2815.3, 2228.0, 11.67 1984, 231.7, .1003, 3435.1, 2831.2, 11.70 1985, 199.4, .0851, 4100.0, 3502.3, 11.69 1986, 750.3, .2245, 4631.5, 3988.8, 11.76 1987, 382.0, .1161, 4697.0, 3933.4, 11.94 1988, 427.0, .1110, 5206.4, 4464.8, 11.91 1989, 582.5, .1431, 5595.9, 4996.5, 11.69 1990, 925.8, .2276, 5794.3, 5170.1, 11.73 1991, 1209.8, .3363, 5302.8, 5032.4, 10.90 119 Table 5.8.14 Nephrops landings (tonnes) by Functional Unit plus other rectangles in Management Area IVa Remainder - (Area G) Year FU7 Other rectangles Total 1982 ~ 422 ~ 1 ~ 423 1983 ~ 693 ~10 ~ 703 1984 ~ 649 ~ 8 ~ 657 1985 1148 ~34 ~1182 1986 1543 ~17 ~1560 1987 1721 ~13 ~1734 1988 1574 54 1628 1989 2363 66 2429 1990 2594 79 2673 1991 4241 135 4376 Table 5.8.15 Total Nephrops landings (t) by country in Management Area IVa Remainder - (Area G) Year UK Denmark Belgium TOTAL 1982 423 ? ? 423 1983 703 ? ? 703 1984 657 ? ? 657 1985 1182 ? ? 1182 1986 1510 50 0 1560 1987 1411 323 0 1734 1988 1501 127 0 1628 1989 2154 275 0 2429 1990 2318 353 1.9 2673 1991 3848 528 0 4376 120 Table 5.9.1 Botney Gut - Silver Pit (Functional Unit 5) landings (in tonnes), by country, 1982-91 Year Belgium Denmark UK Total 1982 457(t) ? o ~ 457 83 633(t) ? 3 ~ 636 84 612(t) ? 1 ~ 613 85 680(t) ? < 1 ~ 680 86 378 ? 4 ~ 382 1987 427 ? 6 ~ 433 88 483 59 4 546 89 554 90 1 645 90 585 161 1 747 91(-) 573 184 2 759 (-) provisional • (t) data are for sub areas IVb and c, assumed Botney Gut/Silver Pit Table 5.9.2 Botney Gut - Silver Pit (Functional Unit 5) landings (in tonnes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Belgian Nephrops trawlers, 1982-91 Year Landings Effort LPUE apparent revised 1982 449(t) 39.0 11. 5 83 628(t) 38.6 16.3 84 597(t) 53.8 11. 1 85 669(t) 62.2 10.8 86 378 53.6 7.1 1987 427 52.3 8.2 88 481 57.9 8.3 89 552 63.6 8.7 90 573 72.9 7.9 9.3(:1:) • 91 (-) 550 85.3 6.7 7.4(:1:) (-) provisional (t) data are for sub areas IVb and c, assumed Botney Gut/Silver Pit (:I:) correction for allocation of effort during 4th quarter(see section 5.9.1 Landings,effort LPUE). 121 Table 5.9.3 LCA. Botney Gut/Silver Pit (Functional Unit 5): Males Cohort Analysis Output. Reference period 1986-1991 LABEL = BG-92-MA-11 6YR cOHORT ANALYSIS L INFINITY = 62.0000 K = .1650 cOHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REHOVALS M OT FOT F Z NO. ATTAINING AVE • NO. IN SEA BIOMASS kg 24.0 51.8 •3000 .3277 .0014 .0042 .3042 39864.8 12433.0 128072.0 26.0 340.8 .3000 .3464 .0100 .0289 .3289 36083.1 11814.0 156214.6 28.0 1018.3 .3000 .3674 .0340 .0925 .3925 32198.0 11016.8 183684.3 30.0 1943.8 .3000 .3911 .0768 .1964 .4964 27873.8 9909.5 205137.5 32.0 2000.5 .3000 .4181 .0974 .2329 .5329 22954.7 8604.1 218170.2 34.0 1307.3 .3000 .4491 .0792 .1763 .4763 18369.6 7427.7 227961.6 36.0 1378.5 .3000 .4851 .1053 .2171 .5171 14831.9 6363.6 233889.6 38.0 1298.8 .3000 .5273 .1299 .2463 .5463 11541.3 5288.0 230559.8 40.0 1102.0 .3000 .5776 .1495 .2589 .5589 8652.6 4271.6 219051.2 42.0 908.0 .3000 .6385 .1737 .2721 .5721 6265.4 3351.4 200585.4 44.0 630.0 .3000 .7138 .1759 .2464 .5464 4348.0 2570.1 178272._ 46.0 483.0 .3000 .8093 .2049 .2532 .5532 2943.8 1920.5 153402.9 48.0 343.0 .3000 .9342 .2354 .2519 .5519 1881.5 1373.4 125579.1 50.0 228.0 .3000 1.1050 .2738 .2478 .5478 1123.4 931.3 96956.2 52.0 129.0 .3000 1.3524 .2979 .2203 .5203 613.3 595.5 70242.5 54.0 68.0 .3000 1.7435 .3440 .1973 .4973 303.4 353.8 47059.1 56.0 51.0 .3000 .2000 .5000 127.5 353.8 52841.5 Table 5.9.4 LCA. Botney Gut/Silver Pit (Functional Unit 5): Females Cohort Analysis Output. Reference period 1986-1991 LABEL =BG-92-FE-11 6YR CO HORT ANALYSIS • L INFINlTY = 60.0000 K = .0800 cOHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REMOVALS M OT FOT FZ NO. ATTAINING AVE. NO. IN SEA BIOMASS kg 24.0 89.5 .2000 .7145 .0028 .0039 .2039 34602.7 23006.5 267710.6 26.0 274.0 .2000 .7578 .0099 .0131 .2131 29911.8 20931.8 302493.2 28.0 839.5 .2000 .8067 .0364 .0451 .2451 25451.2 18629.5 329214.6 30.0 1273.8 .2000 .8624 .0688 .0798 .2798 20884.4 16002.8 341202.6 32.0 1043.0 .2000 .9264 .0723 .0780 .2780 16407.3 13399.3 340672.9 34.0 721.3 .2000 1.0005 .0649 .0649 .2649 12681.8 11146.3 334446.2 36.0 834.3 .2000 1.0876 .1005 .0924 .2924 9729.3 9064.4 318035.0 38.0 883.3 .2000 1.1914 .1515 .1271 .3271 7079.0 6984.4 284204.4 40.0 618.0 .2000 1.3170 .1591 .1208 .3208 4794.1 5149.7 241226.0 42.0 503.0 .2000 1.4723 .2051 .1393 .3393 3142.2 3641.2 195037.7 44.0 248.0 .2000 1.6691 .1669 .1000 .3000 1906.6 2503.5 152407.6 46.0 178.0 .2000 1.9269 .2067 .1073 .3073 1155.6 1680.4 115618.6 48.0 100.0 .2000 2.2790 .2188 .0960 .2960 639.2 1059.5 81976.9 50.0 40.0 .2000 2.7893 .1772 .0635 .2635 325.6 643.1 55691.4 52.0 23.0 .2000 3.5960 .2371 .0659 .2659 156.1 361.5 34879.4 54.0 20.0 .2000 .1000 .3000 60.0 361.5 38713.0 122 Table 5.9.5 LCA. Botney Gut/Silver Pit (Functional Unit 5): Males Cohort Analysis Output. Reference period 1986-1988 lABEL = BG-92-MA-21 3YR A COHORT ANALYSIS l INFINITY = 62.0000 J( = .1650 COHORT ANALYSIS BY POPE'S APPROXIMATION SIZE HH REHOVALS H OT FOT F Z NO. ATTAINING AVE • NO. IN SEA BIOHASS leg 24.0 32.0 .3000 •3277 .0010 .0030 .3030 33671.4 10503.3 108194.4 26.0 216.0 .3000 .3464 .0075 .0216 .3216 30488.4 9994.5 132156.0 28.0 827.3 .3000 .3674 .0326 .0887 .3887 27274.0 9338.4 155700.9 30.0 1473.0 .3000 .3911 .0683 .1747 .4747 23644.5 8440.5 174727.5 32.0 1373.5 .3000 .4181 .0774 .1851 .4851 19637.5 7432.0 188451.3 34.0 1059.3 .3000 .4491 .0733 .1632 .4632 16032.4 6501.1 199523.0 36.0 1081.3 .3000 .4851 ~0935 .1928 .4928 13021.2 5618.3 206497.4 38.0 1094.8 .3000 .5273 .1228 .2329 .5329 10252.2 4713.2 205497.5 40.0 1021.0 .3000 .5776 .1553 .2689 .5689 7740.6 3810.9 195429.3 42.0 806.0 .3000 .6385 .1734 .2715 .5715 5572.8 2981.5 178443.5 44.0 599.0 .3000 .7138 .1891 .2650 .5650 3868.9 2272.7 157646.0 .46.0 448.0 .3000 .8093 .2178 .2691 .5691 2584.9 1676.3 133897.4 48.0 340.0 .3000 .9342 .2742 .2935 .5935 1630.9 1169.6 106944.6 50.0 209.0 .3000 1.1050 .3056 .2766 .5766 936.7 765.5 79696.2 52.0 113.0 .3000 1.3524 .3277 .2423 .5423 495.3 474.7 55994.6 54.0 63.0 .3000 1.7435 .4216 .2418 .5418 237.9 268.4 35696.4 56.0 37.0 .3000 .2000 .5000 92.5 268.4 40082.5 Table 5.9.6 LCA. Botney Gut/Silver Pit (Functional Unit 5): Males Cohort Analysis Output. Reference period 1989-1991 lABEL = BG-92-MA'31 3YR B ~OHORT ANALYSIS l INFINITY = 62.0000 J( = .1650 COHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REMOVALS H OT FOT F Z NO. ATTAINING AVE • NO. IN SEA BIOHASS leg 24.0 71.5 .3000 •3277 .0016 .0050 .3050 46026.4 14352.8 147847.6 26.0 465.5 .3000 .3464 .0118 .0342 .3342 41649.0 13624.0 180148.0 28.0 1210.3 .3000 .3674 .0351 .0955 .3955 37096.0 12685.9 211514.0 30.0 2414.5 .3000 .3911 .0832 .2127 .5127 32079.0 11369.5 235360.8 32.0 2625.8 .3000 .4181 .1126 .2693 .5693 26250.3 9767.6 247673.1 34.0 1555.3 .3000 .4491 .0838 .1866 .4866 20689.5 8347.1 256175.6 36.0 1676.8 .3000 .4851 .1148 .2366 .5366 16627.5 7101.7 261016.9 38.0 1502.0 .3000 .5273 .1356 .2572 .5572 12816.4 5856.2 255330.7 40.0 1183.0 .3000 .5776 .1451 .2511 .5511 9553.3 4726.2 242364.9 42.0 1010.0 .3000 .6385 .1743 .2730 .5730 6948.5 3715.8 222396.5 44.0 660.0 .3000 .7138 .1654 .2317 .5317 4819.4 2862.7 198570.7 46.0 518.0 .3000 .8093 .1953 .2413 .5413 3297.4 2160.8 172593.0 48.0 346.0 .3000 .9342 .2071 .2217 .5217 2127.8 1573.4 143872.3 50.0 248.0 .3000 1.1050 .2536 .2295 .5295 1307.0 1093.3 113828.7 52.0 146.0 .3000 1.3524 .2819 .2084 .5084 728.1 712.0 83984.3 54.0 74.0 .3000 1.7435 .3046 .1747 .4747 366.1 434.1 57742.8 56.0 64.0 .3000 .2000 .5000 160.0 434.1 64R37.R 123 Table 5.9.7 LCA. Botney Gut/Silver Pit (Functional Unit 5): Females Cohort Analysis Output. Reference period 1986-1988 lABEL = BG-92-FE·21 3YR-A COHORT ANALYSIS l INFINITY = 60.0000 K = .0800 COHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REMOVALS M OT FOT FZ NO. ATTAINING AVE. NO. IN SEA BIOHASS kg 24.0 62.3 .2000 .7145 .0034 .0047 .2047 19849.6 13193.7 153526.2 26.0 200.8 .2000 .7578 .0127 .0168 .2168 17148.6 11984.1 173186.3 28.0 664.3 .2000 .8067 .0508 .0629 .2629 14550.8 105n.3 186917.4 30.0 1340.8 .2000 .8624 .1326 .1537 .3537 11769.9 8748.3 186526.5 32.0 1144.5 .2000 .9264 .1563 .1688 .3688 8675.3 6807.5 173078.4 34.0 662.0 .2000 1.0005 .1263 .1263 .3263 6164.9 5262.5 157903.0 36.0 583.0 .2000 1.0876 .1580 .1453 .3453 4447.9 4033.2 141507.7 38.0 470.8 .2000 1.1914 .1906 .1600 .3600 3055.4 2960.1 120449.4 40.0 319.8 .2000 1.3170 .2025 .1538 .3538 1989.7 2094.8 98124.3 42.0 178.0 .2000 1.4723 .1805 .1226 .3226 1248.7 1463.5 78389.2 44.0 113.0 .2000 1.6691 .1887 .1130 .3130 n6.6 1009.6 61460._ 46.0 49.0 .2000 1.9269 .1381 .0717 .2717 460.5 690.8 47533 • 48.0 33.0 .2000 2.2790 .1648 .0723 •2723 272.8 463.3 35843.6 50.0 15.0 .2000 2.7893 .1452 .0521 .2521 146.7 293.8 25445.2 52.0 12.0 .2000 3.5960 .2702 .0751 .2751 72.6 165.8 15999.8 54.0 9.0 .2000 .1000 .3000 27.0 165.8 17758.4 Table 5.9.8 LCA. Botney Gut/Silver Pit (Functional Unit 5): Females Cohort Analysis Output. Reference period 1989-1991 lABEL = BG-92-FE-31 3YR-B COHORT ANALYSIS • l INFINITY = 60.0000 K = .0800 CO HORT ANALYSIS BY POPE'S APPROXIMATION SIZE HM REMOVALS H OT FOT FZ NO. ATTAINING AVE. NO. IN SEA BIOHASS kg 24.0 117.8 .2000 .7145 .0026 .0036 .2036 49160.0 32688.6 380374.4 26.0 349.0 .2000 .7578 .0089 .0117 .2117 42504.5 29758.8 430056.3 28.0 1014.5 .2000 .8067 .0308 .0382 .2382 36203.3 26571.2 469556.9 30.0 1205.0 .2000 .8624 .0450 .0521 .2521 29873.0 23154.2 493680.3 32.0 942.5 .2000 .9264 .0440 .0475 .2475 24034.9 19897.1 505875.3 34.0 779.8 .2000 1.0005 .0461 .0461 .2461 19111.0 16948.8 508550.7 36.0 1083.8 .2000 1.0876 .0843 .0775 .2775 14939.6 14025.7 492106.6 38.0 1296.8 .2000 1.1914 .1418 .1191 .3191 11046.9 10948.7 445512.9 40.0 918.0 .2000 1.3170 .1492 .1133 .3133 7553.7 8151.2 381824.8 42.0 828.0 .2000 1.4723 .2130 .1447 .3447 4999.8 5n2.9 309220.7 44.0 383.0 .2000 1.6691 .1629 .0976 .2976 3009.9 3959.4 241037.3 46.0 307.0 .2000 1.9269 .2272 .1179 .3179 1831.5 2638.8 181564.5 48.0 167.0 .2000 2.2790 .2374 .1042 .3042 992.6 1631.7 126246.5 50.0 65.0 .2000 2.7893 .1901 .0682 .2682 496.3 974.7 84401.9 52.0 35.0 .2000 3.5960 .2401 .0668 .2668 234.9 543.1 52411. 7 54.0 30.0 .2000 .1000 .3000 90.0 543.1 58172.2 124 Table 5.9.9 VPA. Botney Gut- Silver Pit (Functional Unit 5): Males Catch (000'5) at 'nominal age'. 1986-1991 Age 1986 1987 1988 1989 1990 1991 1 1058. 1457. 1935. 1708. 1612. 3578. 2 3044. 3277. 3236. 2870. 4610. 7423. 3 2020. 2276. 2231. 2226. 3202. 3690. 4 164,. 150,. 1926. 1768. 2071. 1967. 5 844. 897. 1185. 1143. 1121. 868. 6 469. 509. 703. 639. 711. 440. 7 292. 252. 438. 376. 368. 233. 8 126. 167. 243. 251. 183. 158. 9 63. 68. 132. 127. 110. 77. 10 34. 44. 63. 60. 5,. 56. 11 16. 40. 44. 52. 37. 21. 12 14. 14 • 17. 24. 14. 16. • 13 7. 41. 22. 60. 42. 30. Males Table 5.9.10 VPA. Botney Gut- Silver Pit (Functional Unit 5): Mean weight (kg) at 'nominal age'. 1986-1991 Age 1986 1987 1988 1989 1990 1991 1 .0170 .0170 .0170 .0170 .0170 .0170 2 .0250 .0250 .0250 .0250 .0250 .0250 • 3 .0380 .0380 .0390 .0380 .0380 .0380 4 .0520 .0510 .0520 .0520 .0520 .0510 5 .0650 .0660 .0660 .0650 .0650 .0660 6 .0800 .0800 .0800 .0790 .0790 .0790 7 .0930 .0930 .0920 .0930 .0920 .0930 8 .1050 .1050 .1050 .1050 .1040 .1050 9 .1160 .1170 .1170 .1170 .1170 .1170 10 .1270 .1260 .1260 .1260 .1250 .1270 11 .1360 .1360 .1360 .1360 .1360 .1350 12 .1450 .1450 .1450 .1450 .1450 .1450 13 .1580 .1630 .1600 .1620 .1610 .1670 125 Table 5.9.11 VPA. Botney Gut- Silver Pit (Functional Unit 5): Males Fishing mortality (F) at 'nominal age'. 1986-1991 Äge 1986 1987 1988 1989 1990 1991 1 .0499 .0716 .0919 .0687 .0504 .2000 2 .1963 .2391 .2506 .2134 .2979 .3835 3 .2119 .2466 .2851 .3066 .4406 .4675 4 .2888 .2697 .3833 .4331 .5931 .6108 5 .2365 .2838 .3989 .4675 .6193 .6122 6 .2343 .2448 .4248 .4405 .6887 .6063 7 .2661 .2129 .3874 .4799 .5597 .5796 8 .2341 .2684 .3678 .4544 .5175 .5703 9 .1894 .2126 .3968 .3n6 .4150 .4885 10 .1999 .2167 .3473 .3541 .2843 .4413 11 .1896 .4378 .3934 .6140 .4363 .2000 12 .1929 .2890 .3791 .4485 .3786 .3766 13 .1929 .2890 .3791 .4485 .3786 .3766 Table 5.9.12 VPA. Botney Gut- Silver Pit (Functional Unit 5) : Males Population numbers (OOO's) at 'nominal age'. 1986-1991 • Äge 1986 1987 1988 1989 1990 1991 1 25150. 24354. 25444. 29728. 37934. 22733. 2 19676. 17725. 16795. 17194. 20561. 26n2. 3 12180. 11979. 10338. 9684. 10290. 11308. 4 7519. 7300. 6935. 5759. 5280. 4906. 5 4613. 4173. 4130. 3502. 2767. 2161. 6 2582. 2698. 2327. 2053. 1625. 1103. 7 1439. 1513. 1565. 1127. 979. 605. 8 696. 817. 906. 787. 517. 414. 9 419. 408. 463. 465. 370. 228. 10 213. 257. 244. 230. 236. 181. 11 106. 129. 153. 128. 120. 132. 12 92. 65. 62. 77. 51. 57. 13 44. 185. 81. 191. 153. 110. Botney Gut- Silver Pit (Functional Unit 5): Males • Table 5.9.13 VPA. Yield (tonnes),Fbar,Total stock biomass (tonnes) , spawning stock biomass (tonnes) , Ln recruitment 1986-1991 Year, Yield, Fbar, 1SB, SSB, log R 2-10 1986, 405.8, .2286, 2597.0, 2597.0, 10.13 1987, 438.2, .2439, 2539.7, 2539.7, 10.10 1988, 536.6, .3602, 2441.7, 2441.7, 10.14 1989, 506.1, .3919, 2322.8, 2322.8, 10.30 1990, 586.8, .4907, 2397.6, 2397.6, 10.54 1991, 643.5, .5289, 2158.0, 2158.0, 10.03 126 Table 5.9.14 VPA. Botney Gut- Silver Pit (Functional Unit 5) : Females Catch (OOO's) at 'nominal age' . 1986-1991 Age 1986 1987 1988 1989 1990 1991 1 155. 276. 216. 405. 153. 538. 2 603. 944. 925. 855. 714. 1766. 3 1247. 1460. 1825. 954. 702. 1899. 4 1169. 1160. 802. 963. 426. 1347. 5 532. 791. 655. 999. 622. 736. 6 328. 569. 566. 1054. 928. 847. 7 281. 339. 536. 1177. 952. 981. 8 216. 255. 276. 626. 825. 522. 9 156. 191- 174. 439. 784. 622. 10 76. 95. 101. 338. 373. 496. 11 51- 62. 98. 126. 263. 256. 12 32. 30. 66. 96. 201. 262. 13 19. 18. 35. 83. 148. 197• 14 13. 11- 29. 81. 108. 121. 15 8. 6. 28. 54. 67. 83. • 16 48. 27. 57. 134. 139. 186. Table 5.9.15 VPA. Botney Gut- Silver Pit (Functional Unit 5) : Females Mean weight (kg) at 'nominal age' .1986-1991 Age 1986 1987 1988 1989 1990 1991 1 .0140 .0140 .0140 .0140 .0140 .0140 2 .0180 .0180 .0180 .0180 .0180 .0180 3 .0220 .0220 .0220 .0220 .0220 .0220 4 .0260 .0260 .0260 .0270 .0270 .0260 • 5 .0310 .0310 •0320 .0320 .0320 . .0320 6 .0360 .0360 .0360 .0360 .0360 .0360 7 .0410 .0410 .0410 .0410 .0410 .0410 8 .0460 .0460 .0460 .0460 .0460 .0460 9 .0510 .0500 .0510 .0500 .0510 .0510 10 .0560 .0560 .0560 .0560 .0560 .0560 11 .0600 .0600 .0600 .0600 .0600 .0610 12 .0640 .0640 .0650 .0650 .0650 .0650 13 .0690 .0690 .0690 .0690 .0690 .0690 14 .0730 .0730 .0740 .0740 .0730 .0730 15 .0770 .0770 .0770 .0760 .0710 .0770 16 .0970 .0930 .0910 .0930 .0920 .0900 127 Table 5.9.16 VPA. Botney Gut- Silver Pit (Functional Unit 5): Females Fishing mortality (F) at 'nominal age'. 1986-1991 Age 1986 1987 1988 1989 1990 1991 1 .0031 .0071 .0042 .0079 .0022 .2000 2 .0119 .0231 .0295 .0205 .0172 .0316 3 .0364 .0359 .0566 .0384 .0210 .0581 4 .0353 .0430 .0248 .0383 .0216 .0510 5 .0185 .0302 .0308 .0389 .0313 .0471 6 .0217 .0248 .0271 .0633 .0461 .0543 7 .0199 .0280 .0293 .0724 .0748 .0628 8 .0211 .0226 .0287 .0433 .0664 .0534 9 .0588 .0233 .0192 .0581 .0700 .0653 10 .0268 .0462 .0153 .0471 .0641 .0576 11 .0290 .0273 .0610 .0239 .0468 .0570 12 .0231 .0219 .03n .0782 .0482 .0601 13 .0149 .0162 .0314 .0594 .1667 .0608 14 .0274 .0105 .0325 .0952 .1030 .2000 15 .0218 .0162 .0337 .0776 .1060 .1070 16 .0218 .0162 .0337 .0776 .1060 .1070 Table 5.9.17 VPA. Botney Gut- Silver Pit (Functional Unit 5): Females 'nominal age' .1986-1991 • Population numbers (OOO's) at Age 1986 1987 1988 1989 1990 1991 1 55929. 43233. 56955. 56763. 76623. 3262. 2 56484. 45651. 35147. 46435. 46108. 62596. 3 38526. 45699. 36522. 27938. 37244. 37104. 4 37147. 30413. 36094. 28255. 22010. 29858. 5 31932. 29355. 23853. 28826. 22261. 17635. 6 16893. 25662. 23318. 18937. 22697. 17663. 7 15707. 13534. 20495. 18579. 14553. 17746. 8 11407. 12606. 10774. 16295. 14150. 11056. 9 3014. 9144. 10090. 8571. 12776. 10840. 10 3157. 2327. 7314. 8104. 6622. 9753. 11 1948. 2516. 1819. 5897. 6330. 5084. 12 1564. 1549. 2004. 1401- 4714. 4945. 13 1421. 1251. 1241. 1581. 1061. 3678. 14 543. 1147. 1008. 984. 1220. 735. 15 425. 432. 929. 799. 733. 901. 16 2466. 1826. 1891. 1974. 1518. 2016. • Females Table 5.9.18 VPA. Botney Gut- Silver Pit (Functional Unit 5): Yield (tonnes),Fbar,Total stock biomass (tannes) , spawning stock biomass (tannes) , Ln recruitment 1986-1991 Year, Yield, Fbar, TSB, SSB, Log R 2-13 1986, 145.5, .0264, 7337.0, 7337.0, 10.93 1987, 179.3, .0285, 7402.5, 7402.5, 10.67 1988, 193.2, .0326, 7678.0, 7678.0, 10.95 1989, 297.9, .0485, 7877.0, 7877.0, 10.95 1990, 297.9, .0562, 8160.3, 8160.3, 11.25 1991, 372.0, .0549, 7490.2, 7490.2, 8.09 128 Table 5.9.19 Nephrops landings (tonnes by Functional Unit plus other rectangles in Management Area (H) - (IVb & IVc East of 1° East) Year FU5 Other rectangles Total 1982 ==457 ? ==457 1983 ~636 ? ~636 1984 ~613 ? ~613 1985 ~680 ==1 ~681 1986 ==382 ==10 ==392 1987 ==433 ==4 ==437 1988 546 73 619 1989 645 131 776 1990 747 123 870 1991 759 167 926 Table 5.9.20 Total Nephrops landings (t) by country in Management Area (H) - (IVb & IVc East of 1° East) Year Belgium Denmark UK TOTAL 1982 ==457 ? 0 ==457 1983 ==633 ? 3 ==636 1984 ==612 ? 1 ==613 1985 ==680 ? 1 ==681 1986 ==380 ? 4 ==392 1987 ~431 ? 6 ==437 1988 492 122 5 619 1989 563 210 3 776 1990 600 266 4 870 1991 606 315 5 926 • 129 Table 5.10.1 Farn Deeps (Functional Unit 6) landings (in tonnes), by country, 1982-91 Year UK Denmark Belgium Total 1982 2 523 + ? :2: 2 523 83 2 078 + ? :2: 2 078 84 1 483 + ? :2: 1 483 85 2 028 + ? :2: 2 028 86 2 015 + 0 :2: 2 015 1987 2 193 + 0 :2: 2 193 88 2 494 10 0 2 504 89 3 098 1 0 3 099 90 2 498 + 0 2 498 91 (* ) 2 059 1 1 2 061 (*) provisional Table 5.10.2 Farn Deeps (Functional Unit 6) : catches and landings (in tonnes), effort (in '000 hours trawling), CPUE and LPUE (in kg/hour trawling) of UK Nephrops trawlers, 1982-91 Season Catches Landings Effort CPUE LPUE 1981/82 ? 1 394 53 ? 26 82/83 ? 2 278 76 ? 30 83/84 ? 1 922 75 ? 26 84/85 3 068 1 600 63 49 25 85/86 4 127 2 175 96 43 23 1986/87 3 040 2 140 94 33 23 87/88 4 767 2 131 110 44 19 88/89 4 895 2 614 118 43 22 89/90 4 295 2 814 133 34 21 90/91 (* ) NA 2 972 127 NA 23 (*) provisional Figures are for years ending June 30th Table 5.10.3 Farn Deeps (Functional Unit 6) : mean sizes (CL in mm) of male and female Nephrops in Eng- lish catches and landings, 1982-91 • Catch Landings Season Males Females Males Females 1981/82 ? ? 37.2 35.8 82/83 ? ? 36.9 34.7 83/84 ? ? 36.5 33.9 84/85 29.6 27.1 35.6 33.9 85/86 30.1 28.7 35.2 33.7 1986/87 30.5 29.6 34.7 33.2 87/88 28.1 26.1 35.0 32.4 88/89 28.1 26.8 32.7 32.1 89/90 28.7 28.0 32.2 31.3 90/91 24.8(*) 24.4(*) 32.2 31. 9 91/92 26.3(·) 24.2(·) NA NA (*) Sampies only available for November in 1990 and 1991 130 Iahle 5.10.4 VPA. Farn Deeps (Functional Unit 6): Males Catch (OOO's).at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 3980. 2319. 3508. 12053. 7184. 10649. 10766. 2 28374. 34546. 19645. 61340. 72646. 45628. 64113. 3 24563. 46704. 21294. 38988. 46338. 45534. 44123. 4 16057. 19509. 11864. 17695. 15838. 18512. 15126. 5 5218. 6779. 5887. 7608. 5910. 5559. 5316. 6 2626. 2581. 2390. 2962. 2518. 2247. 2324. 7 906. 1186. 1126. 1212. 1129. 793. 810. 8 441. 601. 553. 592. 467. 342. 330. 9 194. 321. 314. 276. 232. 146. 145. 10 85. 172. 167. 146. 102. 65. 59. 11 154. 295. 284. 205. 166. 85. 76 • • Males Iahle 5.10.5 VPA. Farn Deeps (Functional Unit 6): Mean weight (kg) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0050 .0060 .0050 .0050 .0050 .0040 .0050 • 2 .0100 .0120 .0110 .0110 .0110 .0110 .0110 3 .0210 .0200 .0200 .0200 .0200 .0200 .0200 4 .0330 .0320 .0330 .0330 .0320 .0320 .0320 5 .0470 .0470 .0470 .0470 .0470 .0460 .0470 6 .0620 .0610 .0620 .0620 .0620 .0620 .0610 7 .0790 .0790 .0780 .0790 .0780 .0780 .0780 8 .0920 .0920 .0930 .0920 .0920 .0920 .0930 9 .1070 .1080 .1070 .1070 .1070 .1070 .1060 10 .1210 .1210 .1210 .1210 .1200 .1210 .1200 11 .1520 .1510 .1490 .1480 .1480 .1460 .1450 131 Table 5.10.6 VPA. Farn Deeps (Functional Unit 6): Males Fishing mortality (F) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0233 .0131 .0142 .0479 .0328 .0385 .1000 2 .2042 .3197 .1633 .4080 .5019 .3332 .3803 3 .3493 .6882 .3754 .6346 .7131 .7934 .7160 4 .5843 .5898 .4182 .7072 .6648 .8201 .7834 5 .4565 .6018 .3988 .5935 .6247 .5943 .6817 6 .4820 .4878 .5005 .4047 .4513 .5901 .6124 7 .3423 .4743 .4627 .5862 .2974 .2791 .49n 8 .3094 .4538 .4809 .5391 .5365 .1533 .2000 9 .2670 .4382 .5182 .5363 .4770 .3566 .1000 10 .3062 .4554 .4873 .5539 .4370 .2630 .2659 11 .3062 .4554 .4873 .5539 .4370 .2630 .2659 Table 5.10.1 VPA. Farn Deeps (Functional Unit 6): Males Population numbers (OOO's) at 'nominal age'. 1984-1990 Age • 1984 1985 1986 1987 1988 1989 1990 1 200325. 205559. 287293. 298014. 257840. 325983. 130621. 2 176876. 144979. 150286. 209812. 210451. 184857. 232372. 3 95615. 106826. 78012. 94557. 103358. 94371. 98139. 4 41400. 49951. 39764. 39702. 37137. 37527. 31621- 5 16295. 17098. 20517• 19388. 14500. 14152. 12243. 6 7853. 7647. 6940. 10201. 7934. 5751. 5787. 7 3587. 3592. 3478. 3116. 5042. 3743. 2362. 8 1904. 1887. 1656. 1622. 1285. 2n4. 2097. 9 950. 1035. 888. 758. 701- 556. 1763. 10 368. 539. 495. 392. 329. 322. 289. 11 671. 924. 842. 549. 536. 420. 376. Table 5.10.8 VPA. Farn Deeps (Functional Unit 6): Males Yield (tonnes),Fbar,Total stock biomass (tannes), spawning stock biomass (tannes), Ln recruitment 1984-1990 • Year, Yield, Fbar, 1SB, SSB, log R 3- 7 1984, 1923.9, .4429, 8104.1, 8104.1, 12.21 1985, 2712.0, .5684, 8752.1, 8752.1, 12.23 1986, 1711.3, .4311, 8062.3, 8062.3, 12.57 1987, 2867.5, .5852, 9148.2, 9148.2, 12.60 1988, 2895.1, .5503, 8738.3, 8738.3, 12.46 1989, 2571.7, .6154, 8140.2, 8140.2, 12.69 1990, 2644.6, .6582, 7767.6, 7767.6, 11-78 132 Table 5.10.9 VPA. Farn Deeps (Functional Unit 6) : Females Catch (OOO's) at 'nominal age' . 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 1050. 725. 627. 6852. 4410. 6351. 6477. 2 30937. 20252. 14967. 51396. 57008. 35365. 62364. 3 8499. 8232. 7904. 16958. 13935. 13399. 16521. 4 4486. 7340. 8025. 14059. 8456. 13130. 12498. 5 4519. 7238. 6990. 8638. 6498. 11015. 10767. 6 5430. 5676. 5847. 5266. 6523. 8683. 10179. 7 3470. 4050. 4586. 3426. 5312. 6658. 7197. 8 2171. 2914. 3685. 2272. 4325. 5178. 5191. 9 1805. 1997. 2888. 1656. 3122. 3668. 4214. 10 974. 1400. 2103. 1113. 2227. 2599. 2933. 11 378. 971. 1539. 724. 1584. 1832. 2013. 12 349. 597. 917. 462. 850. 946. 1208. 13 342. 519. 786. 407. 695. 760. 1039. 14 187. 324. 461. 202. 424. 386. 504. 15 711. 980. 1490. 622. 1497. 978. 1188. Table 5.10.10 VPA. Farn Deeps (Functional Unit 6): Females Mean weight (kg) at 'nominal age' .1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0040 .0030 .0040 .0040 .0040 .0030 .0040 2 .0080 .0080 .0080 .0080 .0080 .0080 .0080 3 .0110 .0120 .0120 .0120 .0110 .0120 .0110 4 .0140 .0140 .0140 .0140 .0140 .0140 .0140 5 .0160 .0160 .0160 .0160 .0160 .0160 .0160 6 .0190 .0190 .0190 .0190 .0190 .0190 .0190 7 .0210 .0210 .0210 .0210 .0210 .0210 .0210 • 8 .0240 .0240 .0240 .0240 .0240 .0240 .0240 9 .0270 .0270 .0270 .0270 .0270 .0270 .0270 10 .0280 .0290 .0290 .0290 .0290 .0290 .0290 11 .0320 .0320 .0320 .0320 .0320 .0320 .0320 12 .0360 .0350 .0350 .0350 .0350 .0350 .0350 13 .0370 .0370 .0370 .0370 .0370 .0370 .0370 14 .0410 .0410 .0410 .0400 .0410 .0400 .0400 15 .0500 .0480 .0490 .0490 .0480 .0480 .0480 133 Table 5.10.11 VPA. Farn Deeps (Functional Unit 6): Females Fishing mortality (F) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0036 .0025 .0020 .0239 .0177 .0202 .1000 2 .1500 .0980 .0720 .2547 .3140 .2134 .3135 3 .0585 .0572 .0532 .1152 .1072 .1190 .1548 4 .0413 .0656 .0726 .1261 .0773 .1394 .1554 5 .0433 .0868 .0821 .1042 .0790 .1367 .1623 6 .0796 .0703 .0937 .0820 .1068 .1438 .1806 7 .0643 .0785 .0746 .0729 .1113 .1513 .1702 8 .0736 .0706 .0951 .0480 .1239 .1508 .1690 9 .0969 .0897 .0926 .0564 .0861 .1468 .1765 10 .0723 .1014 .1285 .0468 .1000 .0959 .1677 11 .0478 .0957 .1545 .0595 .0869 .1116 .1000 12 .0619 .0993 .1230 .0633 .0919 .0686 .1000 13 .0835 .1233 .1834 .0737 .1278 .1110 .1000 14 .0644 .1061 .1536 .0655 .1022 .0971 .1000 15 .0644 .1061 .1536 .0655 .1022 .0971 .1000 Table 5.10.12 VPA. Farn Deeps (Functional Unit 6): Females Population numbers (OOO's) at 'nominal age'. 1984-1990 • Age 1984 1985 1986 1987 1988 1989 1990 1 339478. 336852. 355634. 335864. 291143. 366616. 78587. 2 256125. 250588. 248922. 262920. 242942. 211888. 266130. 3 164969. 163313. 168316. 171595. 150981. 131469. 126805. 4 122146. 127396. 126280. 130672. 125201. 111047. 95558. 5 117505. 95945. 97680. 96149. 94311. 94877. 79084. 6 78199. 92126. 72024. 73668. 70931. 71353. 67751. 7 61384. 59126. 70305. 53695. 55564. 52191. 50594. 8 33717. 47127. 44754. 53423. 40871. 40703. 36731. 9 21521. 25647. 35955. 33318. 41688. 29564. 28659. 10 15393. 15992. 19196. 26833. 25784. 31315. 20900. 11 8919. 11724. 11831. 13821. 20964. 19101. 23294. 12 6395. 6961. 8723. 8300. 10663. 15735. 13987. 13 4706. 4921. 5161. 6315. 6378. 7964. 12029. 14 . 3308. 3544. 3562. 3518. 4803. 4596. 5835. 15 12552. 10725. 11512. 10822. 16969. 11645. 13753. • Table 5.10.13 VPA. Farn Deeps (Functional Unit p): Females Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1990 Year, Yield, Fbar, TSB, SSB, Log R 3-10 1984, 864.9, .0662, 14860.8, 11453.9, 12.74 1985, 970.4, .om, 15034.0, 12018.7, 12.73 1986, 1078.4, .0865, 15795.9, 12382.0, 12.78 1987, 1373.6, .0815, 15998.4, 12551.5, 12.72 1988, 1532.9, .0989, 15690.9, 12582.8, 12.58 1989, 1608.6, .1355, 14779.6, 11984.7, 12.81 1990, 1944.1, .1671, 13626.1, 11182.8, 11.27 134 Table 5.10.14 Firth of Forth (Functional Unit 8) : landings (in tonnes), by gear,1982-91, all UK Year Nephrops Trawl Other Trawl Total 1982 1 138 58 1 196 83 1 681 41 1 722 84 2 078 56 2 134 85 1 908 61 1 969 86 2 204 59 2 263 1987 1 582 92 1 674 88 2 455 73 2 528 89 1 833 52 1 885 90 1 901 30 1 931 91(-) 1 359 43 1 402 (·)provisional Table 5.10.15 Firth of Forth (Functional Unit 8) : landings (in tonnes), effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Scottish Nephrops trawlers, 1982-91. Single and multi-rig trawls combined (see Table 6.4 ) Year Landings Effort LPUE 1982 1 138 51. 7 22.0 83 1 681 60.7 27.7 84 2 078 84.7 24.5 85 1 908 73.9 25.8 86 2 204 74.7 29.5 1987 1 582 62.1 25.5 88 2 455 94.8 25.9 89 1 833 78.7 23.3 90 1 901 81.8 23.1 91 (- ) 1 359 69.4 19.6 (-)provisional Table 5.10.16 Firth of Forth (Functional unit 8) : mean sizes of male and female Nephrops (CL in mm) • in Scottish landings, 1982-91 Year Males Females 1982 34.4 33.4 83 34.5 32.9 84 34.2 31.4 85 33.3 31.0 86 31. 8 30.4 1987 32.3 31.2 88 30.1 29.4 89 30.4 30.4 90 31.4 30.3 91 31.2 30.1 135 Iable 5.10.17 VPA. Firth of Forth (Functional Unit 8): Males Catch (000'5) at 'nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 '1988 1989 1990 1991 1 146. 6387. 632. 17245. 7255. 6515. 3787. 36873. 9484. 2834. 1720. 2 2848. 6944. n05. 14441. 12858. 28624. 20425. 46156. 25870. 30846. 24503. 3 10103. 10351. 19501. 20878. 24517. 27876. 21673. 25097. 21318. 28250. 23194. 4 6301. 6553. 10656. 15247. 10988. 9496. 8513. 11950. 7422. 8659. 7064. 5 2667. 2787. 4046. 6396. 3863. 3512. 2930. 4256. 2319. 2067. 1671. 6 992. 1384. 1636. 2317. 1316. 1083. 919. 1433. 652. 589. 405. 7 315. 427. 597. 636. 358. 306. 341- 483. 249. 179. 107. 8 122. 187. 253. 202. 104. 102. 107. 136. 88. 42. 33. 9 51. 79. 91. 59. 38. 37. 31. 50. 42. 11. 8. 10 22. 23. 36. 27. 18. 19. 12. 19. 12. 4. 1. 11 31. 34. 35. 49. 13. 20. 14. 16. 11. 6. 1- • Iable 5.10.18 VPA. Firth of Forth (Functional Unit 8): Males Mean weight (kg) at 'nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0050 .0050 .0060 .0050 .0050 .0050 .0060 .0050 .0050 .0060 .0060 .0120 2 .0130 •0120 .0120 .0110 .0120 .0120 .0110 .0110 .0120 .012• 3 .0220 .0220 .0220 .0210 .0210 .0210 .0210 .0210 .0210 .0210 .0210 4 .0340 .0330 .0330 .0340 .0330 .0330 .0330 .0340 .0330 .0330 .0330 5 .0480 .0490 .0480 .0480 .0480 .0480 .0480 .0480 .0480 .0470 .0480 6 .0640 .0640 .0640 .0630 .0630 .0630 .0630 .0640 .0640 .0640 .0630 7 .0790 .0790 .0800 .0790 .0790 .0790 .0790 .0790 .0790 .0790 .0790 8 .0950 .0950 .0940 .0930 .0940 .0940 .0940 .0940 .0950 .0930 .0940 9 .1070 .1070 .1070 .1070 .1090 .1090 .1070 .1080 .1070 .1060 .1050 10 .1230 .1190 .1220 .1230 .1210 .1220 .1230 .1210 .1180 .1240 .1230 11 .1480 .1660 .1460 .1610 .1390 .1460 .1510 .1460 .1460 .1480 .1420 136 Table 5.10.19 VPA. Firth of Forth (Functional Unit 8): Males Fishing mortality (F) at 'nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0014 .0660 .0061 .1508 .0603 .0635 .0291 .2832 .0782 .0243 .2000 2 .0503 .0961 .1177 .2063 .1787 .3976 .3227 .6496 .3702 .4372 .3349 3 .3547 .2901 .4765 .6003 .7304 .8292 .6843 .9726 .8387 1.0490 .8021 4 .5351 .4649 .6234 1.0104 .8691 .8237 .7620 1.2771 1.0649 1.2491 .9862 5 .5412 .5487 .6748 1.1m .9133 .9085 .7625 1.4243 1.1382 1.2433 1.0524 6 .5695 .6953 .8561 1.3234 .9853 .8340 .7443 1.3644 1.0729 1.2913 1.0650 7 .4749 .5901 .8732 1.2186 .8682 .7549 .8085 1.4714 1.1601 1.2363 1.0548 8 .4562 .6646 1.0121 1.0087 .7563 .7662 .7568 1.0995 1.7087 .7085 .9570 9 .5811 .6992 .9494 .8074 .5833 .7937 .6255 1.2466 1.7402 1.3860 .3000 10 .5041 .6513 .9449 1.0116 .7359 .7716 .7302 1.2725 1.5363 1.1103 .7706 11 .5041 .6513 .9449 1.0116 .7359 .7716 .7302 1.2725 1.5363 1.1103 .7706 4ItTable 5.10.20 VPA. Firth of Forth (Functional Unit 8): Males Population numbers (OOO's) at •nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 118242. 115507. 121176. 142102. 143367. 122305. 152935. 171828. 145592. 136674. 10931. 2 67058. 87470. 80102. 89226. 90539. 99997. 85028. 110052. 95895. 99740. 98822. 3 38815. 47239. 58860. 52753. 53780. 56096. 49773. 45615. 42580. 49059. 47721. 4 17371. 20167. 26183. 27076. 21441. 19193. 18135. 18599. 12777. 13636. 12730. 5 7287. 7535. 9385. 10399. 7302. 6661. 6239. 6270. 3842. 3263. 2897. 6 2608. 3142. 3225. 3540. 2374. 2170. 1989. 2156. 1118. 912. 697. 7 952. 1093. 1161. 1015. 698. 656. 698. 700. 408. 283. 186. 8 381. 439. 449. 359. 222. 217. 229. 230. 119. 95. 61. 9 132. 179. 167. 121. 97. 77. 75. 79. 57. 16. 35. 10 64. 54. 66. 48. 40. 40. 26. 30. 17. 7. 3. 11 88. 80. 64. 86. 29. 42. 31. 25. 16. 10. 3. Table 5.10.21 VPA. Firth of Forth (Functional Unit 8): Males Yield (tonnes),Fbar.Total stock biomass (tonnes) • • spawning stock biomass (tonnes). Ln recruitment 1981-1991 Year, Yi eld, Fbar, 1SB, SSB, log R 3- 8 1981, 714.9, .4886, 3570.6, 3570.6, 11.68 1982, 852.6, .5423, 4069.2, 4069.2, 11.66 1983, 1266.5, .7527, 4674.4, 4674.4, 11.71 1984, 1741.4, 1.0565, 4588.9, 4588.9, 11.86 1985, 1382.5, .8538, 4235.8, 4235.8, 11.87 1986, 1554.7, .8194, 4171.1, 4171.1, 11.71 1987, 1246.3, .7531, 4099.0, 4099.0, 11.94 1988, 1982.4, 1.2682, 4191.7, 4191.7, 12.05 1989, 1213.2, 1.1639, 3408.5, 3408.5, 11.89 1990, 1421.6, 1.1296, 3744.1, 3744.1, 11.83 1991, 1143.1, .9862. 2881.5. 2881.5. 9.30 137 Table 5.10.22 VPA. Firth of Forth (Functional Unit 8): Females Catch (OOO's) at 'nominal age' . 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 413. 2152. 1144. 5292. 1213. 3367. 550. 29517. 6245. 2821. 2809. 2 222. 792. 646. 2121. 1891. 5376. 2455. 11129. 5114. 6299. 5867. 3 685. 1089. 1681. 3862. 3129. 12464. 5727. 11789. 8118. 11372. 8758. 4 1543. 1471. 2895. 4793. 5423. 13832. 6552. 10914. 8461. 9899. 7700. 5 1895. 1212. 3744. 4817. 5020. 11213. 6013. 7384. 6224. 6534. 5382. 6 1984. 1476. 3608. 4039. 3845. 7402. 4743. 5886. 4427. 4610. 3951. 7 1779. 1296. 3206. 2950. 2765. 4978. 3573. 4789. 3693. 3327. 2667. 8 1557. 1075. 2391. 2101. 1826. 3306. 2519. 3658. 3013. 2442. 1791. 9 1375. 900. 1419. 1501. 1043. 2080. 1612. 2568. 2311. 1812. 1227. 10 880. 659. 1105. 804. 552. 1264. 977. 1657. 1749. 1149. 628. 11 711. 587. 881. 608. 416. 944. 686. 1443. 1427. 897. 484. 12 511. 503. 616. 378. 257. 566. 343. 1192. 1047. 600. 315. 13 303. 277. 375. 273. 139. 361. 229. 618. 648. 420. 216. 14 232. 200. 293. 237. 99. 291. 190. 423. 513. 359. 183. e 15 139. 107. 152. 129. 67. 168. 93. 278. 281. 204. 118. 16 420. 379. 382. 333. 168. 501. 253. 972. 737. 632. 403. Table 5.10.23 VPA. Firth of Forth (Functional Unit 8): Females Mean weight (kg) at 'nominal age' .1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0040 .0040 .0040 .0040 .0040 .0050 .0040 .0040 .0040 .0050 .0050 2 .0070 .0070 .0070 .0060 .0070 •0070 .0070 .0060 .0070 .0070 .0070 3 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 4 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0100 • 5 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 6 .0150 .0150 .0150 .0150 .0150 .0150 .0150 .0150 .0150 .0150 .0150 7 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 8 .0190 .0190 .0190 .•0190 .0190 .0190 .0190 .0190 .0190 .0190 .0190 9 .0210 .0210 .0210 .0210 .0210 .0210 .0210 .0210 .0210 .0210 .0210 10 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 .0250 11 .0260 .0260 .0260 .0260 .0260 .0260 .0250 .0260 .0260 .0260 .0260 12 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 .0280 13 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 14 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 .0330 15 .0360 .0360 .0360 .0360 .0360 .0360 .0360. .0360 .0360 .0360 .0360 16 .0440 .0450 .0430 .0430 .0420 .0430 .0430 .0440 .0420 .0440 .0440 138 Table 5.10.24 VPA. Firth of Forth (Functional Unit 8): Females Fishing mortality (F) at 'nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 . 1991 1 .0038 .0184 .0097 .0468 .0111 .0299 .0047 .2213 .0425 .0159 .2000 2 .0028 .0093 .0072 .0236 .0223 .0658 .0289 .1314 .0571 .0580 .0439 3 .0113 .0168 .0246 .0543 .0440 .1995 .0927 .1882 .1337 .1735 .1068 4 .0329 .0302 .0566 .0907 .1005 .2768 .1530 .2554 .2003 .2391 .1704 5 .0559 .0327 .1000 .1257 .1293 .3095 .1858 .2578 .2267 .2345 .1978 6 .0867 .0563 .1284 .1490 .1400 .2850 .2079 .2795 .2426 .2614 .2172 7 .1215 .0750 .1664 .1471 .1442 .2706 .2165 .3346 .2838 .2900 .2372 8 .1481 .1003 .1925 .1565 .12n .2565 .2134 .3589 .3642 .30n .2503 9 .1950 .1196 .1861 .1n8 .1085 .2097 .1915 .3504 .4048 .3896 .2503 10 .1766 .1348 .211 1 .1527 .0915 .1857 .1438 .3073 .4288 .3614 .2259 11 .1990 .1712 .2680 .1720 .1102 .2228 .1454 .3262 .4739 .4086 .2539 12 .2201 .2109 .2730 .1757 .1021 .2149 .11n .4016 .4174 .3737 .2446 13 .2235 .1n7 .2408 .1864 .0904 .2033 .1261 .3203 .3979 .2934 .2229. 14 .•2838 .2257 .2896 .2361 .0951 .2760 .1569 .3602 •4800 .4010 . .2000 15 .2419 .2044 .2674 .1992 .0958 .2313 .1335 .3606 .4317 .3559 .2224 16 .2419 .2044 .2674 .1992 .0958 .2313 .1335 .3606 .4317 .3559 .2224 ~ Table 5.10.25 VPA. Firth of Forth (Functional Unit 8): Females Population numbers (OOO's) at 'nominal age' .. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 127405. 136250. 136684. 133864. 126922. 132168. 134919. 171123. 173589. 206518. 17845. 2 88257. 94029. 99084. 100274. 94636. 92982. 95027. 994n. 101598. 123249. 150564. 3 67410. 72058. 76268. 80538. 80178. 75nO. 71277. 75580. 71414. 78566. 95223. 4 52521. 54571. 58011. 60922. 62454. 62820. 50814. 53191. 51263 •. 51151. 54081. 5 38413. 41604. 43348. 44883. 45555. 46243. 38995. 35699. 33732. 34353. 32973. 6 26330. 29740. 32966. 32114. 32405. 32m. 2n83. 26512. 22586. 22016. 22247. 7 17118. 19768. 23017. 23738. 22653. 23066. 201n. 184n. 16414. 14509. 13879. 8 12446. 12412. 15015. 15956. 16m. 16056. 14408. 13304. 10825. 10118. 8888. 9 8539. 8787. 9192. 10141. 11171. 12089. 10172. 9529. 7608. 6157. 6089. 10 5982. 5753. 6383. 6248. ·6951. 8206. 8026. 6876. 5495. 4155. 3414. 11 4332. 4105. 4116. 4231. 4391. 5193. 5580. 5691. 4140. 2930. 2370. 12 2846. 2907. 2832. 2578. 2917. 3220. 3402. 3951. 3362. 2110. 1594. 13 1661. 1870. 1927. 1765. 1no. 2156. 2127. 2476. 2165. 1813. 1189. 14 1029. 1088. 1281. 1240. 1199. 1~24. 1441. 1535. ·1472. 1190. 1107. 15 708. 635. 711. 785. 802. 893. 823. 1008. 876. 746. 653 • • 16 2148. 2255. 1787. 2024. 2028. 2669. 2226. 3520. 2304. 2315. 2221. Table 5.10.26 VPA. Firth of Forth (Functional Unit 8): Females Yleld (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1981-1991 Year, Yield, Fbar, TSB, SSB, Log R 3-10 1981, 260.6, .1035, 4302.0, 3792.3, 11.76 1982, 217.5, .0707, 45n.2, 4032.2, 11.82 1983, 391.2, .1332, 4865.2, 4318.5, 11.83 1984, 434.4, .1317, 4880.0, 4344.5, 11.80 1985, 367.7, .1107, 4985.4, 44n.7, 11.75 1986, 849.6, .2492, 5231.4, 4570.6, 11.79 1987, 495.2, .1756, 4672.5, 4132.8, 11.81 1988, 968.3, .2915, 4760.0, 4075.5, 12.05 1989, 708.2, .2856, 4460.7, 3766.3, 12.06 1990, 665.6, .2822, 4809.4, 3n6.8, 12.24 1991, 503.0, .2070, 4094.1, 4004.9, 9.79 139 Nephrops landings (tonnes by Functional Unit plus other Table 5.10.27 0 rectangles in Management Area (IVb,c West of 1 East) (Area I) Year FU6 FU8 Other rectangles Total 1982 2523 1196 156 3875 1983 2076 1722 98 3898 1984 1483 2134 77 3694 1985 2028 1969 107 4104 1986 2015 2263 143 4421 1987 2193 1674 138 4005 1988 2504 2528 310 5342 1989 3099 1885 156 5140 1990 2498 1931 131 4560 1991 2061 1402 386 3849 Table 5.10.28 Total Nephrops landings (t) by country in Management 0 Area (IVb,c West of 1 East) (Area I) Year UK Denmark Belgium TOTAL 1982 3875 + ? 3875 1983 3898 + ? 3898 1984 3694 + ? 3694 1985 4104 + ? 4104 1986 4421 + 0 4421 1987 4005 + 0 4005 1988 5330 12 0 5342 1989 5138 2 0 5140 1990 4555 1 4 4556 1991 3845 1 3 3849 • 140 Table 5.11.1 Irish Sea East (Functional Unit 14) : landings (in tannes), by country of landing (all UK). 1982-91 Year England Northern Scotland Total & Wales Ireland 1982 869 5 23 897 83 763 1 1 765 84 602 3 14 619 85 498 10 11 519 86 664 7 15 686 1987 445 22 4 471 88 462 32 3 497 89 394 36 1 431 90 549 70 11 630 91 (.) 725 87 25 837 (.) provisional Table 5.11.2 Irish Sea East (Functional Unit 14) : effort (in '000 hours trawling) and LPUE (in kg/hour trawling) of Nephrops directed voyages by UK trawlers, 1982-91 Year Effort LPUE 1982 26.8 29 83 24.1 28 84 21.9 24 85 14.7 29 86 19.6 29 1987 22.4 15 88 18.9 19 89 18.2 17 90 17.6 25 91 (.) 19.7 27 (.) provisional • Table 5.11.3 Irish Sea East (Functional Unit 14) : mean sizes (CL in mm) of male and female Nephrops from UK vessels landing in England and Wales, 1985-91 Year Males Females 1985 32.0 29.3 86 32.2 29.5 87 35.9 32.5 88 37.9 36.4 89 (.) ? ? 90 (.) ? ? 91 32.1 33.4 (.) Inadequate sampling to allow estimation of mean size 141 Table 5.11.4- Irish Sea West (Functional Unit 15) landings (in tonnes), by country, 1982-91 Year UK Rep. of Isle of France Total Ireland Man 1982 4 549 4 235 363 87 9 234 83 4 954 3 747 170 27 8 898 84 4 156 2 704 169 41 7 070 85 4 394 1 991 3 42 6 430 86 5 243 3 404 7 93 8 747 1987 5 043 4 141 18 55 9 257 88 5 283 2 870 39 62 8 254 89 5 580 2 458 8 19 8 065 90 5 535 2 709 2 8 277 91{*) 6 024 3 366 57 12 9 459 (*) provisional Table 5.11.5 Irish Sea West (Functional Unit 15) : catches and landings (in tonnes), effort (in '000 hours trawling), CPUE and LPUE (Kg/hour) of Northern Ireland Nephrops trawlers. 1982-91 Year Catches Landings Effort CPUE LPUE 1982 6 727 4 482 140.82 47.8 31.8 83 6 410 4 949 NA NA NA 84 5 191 4 027 141. 86 36.6 28.4 85 5 409 4 310 154.47 35.0 27.9 86 6 282 5 197 152.41 41.2 34.1 1987 5 739 4 990 171. 04 33.6 29.2 88 5 669 5 220 168.20 33.7 31.0 89 6 232 5 517 196.95 31.6 28.0 90 5 691 5 505 195.77 29.1 28.1 91 6 145 5 926 NA NA NA (*) provisional • 142 Table 5.11.6 Irish Sea West (Functional Unit 15) : mean sizes (CL in mm) of male and female Nephrops in Northern Ireland catches, 1982-91 Year Males Females 1982 24.4 22.1 83 24.5 22.2 84 26.2 23.2 85 25.9 23.0 86 26.5 23.6 1987 26.8 23.9 88 27.5 24.5 89 26.4 23.8 90 26.3 24.0 91 26.6 25.2 e Table 5.11. 7 Irish Sea West (Functional Unit 15) : mean weight (in grams) of Nephrops in Republic of Ireland catchest landings and discards. 1971 and 1984-91 Year Catch Landings Discards 1971 12.6 16.6 8.4 1984 10.9 16.2 7.6 1985 10.5 14.9 7.7 1986 11. 0 14.4 7.5 1987 11.4 14.9 7.2 1988 12.3 14.8 8.0 1989 11.5 13.3 8.1 1990 11.2 12.5 7.2 • 1991 10.8 12.3 7.3 143 Table 5.11.8 VPA. Irish Sea west (Functional Unit 15) : Males Catch (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 13974. 18482. 11898. 16620. 5116. 10902. 11382. 6467. 2 145189. 184962. 192065. 159315. 105482. 163581. 137021. 164669. 3 157726. 156317. 203392. 217761. 155938. 184169. 165331. 194391. 4 70018. 56949. 65908. 89598. 70170. 48593. 58092. 62597. 5 22210. 17969. 21711. 30928 •. 19944. 14459. 17914. 20675. 6 8461. 4963. 6066. 8232. 4604. 5024. 6033. 7021. 7 2349. 1449. 1875. 3194. 1985. 3025. 2067. 2563. 8 1347. 595. 726. 1409. 846. 618. 574. 962. 9 545. 121. 242. 492. 153. 140. 252. 199. 10 281- 133. 146. 528. 187. 258. 253. 147. 11 143. o. 68. 1538. 145. 240. 109. 134. Table 5.11. 9 VPA. Irish Sea west (Functional Unit 15) : Males Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0030 .0030 .0030 .0030 .0030 .0030 .0030 .0030 2 .0060 .0070 .0070 .0070 .0070 .0070 .0070 •0070 3 .0120 .0120 .0120 .0120 .0120 .0120 .0120 .0120 4 .0210 .0210 .0210 .0210 .0210 .0200 .0210 .0210 • 5 .0310 .0310 .0310 .0310 .0300 .0310 .0310 .0310 6 .0420 .0420 .0420 .0420 .0420 .0430 .0420 .0420 7 .0540 .0530 .0530 .0530 .0530 .0520 .0530 .0530 8 .0650 .0640 .0650 .0650 .0650 .0640 .0640 .0640 9 .0760 .0740 .0740 .0750 .0760 .0780 .0770 .0760 10 .0830 .0850 .0870 .0870 .0870 .0860 .0840 .0860 11 .0960 .0000 .0930 .0970 .0950 .0940 .0940 .0950 144 Table 5.11.10 VPA. Irish Sea west (Functional Uni t 15) : Males Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0146 .0199 .0162 .0225 .0065 .0156 .0133 .2000 2 .2847 .3033 .3282 .3454 .2160 .3269 .3078 .3000 3 .7163 .6432 .7349 .8832 .7754 .8209 .7388 1.1296 4 .8609 .7139 .7190 1.0242 .9572 .6810 .7816 .8159 5 .8285 .6451 .7668 1.0814 .7755 .5980 .6652 .8403 6 .8425 .4980 .5345 .8877 .5059 .5124 .6176 .6923 7 .4596 .3699 .4004 .6940 .6313 .8651 .4654 .6720 8 .7545 .2239 .3608 .6854 .4470 .4643 .4403 .4657 9 .5085 .1492 .1487 .5040 .1580 .1358 .3948 .3000 10 .5742 .2477 .3033 .6278 .4121 .4884 .4335 .4792 11 .5742 .2477 .3033 .6278 .4121 .4884 .4335 .4792 Table 5.11.11 VPA. Irish Sea west (Functional Unit 15) : Males - Population numbers (000' s) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 1112542. 1085400. 858751. 863086. 915079. 814514. 998530. 41088. 2 673615. 812164. 788176. 625938. 625085. 673504. 594023. 729933. 3 350713. 375399. 444243. 420526. 328251. 373107. 359799. 323456. 4 137477. 126931. 146173. 157823. 128801. 111983. 121630. 127330. 5 44719. 43060. 46051. 52764. 41982. 36638. 41985. 41240. 6 16849. 14467. 16735. 15846. 13256. 14322. 14926. 15992. 7 7297. 5375. 6513. 7263. 4832. 5921. 6355. 5963. 8 2890. 3414. 2751. 3233. 2688. 1904. 1847. 2956. 9 1563. 1007. 2022. 1421. 1207. 1274. 887. 881. 10 733. 696. 642. 1291. 636. 763. 824. 443. 11 374. O. 298. 3759. 492. 711. 355 • 402. • Table 5.11.12 VPA. Irish Sea west (Functional Unit 15): Males Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tannes), Ln recruitment 1984-1991 Year, Yield, Fbar, TSB, SSB, log R 3- 8 1984, 5613.4, .7437, 17366.3, 17366.3, 13.92 1985, 5322.5, .5157, 18691.2, 18691.2, 13.90 1986, 6316.7, .5861, 19381.6, 19381.6, 13.66 1987, 7486.8, .8760, 18811.2, 18811.2, 13.67 1988, 5092.2, .6820, 16205.5, 16205.5, 13.73 1989, 5277.0, .6570, 16288.2, 16288.2, 13.61 1990, 5203.5, .6181, 16579.8, 16579.8, 13.81 1991, 5994.0, .7693, 14386.7, 14386.7, 10.62 145 Table 5.11.13 VPA. Irish Sea west (Functional Unit 15): Females Catch (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 17081. 21374. 18124. 19517. 11060. 11156. 8017. 11917• 2 178015. 208261. 247120. 194453. 137122. 165819. 170033. 190047. 3 118304. 105216. 124003. 131273. 108402. 101772. 112355. 109995. 4 48004. 43750. 49491. 41486. 50787. 43998. 43227. 37085. 5 16734. 14234. 19483. 15640. 21639. 15782. 14290. 1076,. 6 6943. 4069. 7209. 7865. 9190. 7702. 5457. 5261. 7 2746. 1972. 3048. 2984. 3868. 4396. 3322. 3921. 8 1534. 676. 1429. 1602. 1572. 2995. 2007. 1489. 9 906. 626. 389. 503. 997. 1673. 1240. 1023. 10 359. 306. 482. 416. 399. 1364. 1237. 777. 11 178. 35. 332. 50. 214. 812. 556. 694. 12 644. 178. 690. 123. 733. 2073. 1240. 1714. - Table 5.11.14 VPA. Irish Sea west (Functional Unit 15) : Females Mean weight (kg) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0030 .0030 .0030 .0030 .0030 •0030 .0030 .0030 2 .0060 .0060 .0060 .0060 .0060 .0060 .0060 .0060 3 .0100 .0100 .0100 .0090 .0100 .0100 .0100 .0100 • 4 .0130 .0130 .0130 .0130 .0130 .0130 .0130 .0130 5 .0170 .0170 .0170 .0170 .0170 .0170 .0170 .0170 6 .0220 .0220 .0220 .0220 .0220 .0220 .0220 .0220 7 .0260 .0260 .0260 .0260 .0260 .0260 .0260 .0260 8 .0310 .0310 .0300 .0310 .0310 .0310 .0310 .0310 9 .0360 .0350 .0360 .0360 .0350 .0350 .0350 .0360 10 .0410 .0400 .0410 .0400 .0400 .0400 .0400 .0400 11 .0430 .0440 .0430 .0430 .0440 .0440 .0440 .0450 12 .0490 .0490 .0490 .0000 .0490 .0490 .0490 .0490 146 Table 5.11.15 VPA. Irish Sea west (Functional Unit 15) : Females Fishing mortality (F) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0238 .0279 .0295 .0381 .0199 .0201 .0081 .2000 2 .4634 .4968 .5731 .5583 .4532 .5138 .5329 .3000 3 .6272 .5962 .6804 .7548 .7700 .7909 .8785 .8800 4 .5911 .5023 .6313 .5098 .7607 .8538 .9769 .8386 5 .4948 .3468 .4389 .4169 .5505 .5691 .7674 .7048 6 .3899 .2120 .2966 .3178 .4636 .3856 .3926 .7323 7 .3893 .1815 .2433 .1922 .2549 .4228 .2854 .5463 8 .5489 .1552 .1937 .1947 .1467 .3204 .3477 .1998 9 .3737 .4541 .1255 .0965 .1785 .2296 .2124 .3000 10 1.0911 .2075 .7720 .1918 .1033 .3935 .2652 .2000 11 .6712 .2723 .3637 .1610 .1428 .3145 .2751 .2333 12 .6712 .2723 .3637 .1610 .1428 .3145 .2751 .2333 Table 5.11.16 VPA. Irish Sea west (Functional Unit 15): Females Population numbers (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 840732. 897343. 721447. 603992. 649586. 647670. 1146472. 75720. 2 549252. 608192. 646452. 518932. 430729. 471705. 470203. 842427. 3 277286. 255969. 274130. 269982. 219943. 202807. 209030. 204415. 4 117536. 121243. 115446. 113657. 103903. 83366. 75281. 71095. 5 46918. 53284. 60068. 50271. 55891. 39754. 29062. 23205. 6 23573. 23419. 30840. 31706. 27126. 26388. 18423. 11045. 7 9334. 13068. 15511. 18770. 18892. 13970. 14691. 10186. 8 3971. 5178. 8923. 9956. 12681, 11987. 7494. 9041. 9 3187. 1878. 3630. 6019. 6710. 8966. 7124. 4334. 10 587. 1796. 976. 2621. 4475. 4595. 5835. 4716. 11 397. 161. 1195. 369. 1772. 3304. 2538. 3664. 12 1437. 818. 2480. 910. 6058. 8434. 5661. 9051. • Table 5.11.17 VPA. Irish Sea west (Functional Unit 15): Females Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1991 Year, Yield, Fbar, 1SB, SSB, Log R 3- 8 1984, 3573.9, .5069, 12026.8, 6209.1, 13.64 1985, 3383.4, .3323, 12583.1, 6241 .9, 13 •71 1986, 4117.6, .4140, 12999.4, 6956.3, 13.49 1987, 3556.9, .3977, 11519.2, 6593.6, 13.31 1988, 3429.2, .4910, 11303.1, 6770.0, 13.38 1989, 3534.9, .5571 , 10932.5, 6159.3, 13.38 1990, 3431.3, .6081, 11715.1, 5454.4, 13.95 1991, 3401.7, .6503, 10385.8, 5104.0, 11.23 147 Table 5.11.18 Nephrops landings (tannes by Functional Unit plus other rectangles in Management Area (J) - (Vlla excluding rectangles 33E2-E5 ) Year FU14 FU15 Other rectangles Total 1982 897 9234 10131 1983 765 8898 9663 1984 619 7070 7689 1985 519 6430 6949 1986 686 8747 9433 1987 471 9257 9728 1988 497 8254 8751 1989 431 8065 8496 1990 630 8277 <1 8907 1991 (-) 837 9459 10296 Table 5.11.19 Total Nephrops landings (t) by country in Management Area (J) - (Vlla excluding rectangle 33E2-E5) Year UK Isle of Republic France Belgium TOTAL Man of Ireland 1982 5446 363 4235 87 0 10131 1983 5719 170 3747 27 <1 9663 1984 4775 169 2704 41 0 7689 1985 4913 3 1991 42 0 6949 1986 5929 7 3404 93 <1 9433 1987 5514 18 4141 55 0 9728 1988 5780 39 2870 62 0 8751 1989 6011 8 2458 19 0 8496 1990 6165 25 2709 8 0 8907 1991(-)6861 57 3366 12 <1 10296 • 148 Table 5.13.1 Porcupine Bank (Functional Unit 16) landings (in tonnes), by country, 1982-91 Year France Spain UK (a) UK (b) Ireland (c)Total 1982 358 3 931 0 0 ? 4 289 83 615 2 811 0 0 ? 3 426 84 1 067 2 504 38 0 ? 3 609 85 1 181 2 738 34 0 ? 3 953 86 1 060 1 462 47 0 ? 2 569 1987 609 1 677 150 3 ? 2 439 88 600 1 555 173 1 ? 2 329 89 324 1 417 16 1 350 2 108 90 336 1 349 23 6 169 1 883 91(-) 348 1 021 70 4 171 1 614 (- ) provisional (a) English vessels, landed in Spain and Ireland (b) English vessels, landed in UK (c) Prior to 1989 Irish Porcupine landings not distinguished from those of Aran Islands (see Table 5.13.10) Table 5.13.2 Porcupine Bank (Functional Unit 16) : total effort (all gears combined) and CPUE (in kg per fishing day - BHP / 100) for the two components of Spanish trawl fleet and combined, 1982-91 Year Total Nephrops Finfish Total effort trawl trawl CPUE 1982 137 883 118.5 20.7 28.5 83 107 643 97.7 18.5 26.1 84 113 535 94.7 16.6 22.1 85 115 331 74.6 18.5 23.7 86 95 269 61.8 10.9 15.4 1987 104 530 60.8 12.7 16.0 88 108 856 43.8 10.8 14.3 • 89 104 825 45.1 10.8 13.5 90 96299 35.5 11. 5 14.0 91(-) 85220 33.4 8.9 12.0 (-) provisional 149 Table 5.13.3 Porcupine Bank (Functional Uni t 16)' : effort (in days fishing) and LPUE (in kg/day) of French Nephrops trawlers, home port Saint Gue nole, 1982-91 Year Effort LPUE 1982 ? 950 83 359 868 84 748 760 85 783 752 86 591 802 1987 511 493 88 329 512 89 311 331 90 238 367 91 434 348 Table 5.13.4 Porcupine Bank (Functional Unit 16) : mean sizes (CL in mm) of male and female Nephrops in Spanish catches, 1982-91 Year Males Females 1982 40.9 34.8 83 40.8 34.0 84 39.7 33.1 85 38.7 33.5 86 40.8 34.9 1987 39.5 35.1 88 40.7 38.4 89 40.5 36.5 90 41.0 36.8 91 39.4 34.5 • 150 Table 5.13.5 VPA. Porcupine Bank (Functional Unit 16) : Males Catch (OOO's) at 'nominal age'. 1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 105. 49. 23. O. 39. 30. 10. 5. O. 3. O. 2 328" 3140. 2370. 4579. 6059. 1478. 2177. 707. 316. 775. 1126. 3 1434" 15439. 12298. 19573. 22871. 7939. 11053. 7557. 5590. 6684. 8080. 4 18871. 18028. 16332. 20818. 20922. 14246. 13208. 13427. 11532. 10006. 8350. 5 13324. 14450. 12646. 12470. 12199. 11126. 9358. 9471- 7320. 659" 5418. 6 5820. 8994. 7092. 5790. 5493. 5074. 3326. 3579. 2960. 2623. 2477. 7 2510. 4414. 3553. 3484. 2412. 1930. 986. 1708. 1042. 952. 1038. 8 1230. 2010. 1479. 1620. 1024. 731. 526. 814. 356. 397. 371- 9 476. 644. 442. 722. 413. 275. 363. 230. 109. 123. 200. 10 207. 354. 286. 229. 230. 92. 80. 99. 29. 42. 71- - 11 167. 313. 164. 155. 226. 66. 73. 72. 13. 29. 63. Table 5.13.6 VPA. Porcupine Bank (Functional Unit 16): Males Mean weight (kg) at 'nominal age' .1981-1991 Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0060 .0060 .0060 .0000 .0060 .0050 .0060 .0060 .0000 .0060 .0000 e 2 .0130 .0140 .0140 .0130 .0140 .0140 .0140 .0140 .0150 .0140 .0140 3 .0240 .0240 .0240 .0240 .0240 .0250 .0240 .0250 .0260 .0250 .0240 4 .0390 .0390 .0400 .0390 .0390 .0400 .0400 .0400 .0400 .0400 .0390 5 .0580 .0590 .0580 .0580 .0580 .0580 .0580 .0580 .0570 .0570 .0580 6 .0790 .0800 .0810 .0790 .0800 .0800 .0790 .0800 .0800 .0790 .0800 7 .1040 .1040 .1040 .1050 .1030 .1030 .1030 .1040 .1020 .1030 .1020 8 .1270 .1270 .1260 .1270 .1280 .1260 .1290 .1260 .1260 .1270 .1270 9 .1520 .1510 .1520 .1520 .1520 .1520 .1520 .1510 .1510 .1510 .1530 10 .1770 .1760 .1760 .1760 .1760 .1760 .1770 .1750 .1760 .1760 .1760 11 .2160 .2190 .2100 .2170 .2190 .2230 .2280 .2320 .2070 .2190 .2440 151 Table 5.13.7 VPA. POI'cupine Bank (Functional UnH 16) : Males Fishing mortality (F) at 'nominal age' . 1981-1991 F-at-age Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 .0010 .0004 .0002 .0000 .0005 .0005 .0002 .0001 .0000 .0005 .2000 2 .0376 .0362 .0262 .0542 .0993 .0249 .0427 .0164 .0073 .0133 .3000 3 .2138 .2477 .1935 .3103 .4121 .1824 .2612 .2037 .1736 .2098 .1861 4 .4045 .4535 .4493 .5775 .6395 .4903 .5183 .5808 .5426 .5312 .4383 5 .5015 .6247 .6733 .7475 .8148 .8665 .7051 .8947 .7402 .6966 .6215 6 .4718 .7650 .7323 .7687 .9078 1.0146 .7027 .6515 .8051 .6550 .6215 7 .5153 .8106 .8074 1.0354 .8860 1.0044 .5457 1.0109 .3974 .6679 .5937 8 .5715 1.0601 .7179 1.1645 1.0554 .7526 .8598 1.2844 .5952 .2584 .6014 9 .4907 .6780 .7128 .9772 1.1586 .9573 1.1289 1.2868 .5681 .4230 .2000 10 .5258 .8496 .7460 1.0590 1.0333 .9048 .8448 1.1940 .5202 .4498 .4650 11 .5258 .8496 .7460 1.0590 1.0333 .9048 .8448 1.1940 .5202 .4498 .4650 Table 5.13.8 VPA. Porcupine Bank (Functional Unit 16) : Males Population numbers (000' s) at 'nominal age' . 1981-1991 N-at-age Age 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1 119028. 123399. 116889. 86270. 80846. 70237. 58527. 58361. 79114. 5828. O. 2 98073. 97357. 100987. 95680. 70632. 66156. 57478. 47909. 4m8. 64m. 4770. 3 81899. 77327. 76868. 80537. 74203. 52364. 52827. 45090. 38585. 38832. 52330. 4 62172. 54145. 49420. 51861. 48348. 40232. 35722. 33309. 30113. 26556. 25776. ." 5 36967. 33969. 28166. 25818. 23831. 20880. 20174. 17417. 15257. 14329. 12782 • 6 16939. 18329. 14891. 11761. 10009. 8638. 7187. 8160. 5829. 5958. 5845. 7 6821. 8652. 6982. 5861. 4464. 3306. 2564. 2914. 3482. 2133. 2534. 8 3087. 3336. 3149. 2550. 1704. 1507. 991. 1216. 868. 1916. 896. 9 1343. 1427. 946. 1258. 651. 486. 581. 344. 276. 392. 1211. 10 553. 673. 593. 380. 388. 167. 153. 154. 78. 128. 210. 11 447. 594. 339. 258. 380. 121. 139. 111. 36. 88. 186. Table 5.13.9 VPA. Porcupine Bank (Functional Unit 16): Males Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1981-1991 Year, Yield, Fbar, TSB, SSB, Log R 3- 8 1981, 2918.3, .4464, 11361.7, 11361.7, 11.69 1982, 3632.2, .6603, 11328.9, 11328.9, 11.72 1983, 2997.4, .5956, 10218.9, 10218.9, 11.67 1984, 3277.1, .7673, 8879.0, 8879.0, 11.37 1985, 3129.1, .7859, 8251.6, 8251.6, 11.30 1986, 2204.0, .7185, 6758.5, 6758.5, 11.16 1987, 1885.0, .5988, 6129.6, 6129.6, 10.98 1988, 1920.4, .7710, 5704.4, 5704.4, 10.97 1989, 1440.9, .5424, 4787.7, 4787.7, 11. 28 1990, 1342.1, .5032, 4826.4, 4826.4, 8.67 1991, 1259.2, .5104, 4166.6, 4166.6, 152 Table 5.13.10 Aran Islands (Functional Unit 17) landings (in tonnes). by country, 1982-91 Year France Ireland (a) UK Total 1982 414 512 0 926 83 210 795 0 1005 84 131 267 0 398 85 324 1665 0 1989 86 207 838 0 1045 1987 147 1030 0 1177 88 62 691 0 753 89 14 814 0 828 90 27 317 1 345 91(-) 30 520 0 550 (-) Provisional (a) Prior to 1989 the Irish Aran landings presented are for Aran and the Porcupine Bank combined. • 153 Table 5.13.11 LCA. Aran Grounds (Functional Uni t 17) : Males Cohort Analysis Output. Reference period 1990-1991 LABEL = IR9091H eOHORT ANALYSIS L INFINITY = 60.0000 K = .1500 eOHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REMOVALS M OT FOT F Z NO. ATTAINING AVE. NO. IN SEA BIOMASS kg 18.0 1.0 .3000 .3253 .0000 .0001 .3001 35482.9 10996.1 44790.5 20.0 49.3 .3000 .3420 .0016 .0047 .3047 32183.1 10451.2 58700.5 22.0 193.8 .3000 .3604 .0071 .0196 .3196 28998.5 9872.8 74256.9 24.0 434.8 .3000 .3811 .0180 .0472 .3472 25842.8 9224.0 90668.5 26.0 938.8 .3000 .4042 .0451 .1115 .4115 22640.5 8430.1 106086.5 28.0 1607.8 .3000 .4303 .0937 .2178 .5178 19171.7 7394.5 117046.4 30.0 2445.3 .3000 .4600 .1872 .4071 .7071 15342.9 6024.4 118122.1 32.0 2282.5 .3000 .4941 .2508 .5075 .8075 11083.1 4515.2 108207.7 34.0 1737.3 .3000 .5336 .2918 .5468 .8468 7436.9 3192.9 92427.2 36.0 1241.0 .3000 .5801 .3369 .5808 .8808 4733.2 2149.8 74384.0 38.0 885.0 .3000 .6354 .4198 .6607 .9607 2839.6 1350.4 55327.2 40.0 546.0 .3000 .7024 .4998 .7116 1.0116 1542.2 775.4 37301.1 42.0 277.0 .3000 .7852 .5297 .6746 .9746 757.8 415.8 23307.7 _ 44.0 107.0 .3000 .8902 .4260 .4785 .7785 352.5 226.4 14683.1 46.0 44.0 .3000 1.0277 .3442 .3349 .6349 176.3 133.1 9923.0 48.0 25.0 .3000 1.2155 .3957 .3256 .6256 91.8 78.1 6661.5 50.0 11.0 .3000 1.4876 .3862 .2596 .5596 42.9 43.3 4200.1 52.0 6.0 .3000 1.9179 .5596 .2918 .5918 18.7 21.4 2347.3 54.0 3.0 .3000 .3000 .6000 6.0 21.4 2347.3 Table 5.13.12 LCA. Aran Grounds (Functional Unit 17): Females Cohort Analysis Output. Reference period 1990-1991 LABEL = IRF eOHORT ANALYSIS LOUER eURVE LINF= 60.0000 K= •1500 • UPPER eURVE LINF= 50.0000 K= .1000 TRANSITION LENGTH= 24.0000 eOHORT ANALYSIS BY POPE'S APPROXIMATION SIZE MM REMOVALS M OT FOT F Z NO. ATTAINING AVE. NO. IN SEA BIOMASS kg 16.0 4.0 .3000 .3101 .0002 .0006 .3006 20809.4 6162.0 18380.5 18.0 7.1 .3000 .3253 .0004 .0012 .3012 18956.8 5873.6 24351.4 20.0 25.5 .3000 .3420 .0016 .0046 .3046 17187.6 5581.7 31120.2 22.0 351.5 .3000 .3604 .0242 .0673 .3673 15487.5 5228.7 38161.0 24.0 959.0 .2000 .3811 .0763 .2001 .4001 13567.2 4795.0 44792.0 26.0 1801.8 .2000 .8701 .1848 .2124 .4124 11648.5 8516.3 99907.7 28.0 2275.3 .2000 .9531 .3676 .3857 .5857 8136.4 5942.6 86136.1 ~O.O 2059.8 .2000 1.0536 .6764 .6420 .8420 4655.9 3252.3 57428.8 32.0 952.3 .2000 1.1778 .8180 .6945 .8945 1917.5 1396.1 29664.8 34.0 400.8 .2000 1.3353 1.1553 .8652 1.0652 668.6 476.3 12046.2 36.0 92.0 .2000 1.5415 1.0957 .7108 .9108 161.2 133.5 3981.2 38.0 16.0 .2000 1.8232 .6633 .3638 .5638 39.6 45.1 1571.6 40.0 3.0 .2000 2.2314 .3075 .1378 .3378 14.2 22.2 896.9 42.0 4.0 .2000 .3000 .5000 6.7 .0 .0 154 Table 5.13.13 Republic of Ireland coast (Functional Units 18 and 19) : landings (in tonnes) by the Republic of Ireland, 1982-91 Year FU 18 FU 19 1982 2 307 83 4 488 84 90 408 85 22 673 86 8 474 1987 9 725 88 13 601 89 11 652 90 (-) 5 569 91 (. ) 31 167 (- ) provisional • 155 Table 5.13.14 Nephrops landings (tonnes) by Functional Unit plus other rectangles in Management Area (VIIb,c,j,k) - (Area L) Year FU16 FU17 FU18 FU19 Other rectangles Total 1982 4289 926 2 307 237 5761 1983 3426 1005 4 488 174 5097 1984 3609 398 90 408 266 4771 1985 3953 1989 22 673 208 6845 1986 2569 1045 8 474 135 4231 1987 2439 1177 9 725 170 4520 1988 2329 753 13 601 187 3883 1989 2108 828 11 652 143 3742 1990 1883 345 5 569 114 2916 1991(-) 1614 550 31 167 200 2562 • Table 5.13.15 Total Nephrops landings (t) by country in Management Area VIIb,c,j,k (Area L) Year Spain France Republic of UK TOTAL Ireland 1982 4159 772 821 9 5761 1983 2979 825 1287 6 5097 1984 2690 1198 765 118 4771 1985 2889 1505 2360 91 6845 1986 1542 1267 1320 102 4231 1987 1735 756 1764 265 4520 1988 1617 662 1305 299 3883 1989 1505 338 1827 72 3742 1990 1436 363 1060 57 2916 1991 1152 378 889 143 2562 • 156 Table 5.14.1 Celtie Sea (Funetional Units 20, 21 and 22) landings (in tonnes), byeountry, 1982-91 Franee Ireland UK Belgium Year FU 20-22 FU 22 FU 20-22 FU 20-22 Total 1982 2 917 87 23 ? 3 027 83 3 667 510 65 <1 4 242 84 3 653 253 36 2 3 944 85 3 599 222 3 o 3 824 86 2 638 167 <1 o 2 805 1987 2 806 329 <1 <1 3 135 88 2 672 239 2 o 2 913 89 3 083 784 15 o 3 882 90 3 762 528 15 <1 4 304 91 2 652 412 13 2 3 079 (-) provisional Table 5.14.2 Celtie Sea (Funetional Units 20, 21 and 22) : effort (in days fishing) and LPUE (in kg/day) of Freneh Nephrops trawlers, home port Saint • Guenole, 1982-91. Estimated total effort in hours fished and LPUE in Kg/hour. Year Effort LPUE Estimated LPUE (days) (kg/day) Total eff. 1982 ? 218 83 5 743 242 84 4 169 268 247637 15 85 4 106 282 245600 15 86 4 205 233 208263 13 1987 4 656 263 204708 14 88 4 595 256 183203 15 89 4 953 240 210374 15 90 5 460 230 282290 13 91 (-) 4 250 181 • (-) provisional Table 5.14.3- Celtie Sea (Funetional Units 20, 21 and 22) mean sizes (CL in mm) of male and female Nephrops in Freneh landings, 1982-91 Year Males Females 1982 ? ? 83 ? ? 84 39.0 36.3 85 39.2 36.9 86 39.3 37.5 1987 38.8 35.1 88 35.7 34.7 89 38.9 36.0 90 39.7 35.4 91 38.7 34.6 157 Table 5.14.4 VPA. Celtic Sea (Functional Unit 20-22): Males Catch (OOO's) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 6696. 6073. 3904. 6237. 8435. 8826. 8186. 2 43568. 38275. 24417. 42131. 67556. 56672. 50822. 3 30192. 28697. 17194. 28470. 34513. 42542. 36320. 4 15788. 14567. 8753. 13299. 10120. 22636. 20035. 5 6568. 6756. 4198. 5236. 3920. 8690. 10522. 6 5504. 4862. 3005. 3221. 1864. 3420. 4994. 7 1311. 1122. 702. 1705. 894. 1660. 2187. 8 O. O. O. 1458. 746. 1368. 1397. • Table 5.14.5 VPA. Celtic Sea (Functional Unit 20-22): Males Mean weight (kg) at 'nominal age' .1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0110 .0110 .0110 .0110 .0110 .0110 .0110 2 .0190 .0190 .0190 .0190 .0190 .0190 .0190 3 •0330 .0330 .0330 .0330 .0320 .0330 .0330 4 .0520 .0520 .0520 .0510 .0520 .0510 .0520 5 .0720 .0720 .0720 .0730 .0720 .0720 .0720 • 6 .0990 .0990 .0990 .0950 .0950 .0940 .0940 7 .1060 .1060 .1060 .1170 .1170 .1170 .1170 8 .0000 .0000 .0000 .1380 .1370 .1370 .1370 158 Table 5.14.6 VPA. Celtic Sea (Functional Unit 20-22): Males Fishing mortality CF) at 'nominal age' . 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0376 .0322 .0146 .0215 .0349 .0391 .0336 2 .3793 .3476 .1943 .2393 .3n6 .3852 .3671 3 .4860 .5253 .2909 .4092 .3540 .4925 .5196 4 .4663 .5230 .3366 .4328 .2789 .4701 .5180 5 .4707 .4210 .3129 .3897 .2440 .4639 .4725 6 .9763 .9025 .3n7 .4763 .2610 .3920 .6094 7 .6370 .6146 .3419 .4323 .2610 .4414 .5326 8 .6370 .6146 .3419 .4323 .2610 .4414 .5326 Table 5.14.7 VPA. Celtic Sea (Functional Unit 20-22): Males • Population numbers (OOO's) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 209658. 221995. 311984. 339760. 284090. 2662n. 286391. 2 158280. 149582. 159254~ 22n63. 246333. 203232. 189703. 3 89708. 80244. 78272. 97142. 132817. 125093. 102420. 4 48470. 40874. 35152. 43347. 4n96. 69055. 56628. 5 20016. 22524. 17947. 18598. 20829. 26790. 31969. 6 9980. 9261- 10952. 9723. 9330. 12090. 12479. 7 3171- 2785. 2782. 5561. 4473. 5324. 6052. 8 O. O. O. 4758. 3735. 4389. 3865. Table 5.14.8 VPA. Celtic Sea (Functional Unit 20-22): Males Yield (tonnes),Fbar,Total stock biomass (tannes), spawning stock biomass (tannes), Ln recruitrnent 1984-1990 Year, Yietd, Fbar, 15B, 5SB, log R 2- 6 1984, 3875.5, .5557, 13559.8, 13559.8, 12.25 1985, 3585.2, .5439, 12891.3, 12891.3, 12.31 1986, 2203.5, .3025, 13539.9, 13539.9, 12.65 1987, 3598.9, .3895, 17069.8, 17069.8, 12.74 1988, 3683.2, .3031, 17962.1, 17962.1, 12.56 1989, 5081.9, .4407, 18729.9, 18729.9, 12.49 1990, 4987.4, .4973, 17791.5, 1n91.5, 12.57 159 Table 5.14.9 VPA. Celtic Sea (Functional Unit 20-22) : Females Catch (OOO's) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 4887. 7553. 6178. 2197. 2083. 2035. 2722. 2 10871. 16789. 13663. 5125. 4432. 4744. 6225. 3 7419. 11349. 9034. 3661. 3714. 3186. 4432. 4 6809. 11693. 8226. 3286. 2884. 3011. 3981. 5 5803. 10064. 6255. 2568. 1823. 2780. 2983. 6 4728. 5727. 3710. 1994. 1618. 2050. 2443. 7 3917. 4274. 2806. 1581. 657. 1598. 1630. 8 3222. 3936. 2953. 1213. 766. 1055. 1278. 9 2466. 3580. 2709. 781. 413. 879. 975. 10 6991. 14301. 10848. 2300. 2154. 2707. 3566. • Table 5.14.10 VPA. Celtic Sea (Functional Unit 20-22): Females Mean weight (kg) at 'nominal age' .1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0100 .0100 .0100 .0100 .0100 .0100 .0100 2 .0140 .0140 .0140 .0140 .0140 .0140 .0140 3 .0180 .0180 .0180 .0180 .0180 .0170 .0180 4 .0210 .0220 .0210 .0210 .0210 .0220 .0210 5 .0260 .0260 .0260 .0260 .0260 .0260 .0260 6 .0290 .0290 .0290 .0290 .0290 .0290 .0290 7 .0340 .0340 .0340 .0340 .0340 .0340 .0340 8 .0380 .0380 .0380 .0380 .0370 .0380 .0380 9 .0420 .0420 .0410 .0410 .0410 .0410 .0420 10 .0550 .0590 .0600 .0540 .0630 .0580 .0540 160 ---~ ------ Table 5.14.11 VPA. Celtic Sea (Functional Unit 20-22): Females Fishing mortality (F) at 'nominal age' . 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 .0601 .1099 .1216 .0471 .0469 .0505 .0783 2 .1742 .3182 .3143 .1487 .1337 .1513 .2272 3 .1498 .2n4 .2829 .1293 .1530 .1342 .2061 4 .1740 .3711 .3323 .1573 .1424 .1786 .2469 5 .2355 .4182 .3478 .1634 .1228 .1985 .2696 6 .2363 .3846 .2671 .1m .1469 .1974 .2684 7 .1894 .3478 .3298 .1738 .0814 .2115 .2381 8 .1931 .2951 .4316 .2314 .1193 .1814 .2612 9 .2050 .3402 .3401 .1925 .1150 .1953 .2540 10 .2050 .3402 .3401 .1925 .1150 .1953 .2540 Table 5.14.12 VPA. Celtic Sea (Functional Unit 20-22): Females • Population numbers (OOO's) at 'nominal age'. 1984-1990 Age 1984 1985 1986 1987 1988 1989 1990 1 96898. 83769. 62253. 55170. 52591. 47805. 41757. 2 74815. 67600. 55598. 40837. 38989. 37176. 33671- 3 586n. 51462. 40260. 33242. 28816. 27927. 26163. 4 46898. 41356. 31928. 24840. 23916. 20246. 19993. 5 30396. 32264. 23361. 18750. 173n. 16982. 13865. 6 24692. 19665. 17387. 13508. 13037. 12583. 11401. 7 24966. 15962. 10959. 10899. 9263. 9216. 8457. 8 201n. 16913. 9230. 6452. 7499. 6992. 6107. 9 14630. 13618. 10309. 4908. 4191. 5450. 4775. 10 41479. 54407. 41286. 14443. 21840. 167n. 17467. Table 5.14.13 VPA. Celtic Sea (Functional Unit 20-22): Females Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1990 Year, Yield, Fbar, TS8, SSB, log R 2- 8 1984, 1509.2, .1932, 10075.2, 9106.2, 11.48 1985, 2488.8, .3446, 9996.7, 9159.1, 11.34 1986, 1828.2, .3294, 7530.9, 6908.3, 11.04 1987, 609.3, .1687, 4719.5, 4167.8, 10.92 1988, 507.9, .1285, 5062.7, 4536.8, 10.87 1989, 626.3, .1790, 4500.7, 4022.6, 10.77 1990, 763.7, .2454, 4134.2, 3716.6, 10.64 161 Table 5.14.14 Nephrops landings (tannes by Functional Unit plus other rectangles in Management Area (M) - (Vllf,g,h, & Vlla rectangles 33E2-E5) Year FU20+21 +22 Other rectangles Total 1982 3027 4 3031 1983 4242 8 4250 1984 3944 1 3945 1985 3824 0 3824 1986 2805 0 2805 1987 3135 235 3370 1988 2911 155 3066 1989 3882 98 3980 1990 4304 75 4379 1991 3079 2 3081 Table 5.14.15 Total Nephrops landings (t) by country in Management • Area (M) - (Vllf,g,h & Vlla rectangles 33E2-E5) Year France Republic UK Belgium Total of Ireland 1982 2917 87 27 ? 3031 1983 3667 510 73 ? 4250 1984 3653 253 39 ? 3945 1985 3599 222 3 ? 3824 1986 2638 167 <1 0 2805 1987 3041 329 <1 0 3370 1988 2825 239 2 0 3066 1989 3185 784 11 <1 3980 1990 3832 528 18 1 4379 1991 2652 412 15 2 3081 162 ------1 Table 5.15.1 Bay of Biscay (Functional Units 23 and 24) landings (in tonnes) by the French fleet, 1982-91 Year France France Belgium Total FU 23 FU 24 23 & 24 1982 4 392 298 0 4 690 83 5 566 342 0 5 908 84 4 485 198 0 4 683 85 4 281 312 0 4 593 86 3 968 367 0 4 335 1987 5 074 473 0 5 597 88 6 019 658 0 6 745 89 4 600 630 0 5 295 90 4 603 358 1 4 961 91 (.) 4 352 401 <1 4 753 (. ) provisional Table 5.15.2 Bay of Biscay North (Functional Unit 23) • effort (in days fishing) and LPUE (in kg/day) of French Nephrops trawlers, home port Lesco nil, 1982-91. Estimated total effort in hours fished and LPUE in Kg/hr. Year Effort LPUE Estimated LPUE (days) kg/day total eff kg/hr 1982 6 709 102 83 6 481 109 84 5 673 87 470991 10 85 5 603 88 568815 8 86 5 137 95 534358 8 1987 5 673 106 611434 9 88 5 433 119 757141 9 89 5 449 95 713493 7 90 4 929 87 611320 8 91 4 588 84 584000 8 Table 5.15.3 Bay of Biscay (Functional Units 23 and 24) mean sizes (CL in mm) of male and female Nephrops in French landings, 1982-91 Year Males Females 1982 ? ? 83 ? ? 84 26.9 27.0 85 26.1 26.7 86 27.3 27.7 1987 28.8 26.3 88 28.5 26.2 89 29.2 26.8 90 31.2 27.9 91 30.7 28.4 163 Table 5.15.4 VPA. Bay of Biscay (Functional Unit 23&24): Males Catch (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 16037. 17251. 13900. 24429. 28940. 19545. 10168. 7899. 2 84318. 105301. 71977. 134938. 164980. 109216. 62801. 62263. 3 57210. 65533. 56941. 92954. 101413. 68852. 48587. 66428. 4 27349. 23104. 24992. 38009. 45249. 30663. 33952. 29296. 5 12252. 8106. 10559. 14723. 16831. 14048. 19027. 14022. 6 4157. 3668. 3907. 6037. 7031- 5232. 7381. 6670. 7 1015. 1778. 1256. 2584. 2679. 2909. 3658. 2956. 8 341. 804. 521. 1075. 973. 1519. 2008. 1145. 9 188. 684. 402. 1184. 1091. 1651. 1108. 839. • Table 5.15.5 VPA. Bay of Biscay (Functional Unit 23&24): Males Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0040 .0040 .0040 .0040 .0040 .0040 .0040 .0040 2 .0080 .0080 .0080 .0080 .0080 .0080 .0080 .0080 3 .0150 .0150 .0150 .0150 .0150 .0150 .0160 .0150 4 .0260 .0260 .0260 .0260 .0260 .0260 .0270 .0260 5 .0390 .0390 .0390 .0390 .0390 .0380 .0390 .0390 6 .0530 .0540 .0530 .0540 .0540 .0540 .0540 .0540 7 .0690 .0700 .0700 .0700 .0700 .0710 .0700 .0700 8 .0870 .0880 .0880 .0870 .0870 .0880 .0880 .0880 9 .1020 .1010 .1010 .1240 .1270 .1250 .1180 .1190 164 Table 5.15.6 VPA. Bay of Biscay (Functional Unit 23&24): Males Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0341 .0335 .0235 .0434 .0664 .0467 .0333 .0375 2 .3070 .3635 .2122 .3701 .5111 .4254 .2310 .3250 3 .4712 .4707 .3854 .5258 .6010 .4719 .3837 .4604 4 .5989 .3985 .3714 .5481 .6046 .4123 .5125 .4n8 5 .6143 .4001 .3601 .4417 .5729 .4301 .5550 .4679 6 .5476 .4224 .3859 .4066 .4431 .3944 .4791 .4341 7 .2955 .5467 .2794 .5429 .3579 .3739 .6051 .4047 8 .4854 .4559 .3415 .4633 .4576 .3991 .5459 .4352 9 .4854 .4559 .3415 .4633 .4576 .3991 .5459 .4352 Table 5.15.7 VPA. Bay of Biscay (Functional Unit 23&24): Males • Population numbers (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 553580. 605114. 691503. 664381. 520824. 495594. 359573. 2484n. 2 366433. 396362. 433499. 500366. 471261. 361061. 350404. 257667. 3 174209. 199704. 204141. 259747. 256019. 209403. 174800. 206041. 4 69221. 80562. 92393. 102864. 113734. 103985. 96767. 88223. 5 30432. 28173. 40063. 47211. 44044. 46031. 51005. 42935. 6 11258. 12197. 13988. 20704. 22486. 18399. 22180. 21689. 7 4559. 4823. 5922. 7045. 10213. 10694. 9187. 10176. 8 1013. 2513. 2068. 3318. 3032. 5289. 5451. 3716. 9 559. 2139. 1593. 3653. 3400. 5750. 3007. 2723. Table 5.15.8 VPA. Bay of Biscay (Functional Unit 23&24): Males Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1991 Year, Yield, Fbar, TSB, SSB, Log R 2- 7 1984, 3124.9, .4724, 11802.0, 11802.0, 13.22 1985, 3273.7, .4336, 13213.7, 13213.7, 13.31 1986, 2928.5, .3324, 14759.6, 14759.6, 13.45 1987, 4881.1, .4725, 17425.2, 17425.2, 13.41 1988, 5580.0, .5151, 16993.2, 16993.2, 13.16 1989, 4144.8, .4180, 15401.8, 15401.8, 13.11 1990, 3941.2, .4611, 14315.6, 14315.6, 12.79 1991, 3602.4, .4283, 12648.8, 12648.8, 12.42 165 Table 5.15.9 VPA. Bay of Biscay (Functional Unit 23&24): Females Catch (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 3049. 2556. 2259. 1413. 1350. 1603. 1943. 1667. 2 108069. 101517. 88148. 60491. 58443. 66379. 55776. 25528. 3 91446. 91638. 74081. 66117. 80983. 71388. 50669. 48936. 4 46078. 36978. 40935. 31m. 40957. 29833. 29940. 38972. 5 17452. 13850. 16724. 8009. 12332. 9997. 11697. 13992. 6 4897. 4425. 5689. 2128. 3550. 4369. 5345. 4470. 7 1472. 1671. 1730. 1043. 1632. 2102. 1970. 1674. 8 441. 669. 616. 490. 812. 1027. 846. 723. 9 198. 269. 262. 184. 395. 501. 380. 328. 10 303. 539. 485. 703. 622. 1584. 594. 693. • Table 5.15.10 VPA. Bay of Biscay (Functional Unit 23&24): Females Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0030 .0030 .0030 .0030 .0030 .0030 .0030 .0030 2 .0060 .0060 .0060 .0060 .0060 .0060 .0060 .0060 3 .0100 .0100 .0100 .0100 .0100 .0100 .0100 .0110 4 .0160 .0160 .0160 .0160 .0160 .0160 .0170 .0160 5 .0230 • .0230 .0230 .0230 .0230 .0230 .0230 .0230 6 .0310 .0310 .0310 .0310 .0310 .0310 .0310 .0310 7 .0380 .0390 .0380 .0390 .0390 .0390 .0390 .0390 8 .0470 .0470 .0470 .0470 .0470 .0470 .0470 .0470 9 .0540 .0540 .0540 .0550 .0550 .0540 .0540 .0540 10 .0710 .0740 .0730 .0820 .0800 .0780 .0710 .0760 166 Table 5.15.11 VPA. Bay of Biscay (Functional Unit 23&24): Females Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0070 .0061 .0058 .0037 .0036 .0057 .0144 .0059 2 .3602 .3763 .3313 .2363 .2326 .2750 .3108 .2961 3 .6461 .6783 .5936 .5041 .6479 .5593 .3934 .5604 4 .7720 .6836 .8734 .6327 .7862 .6047 .5524 .6868 5 .8030 .6421 .9056 .4655 .6209 .5049 .5796 .6243 6 .6621 .5522 .6906 .2968 .4383 .5320 .6395 .5204 7 .5465 .5681 .4937 .2858 .4410 .5764 .5572 .4780 8 .4253 .5893 .4805 .2817 .4255 .6325 .5516 .4630 9 .5444 .5696 .5546· .2879 .4347 .5800 .5825 .4869 10 .5444 .5696 .5546 .2879 .4347 .5800 .5825 .4869 Table 5.15.12 VPA. Bay of Biscay (Functional Unit 23&24): Females • Population numbers (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 504614. 487405. 449090. 439082. 429996. 325601. 156743. 326889. 2 409873. 371203. 358878. 330750. 324065. 317387. 239831. 114445. 3 218896. 211790. 188745. 190891. 193457. 190246. 178592. 130209. 4 97287. 84989. 79623. 77227. 85414. 74976. 80550. 89273. 5 35880. 33303. 31782. 24627. 30388. 28828. 30341. 34343. 6 11516. 11908. 12982. 9519. 11454. 12099. 12890. 12590. 7 3993. 4400. 5078. 4821. 5241. 5474. 5265. 5038. 8 1459. 1713. 1847. 2296. 2684. 2498. 2279. 2234. 9 538. 706. 704. 846. 1283. 1299. 983. 972. 10 825. 1416. 1302. 3231. 2021. 4107. 1535. 2057• Table 5.15.13 VPA. Bay of Biscay (Functional Unit 23&24): Females • Yield (tannes),Fbar,Tatal stack biomass (tonnes), spawning stock biomass (tannes), Ln recruitment 1984-1991 Year, Yield, Fbar, TSB, SSB, log R 2- 7 1984, 2971.4, .6317, 9208.8, 9208.8, 13.13 1985, 2731.5, .5834, 8697.3, 8697.3, 13.10 1986, 2636.7, .6480, 8208.2, 8208.2, 13.01 1987, 1918.4, .4035, 7915.2, 7915.2, 12.99 1988, 2386.9, .5278, 8152.4, 8152.4, 12.97 1989, 2240.5, .5087, 7742.7, 7742.7, 12.69 1990, 1970.2, .5055, 6636.4, 6636.4, 11.96 1991, 1950.0, .5277, 6218.4, 6218.4, 12.70 167 Table 5.15.14 Nephrops landings (tonnes) by Functional Unit plus other rectangles in Management Area (N) - (Vllla.b) Year F1J23 F1J24 Other rectangles Total 1982 4392 298 4690 1983 5566 342 5908 1984 4485 198 4683 1985 4281 312 4593 1986 3968 367 99 4434 1987 5074 473 114 5661 1988 6019 658 137 6814 1989 4600 630 142 5372 1990 4603 358 142 5103 1991 4352 401 55 4808 Table 5.15.15 Total Nephrops landings (t) by country in Management • Area (N) - (Vllla,b) Year France Spain Belgium TOTAL 1982 4690 ? ? 4690 1983 5908 ? ? 5908 1984 4683 ? ? 4683 1985 4593 ? ? 4593 1986 4335 99 0 4434 1987 5597 64 0 5661 1988 6745 69 0 6814 1989 5295 77 0 5372 1990 5015 87 1 5049 1991 4753 55 <1 4808 • 168 Table 5.16.1 North Galicia (Functional Unit 25) : landings (in tannes) by the Spanish fleet, 1982-91 Year Spain Total 1982 431 431 83 430 430 84 514 514 85 477 477 86 364 364 1987 412 412 88 445 445 89 376 376 90 289 289 91 416 416 (-) provisional Table 5.16.2 North Galicia (Functional Unit 25) : effort (in days fishing) and CPUE (in kg per day BHP / 100) of Spanish "bacas", home port • La Coruna 1982-91 Year Effort CPUE 1982 7 698 10.1 83 6 343 12.2 84 6 260 14.7 85 6 015 14.1 86 5 017 11. 4 1987 4 266 15.4 88 5 246 13.2 89 5 753 10.1 90 5 710 6.7 91 (-) 5 135 12.5 (- ) provisional • Table 5.16.3 North Galicia (Functional Unit 25) : mean sizes (CL in mm) of male and female Nephrops in Spanish catches, 1982-91 Year Males Females 1982 36.9 35.2 83 34.7 32.2 84 35.2 32.0 85 35.8 33.1 86 35.1 32.1 1987 37.2 35.6 88 37.9 36.0 89 40.9 38.7 90 37.5 39.4 91 34.8 33.3 169 Table 5.16.4 VPA. North Galicia (Functional Unit 25): Males Catch (000'5) at 'nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 72. 134. 149. 43. 10. O. 4. 34. 2 2680. 1765. 1552. 866. 566. 82. 347. 2179. 3 4606. 2953. 2682. 1722. 2684. 954. 1462. 3235. 4 1847. 1923. 1561. 1525. 2557. 1292. 1048. 1591. 5 835. 826. 589. 682. 1311. 924. 440. 633. 6 561. 345. 144. 368. 202. 464. 152. 179. 7 125. 76. 43. 58. 56. 149. 53. 36. 8 30. 34. 6. 10. 12. 65. 28. 6. 9 5. 9. 3. 10. 9. 16. 6. 4. 10 6. 16. 4. 9. 23. 25. 13. 5. • Table 5.16.5 VPA. North Galicia (Functional Unit 25): Males Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0110 .0090 .0090 .0100 .0100 .0000 .0100 .0100 2 .0180 .0180 .0180 .0170 .0200 .0200 .0190 .0190 3 .0280 •0290 .0290 .0300 .0300 .0300 .0290 .0280 4 .0420 .0440 .0440 .0430 .0440 .0450 .0430 .0430 5 .0620 .0620 .0600 .0620 .0620 .0620 .0620 .0620 6 .0850 • .0830 .0800 .0820 .0830 .0840 .0830 .0820 7 .1030 .1030 .1040 .1020 .1020 .1050 .1060 .1030 8 .1210 .1270 .1210 .1240 .1250 .1240 .1240 .1220 9 .1520 .1470 .1620 .1520 .1550 .1480 .1490 .1490 10 .1740 .2350 .1620 .2010 .2090 .1920 .2120 .2120 170 Table 5.16.6 VPA. North Galicia (Functional Unit 25): Males Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0054 .0110 .0163 .0068 .0012 .0000 .0001 .2000 2 .2852 .1763 .1696 .1236 .1148 .0126 .0305 .0872 3 .7371 .5834 .4407 .2875 .6802 .2873 .3231 .4311 4 .8387 .8097 .7141 .4852 .9116 .8467 .5877 .7009 5 .9228 1.2481 .6318 .8111 1.0494 1.0654 .8073 .8853 6 1.6288 1.4217 .7618 1.1006 .6050 1.5853 .4889 .9583 7 1.2175 1.1616 .6694 .8230 .4679 1.3373 .7972 .2000 8 1.1367 1.5242 .2181 .3153 .4011 1.n10 1.0620 .2000 9 1.32n 1.3692 .5498 .7463 .4913 1.5645 .7827 .4528 10 1.32n 1.3692 .5498 .7463 .4913 1.5645 .7827 .4528 Table 5.16.7 VPA. North Galicia (Functional Unit 25): Males • Population numbers (OOO's) at 'nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 14745. 13520. 10184. 7065. 8792. 15564. 35098. 203. 2 11860. 12007. 10949. 8203. 5745. 7189. 12743. 28732. 3 9628. 7301. 8241. 7566. 5935. 4193. 5812. 10118. 4 3541. 3m. 3335. 4343. 4646. 2461. 2576. 3445. 5 1506. 1253. 1374. 1337. 2189. 1529. 864. 1172. 6 750. 490. 295. 598. 486. 627. 431. 316. 7 191. 120. 97. 113. 163. 217. 105. 217. 8 48. 46. 31. 41. 40. 84. 47. 39. 9 7. 13. 8. 20. 24. 22. 12. 13. 10 9. 23. 10. 19. 65. 34. 25. 15 • • . Table 5.16.8 VPA. Narth Galicia (Functional Unit 25): Males Yield (tonnes),Fbar,Total stock biomass (tannes), spawning stock biomass (tonnes), Ln recruitment 1984-1991 Year, Yield, Fbar, 1SB, SSB, log R 2- 6 1984, 373.3, .8825, 979.3, 979.3, 9.60 1985, 300.3, .8478, 859.5, 859.5, 9.51 1986, 228.9, .5436, 797.2, 797.2, 9.23 1987, 215.4, .5616, n9.2, 779.2, 8.86 1988, 315.8, .6722, 800.3, 800.3, 9.08 1989, 215.4, .7595, 570.8, 570.8, 9.65 1990, 146.7, .4475, 985.8, 985.8, 10.47 1991, 260.9, .6126, 1110.2, 1110.2, 5.31 171 Table 5.16.9 VPA. North Galicia (Functional Unit 25): Females Catch (OOO's) at 'nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 265. 434. 312. 187. 6. O. 88. 84. 2 2216. 1892. 2159. 1055. 658. 96. 814. 2009. 3 1924. 1n1. 1531. 1790. 1246. 1001. 1231. 2005. 4 358. 914. 557. 1184. 707. 1200. m. 613. 5 223. 306. 179. 428. 351. 625. 475. 222. 6 32. 133. 46. 248. 120. 236. 199. 92. 7 6. 70. 37. 169. 103. 95. 61. 51. 8 2. 33. 18. 36. 28. 45. 25. 22. 9 3. 11. 1. 22. 11. 18. 9. 12. 10 1- 4. 1. 10. 6. 6. 4. 5. 11 O. 13. 1. 9. 3. 10. 5. 4. • Table 5.16.10 VPA. North Galicia (Functional Unit 25): Females Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0110 .0110 .0110 .0120 .0120 .0000 .0110 .0120 2 .0180 .0180 •0180 .0180 .0200 .0210 .0180 .0190 3 .0280 .0280 .0280 .0290 .0280 .0300 .0290 .0280 4 .0400 .0410 .0400 .0400 .0410 .0420 .0410 .0400 • 5 .0540 .0550 .0560 .0550 .0560 .0550 .0550 .0550 6 .0670 .0700 .0670 .0710 .0700 .0690 .0690 .0690 7 .0850 .0830 .0870 .0820 .0830 .0820 .0820 .0830 8 .0900 .0970 .0910 .0930 .0930 .0980 .0970 .0960 9 .1160 .1060 .1110 .1140 .1120 .1070 .1070 .1110 10 .1160 .1240 .1240 .1160 .1190 .1220 .1230 .1170 11 .0000 .1490 .1300 .1450 .1360 .1470 .1390 .1480 172 Table 5.16.11 VPA. North Galicia (Functional Unit 25): Females Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0297 .0451 .0428 .0373 .0014 .0000 .0055 .2000 2 .3906 .3028 .3275 .1982 .1785 .0255 .1195 .1658 3 .6033 .6249 .4288 .4965 .3789 .4487 .5154 .4m 4 .3334 .6544 .4074 .7005 .3724 .7724 .7584 .5277 5 .5018 .5317 .2513 .6346 .4609 .6628 .8283 .5090 6 .1635 .6419 .1400 .6542 .3637 .6509 .4578 .3651 7 .0851 .6406 .3650 1.0789 .6338 .5488 .3430 .2000 8 .0963 .7945 .3272 .7346 .5058 .6350 .2749 .2000 9 .2750 1.2319 .0422 .8473 .5065 .6974 .2597 .2000 10 .1522 .8890 .2448 .8869 .5487 .6270 .2925 .2000 11 .1522 .8890 .2448 .8869 .5487 .6270 .2925 .2000 Table 5.16.12 VPA. North Galicia (Functional Unit 25): Females • Population numbers (OOO's) at 'nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 10005. 10839. 8226. 5615. 5126. 9717. 17767. 512. 2 7513. 7951. 8483. 6452. 4429. 4191. 7955. 14467. 3 4639. 4162. 4809. 5006. 4333. 3033. 3345. 5780. 4 1385. 2078. 1824. 2564. 2494. 2429. 1586. 1635. 5 618. 813. 884. 994. 1042. 1407. 918. 608. 6 233. 306. 391. 563. 431. 538. 594. 328. 7 86. 162. 132. 278. 240. 245. 230. 308. 8 23. 65. 70. 75. 77. 104. 116. 133. 9 12. 17. 24. 41. 29. 38. 45. 72. 10 11. 7. 4. 19. 14. 15. 16. 29. 11 O. 23. 3. 17. 7. 24. 23. 21. • Table 5.16.13 VPA. North Galicia (Functional Unit 25): Females Yield (tonnes).Fbar.Total stock biomass (tonnes), spawning stock biomass (tonnes). Ln recruitment 1984-1991 Year. Yield, Fbar, 1SB, SSB, log R 2- 6 1984, 126.3, .3985, 491.6, 491.6, 9.21 1985, 164.6, .5511, 556.2, 556.2, 9.29 1986, 125.6, .3110, 547.8, 547.8, 9.02 1987, 183.8, .5368, 565.0, 565.0, 8.63 1988, 118.6, .3509, 495.2, 495.2, 8.54 1989, 149.4, .5121, 435.3, 435.3, 9.18 1990, 132.5, .5359, 632.1, 632.1, 9.79 1991, 147.1, .4091, 617.2, 617.2, 6.24 173 Table 5.16.14 Cantabrian Sea (Functional Vnit 31) : landings (in tannes) by the Spanish fleet, 1982-91 Year Spain Total 1982 ? ? 83 63 63 84 100 100 85 128 128 86 121 121 1981 118 118 88 151 151 89 139 139 90 185 185 91 (-) 108 108 (-) provisional Table 5.16.15 Cantabrian Sea (Functional Vnit 31) : effort (in no. of trips) and CPVE (in kg/(bhp-days)1 100) of trawlers; home port Aviles, 1983-91 • Year Effort CPVE 1983 2 124 3.1 84 2 338 3.9 85 2 201 2.4 86 2 401 3.1 1981 1 869 4.5 88 2 011 5.9 89 1 611 5.3 90 2 013 6.9 91 1 198 3.6 Table 5.16.16 Cantabrian Sea (Functional Vnit 31) : mean si zes (CL in mm) of male and female Nephrops in Spanlsh catches, 1988-91 • Year Males Females 1988 40.3 36.9 89 42.3 39.2 90 42.2 31.9 91 40.9 36.6 174 Table 5.16.17 Nephrops landings (tannes) by Functional Unit plus other rectangles in Management Area (0) - (Vlllc) Year FU25 FU31 Other rectangles Total 1982 431 ? 431 1983 430 63 493 1984 514 100 614 1985 477 128 605 1986 364 127 491 1987 412 118 530 1988 445 151 596 1989 376 139 515 1990 289 185 474 1991 416 108 524 Table 5.16.18 Total Nephrops landings (t) by country in Management • Area (0) - (Vlllc) Year Spain TOTAL 1982 431 431 1983 493 493 1984 614 614 1985 605 605 1986 491 491 1987 530 530 1988 596 596 1989 515 515 1990 474 474 1991 524 524 • 175 Table 5.18.1 West Gallcla (Functlonal Unlt 26) and Gulf of Cadlz (Functlonal Unit 30) : landings (in ton nes) by the Spanish fleet, 1982-91 West Gulf of Year Galicia Cadiz 1982 736 ? 83 786 ? 84 604 ? 85 750 257 86 657 221 1987 671 302 88 640 139 89 626 174 90 401 220 91 (-) 549 NA (- ) provisional Table 5.18.2 West Galicia (Functional Unit 26) : CPUE data (in kg/trip) of Spanish trawlers, • horne ports Muros and Riveira, 1984-91 and Marin 1990-1991 Year Muros Riveira Marin 1984 21.3 20.2 ? 85 33.5 30.7 ? 86 23.9 28.0 ? 87 20.3 25.3 ? 1988 15.4 22.0 ? 89 16.4 27.4 ? 90 14.5 20.6 103.3 91 26.4 29.6 117.5 (-) provisional Table 5.18.3 West Galicia (Functional Unit 26) : mean sizes (CL in mm) of male and female Nephrops in Spa • nish catches, 1982-91 Year Males Females 1982 39.0 38.3 83 35.8 33.1 84 ? ? 85 34.3 31.3 86 36.6 31. 9 1987 ? ? 88 35.0 32.9 89 29.9 28.5 90 26.0 24.8 91 31. 7 30.4 176 .------ Table 5.18.4 N Portugal (Functional Unit 27), : landings (in tannes), by gear, all Portugal 1982-91 Year Trawl Creel Total 82 ?? 14 83 ?? 19 84 ?? 14 85 11 4 15 1986 28 9 37 87 52 19 71 88 55 41 96 89 66 22 88 90 31 17 48 91 40 14 54 (-) provisional Table 5.18.5 N Portugal (Functional Unit 27), : effort and CPUE for Portuguese trawl fishery, 1985-1991 • Year No. Tannes Fishing CPUE Trawlers /Trawler Hours Kg/hr 1985 2 5.3 5362 2.0 1986 3 9.5 6538 4.3 1987 7 7.5 14208 3.7 1988 10 5.5 12251 4.5 1989 7 9.4 9400 7.0 1990 9 3.5 8970 3.5 1991 8 5.0 7499 5.3 Table 5.18.6 N Portugal (Functional Unit 27), : mean sizes (CL in mm) of male and female Nephrops in Portuguese trawl landings and research trawl • surveys, 1985-91 Year Landings Research Surveys Males Females Males Females 1985 40.3 36.6 42.6 39.9 86 40.3 40.9 47.0 39.4 87 No sampling 41. 7 41.2 88 41.3 41.0 39.5 33.0 89 40.8 40.7 ? ? 90 39.6 39.1 42.2 40.0 91 34.4 34.2 38.7 33.2 177 Table 5.18.7 VPA. North Portugal (Functional Unit 27): Males Catch (OOO's) at 'nominal age' . 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 6. O. 28. 39. 30. 23. 2 83. 56. 132. 178. 223. 186. 3 68. 48. 179. 241. 317. 230. 4 33. 30. 115. 156. ln. 168. 5 20. 5. 54. 72. 99. 36. 6 9. 6. 39. 53. 34. 9. 7 14. 3. 28. 37. 23. 1. • Table 5.18.8 VPA. North Portugal (Functional Unit 27): Males Mean weight (kg) at 'nominal age' .1985-1990 Age 1985 1986 1987 1988 1989 1990 1 .0120 .0010 .0120 .0120 .0110 .0130 2 .0230 .0270 .0230 .0230 .0240 .0230 3 .0390 •0380 .0390 .0390 .0400 .0400 4 .0590 .0600 .0580 .0580 .0580 .0590 5 .0810 .0780 .0810 .0810 .0800 .0740 • 6 .0990 .0990 .1010 .1010 .1000 .1010 7 .1530 .1260 .1340 .1320 .1250 .1120 178 Iable 5.18.9 VPA. North Portugal (Functional Unit 27): Males Fishing mortality (F) at 'nominal age'. 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 .0060 .0000 .0159 .0225 .0164 .0032 2 .1516 .0760 .1496 .1330 .1745 .1349 3 .1852 .1237 .3692 .4461 .3688 .2743 4 .1610 .1161 .4843 .6410 .6955 .3394 5 .2291 .0318 .3124 .6445 1.1699 .2860 6 .1917 .0905 .3885 .5nO .7444 .2998 7 .1917 .0905 .3885 .sno .7444 .2998 Iable 5.18.10 VPA. North Portugal (Functional Unit 27): Males • Population numbers (OOO's) at 'nominal age'. 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 1029. 1272. 1953. 1915. 2018. 7913. 2 645. 837. 1042. 1573. 1533. 1625. 3 443. 454. 635. 734. 1128. 1054. 4 243. 301. 328. 360. 385. 639. 5 109. 169. 220. 166. 155. 157. 6 55. 71. 134. 132. 71. 39. 7 86. 38. 97. 93. 48. 5. Iable 5.18.11 VPA. North Portugal (Functional Unit 27): Males Yield (tonnes),Fbar,Iotal stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1985-1990 Year, Yield, Fbar, TSB, SSB, log R 2- 6 1985, 11.2, .1837, 86.3, 86.3, 6.94 1986, 6.4, .0876, 84.3, 84.3, 7.15 1987, 29.2, .3408, 135.5, 135.5, 7.58 1988, 39.1, .4883, 147.6, 147.6, 7.56 1989, 42.8, .6306, 151.9, 151.9, 7.61 1990, 27.4, .2669, 236.2, 236.2, 8.98 179 Table 5.18.12 VPA. North Portugal (Functional Unit 27): Females Catch (000'5) at 'nominal age' . 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 5. 5. 58. 78. 35. 15. 2 11. 28. 58. 78. 47. 30. 3 20. 50. 52. 71. 85. 54. 4 16. 92. 53. 71. 92. 69. 5 15. 125. 69. 93. 76. 50. 6 9. 39. 75. 101- 81. 45. 7 9. 50. 67. 91. 83. 58. 8 7. 50. 62. 83. 82. 56. 9 3. 27. 60. 81. 81. 45. 10 9. 186. 308. 413. 320. 100. • Table 5.18.13 VPA. North Portugal (Functional Unit 27): Females Mean weight (kg) at 'nominal age' .1985-1990 Age 1985 1986 1987 1988 1989 1990 1 .0130 .0150 .0130 .0120 .0110 .0140 2 .0180 .0180 .0170 .0170 •0180 .0180 3 .0220 .0220 .0210 .0210 .0220 .0220 4 .0260 .0260 .0260 .0260 .0260 .0260 • 5 .0310 .0310 .0310 .0310 .0310 .0310 6 .0350 .0330 .0360 .0360 .0360 .0360 7 .0420 .0420 .0410 .0410 .0410 .0420 8 .0440 .0450 .0460 .0460 .0460 .0460 9 .0500 .0500 .0510 .0510 .0510 .0500 10 .0820 .0860 .0790 .0790 .0720 .0650 180 Table 5.18.14 VPA. North Portugal (Functional Unit 27): Females Fishing mortality (F) at 'nominal age'. 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 .0003 .0004 .0032 .0048 .0029 .0014 2 .0008 .0022 .0056 .0050 .0034 .0028 3 .0016 .0038 .0047 .0076 .0061 .0043 4 .0016 .0082 .0044 .0071 .0110 .0055 5 .0016 .0145 .0069 .0086 .0084 .0066 6 .0011 .0045 .0098 .0112 .0084 .0056 7 .0014 .0073 .0086 .0132 .0103 .0067 8 .0019 .0086 .0100 .0119 .0134 .0078 9 .0018 .0083 .0115 .0147 .0130 .0081 10 .0018 .0083 .0115 .0147 .0130 .0081 Table 5.18.15 VPA. North Portugal (Functional Unit 27): Females Population numbers (OOO's) at 'nominal age'. 1985-1990 Age 1985 1986 1987 1988 1989 1990 1 15990. 13370. 20030. 17948. 13511. 11469. 2 15492. 13087. 10942. 16346. 14624. 11030. 3 13029. 14007. 11816. 9845. 14716. 13187. 4 10074. 11770. 12626. 10641. 8841. 13235. 5 10093. 9100. 10562. 11374. 9561. 7913. 6 8001. 9118. 8115. 9492. 10204. 8579. 7 6788. 7231. 8213. 7272. 8493. 9156. 8 3811. 6134. 6495. 7368. 6494. 7606. 9 1649. 3442. 5502. 5819. 6588. 5798. 10 5243. 23597. 28293. 29734. 26091. 13051. Table 5.18.16 VPA. North Portugal (Functional Unit 27): Females Yield {tonnes),Fbar,Total stock biomass (tannes). spawning stock biomass (tannes). Ln recruitment 1985-1990 Year, Yield, Fbar, 1SB, SSB, Log R 3- 8 1985, 3.4, .0015, 2593.4, 2385.5, 9.68 1986, 30.9, .0078, 4414.5, 4213.9, 9.50 1987, 42.0, .0074, 4793.7, 4533.3, 9.90 1988, 56.4, .0099, 4953.8, 4738.5, 9.80 1989, 45.1, .0096, 4490.6, 4342.0, 9.51 1990, 20.7, .0061, 3420.1, 3259.5, 9.35 181 Table 5.18.11 SW Portugal (Functional Unit 28), and S Portu- gal (Functional Unit 29) landings (in tonnes) by country and gear, 1982-91 Year Portugal Spain Total Trawl Creel Total Trawl 1982 90 0 90 1 301 1 391 83 251 0 251 0 251 84 458 0 458 0 458 85 509 0 509 0 509 86 465 0 465 0 465 1981 498 11 509 0 509 88 405 15 420 0 420 89 463 6 469 0 469 90 363 4 361 0 361 91 413 5 418 0 418 Table 5.18.18 SW Portugal (Functional Unit 28), and S Portu- gal (Functional Unit 29) effort expressed as • landing days and LPUE as kg / landing day 1982-91 and effort as hours and epUE as kg/hr Year Number Tonnes/ Number of epUE Trawlers Trawler Fishing hours kg/hr 1982 14 6.5 30185 2.9 83 30 8.6 14551 3.5 84 31 12.4 91581 5.0 85 39 13.0 104553 4.9 86 41 11. 3 89358 5.2 1981 41 12.1 83220 6.0 88 38 10.1 61321 6.6 89 34 13.6 52032 8.9 90 31 9.8 58584 6.2 91 39 12.1 63962 1.4 Table 5.18.19 SW Portugal (Functional Unit 28), and S Portu gal (Functional Unit 29) :mean sizes (CL in mm) of male and female Nephrops in Portuguese trawl landings and research trawl surveys, 1983-91 Year Landings Research Surveys Males Females Males Females 1983 36 32 36 32 84 33.5 30.4 36 32 85 37.3 34.2 36 30 86 36.6 32.1 36 32 1981 34.0 31. 9 34 31 88 35.1 32.5 37.3 34.4 89 31.4 33.5 33.6 29.9 90 31.5 33.6 34.1 39.4 91 36.6 31. 9 31.5 31.1 182 Table 5.18.20 VPA. SW and South Portugal (Functional Unit 28&29) : Males Catch (000' s) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 1779. 539. 1135. 1360. 767. 1126. 247. 808. 2 5461. 3189. 2431. 5234. 3513. 2213. 2495. 3779. 3 1449. 2387. 2566. 1716. 2323. 2007. 1930. 2326. 4 843. 977. 1435. 916. 558. 1886. 1306. 1740. 5 371. 548. 442. 309. 279. 617. 397. 599. 6 202. 334. 197. 135. 174. 224. 92. 164. 7 131. 151. 106. 185. 88. 79. 49. 102. 8 87. 44. 25. 67. 44. 36. 20. 29. 9 27. 15. 17. 26. 14. 19. 4. 2. 10 14. 10. 12. 18. 19. 16. O. 4• • Table 5.18.21 .VPA. SW and South Portugal (Functional Unit 28&29) : Males Mean weight (kg) at 'nominal age'.1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0110 .0100 .0090 .0100 .0100 .0090 .0100 .0090 2 .0170 .0200 .0200 .0170 .0190 .0190 .0200 .0190 3 .0350 .0350 .0340 .0350 .0330 .0350 .0350 .0350 4 .0540 .0530 .0550 .0540 .0530 .0550 .0540 .0540 5 .0740 .0770 .0740 .0740 .0770 .0740 .0740 .0720 6 .0970 .0960 .0970 .1000 .0960 .0950 .0950 .0960 7 .1170 .1150 .1140 .1160 .1160 .1160 .1170 .1170 8 .1350 .1330 .1340 .1330 .1340 .1340 .1330 .1280 9 .1460 .1490 .1520 .1500 .1470 .1510 .1440 .1410 10 .1710 .1700 .1660 .1820 .1860 .1790 .1570 .1740 183 Table 5.18.22 VPA. SW and South Portugal (Functional Unit 28&29): Males Fishing mortality (F) at 'nominal age'. 1984-1991 1990 1991 Age 1984 1985 1986 1987 1988 1989 1 .1513 .0602 .0727 .1028 .0600 .0885 .0163 .0612 2 .6256 .4399 .4148 .5474 .4154 .2450 .2871 .3627 3 .4720 .6241 .7769 .5837 .5029 .4449 .3498 .4739 4 .4560 .6834 1.0007 .7193 .3797 1.0295 .5876 .6147 5 .4094 .6110 .7804 .6066 .4993 .9618 .6261 .5946 6 .5206 .8044 .4624 .5818 .8477 .9957 .3523 .5814 7 .7390 .9598 .6498 1.1030 .9793 1.3390 .6082 .8382 8 1.2763 .6031 .4019 1.2194 .8728 1.7088 1.8551 .9515 9 .8453 .7891 .5047 .9681 .8999 1.3479 .9385 .7903 10 .8453 .7891 .5047 .9681 .8999 1.3479 .9385 .7903 Table 5.18.23 VPA. SW and South Portugal (Functional Unit 28&29): Males Population numbers (OOO's) at ' nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 13943. 10175. 17833. 15331. 14518. 14650. 16914. 14994. 2 12822. 9813. 7844. 13576. 11326. 11194. 10978. 13624. 3 4214. 5615. 5175. 4241. 6430. 6121. 7173. 6745. 4 2521. 2152. 2463. 1948. 1937. 3183. 3212. 4139. 5 1210. 1308. 890. 741. 777. 1085. 931. 1461. 6 545. 658. 581. 334. 331. 386. 339. 407. 7 273. 265. 241. 300. 153. 116. 117. 195. 8 130. 107. 83. 103. 81. 47. 25. 52. 9 52. 30. 48. 46. 25. 28. 7. 3. 10 27. 19. 33. 31. 35. 23. 1. 8. Table 5.18.24 VPA. SW and South Portugal (Functional Unit 28&29): Males Yield (tonnesJ,Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1991 Year, Yield, Fbar, TSB, SSB, Log R 3- 8 1984, 289.1, .6456, 859.1, 859.1, 9.54 1985, 305.7, .7143, 824.8, 824.8, 9.23 1986, 296.8, .6787, 802.3, 802.3, 9.79 1987, 285.9, .8023, 786.9, 786.9, 9.64 1988, 240.4, .6803, 805.6, 805.6, 9.58 1989, 312.8, 1.0800, 878.9, 878.9, 9.59 1990, 237.5, .7299, 932.4, 932.4, 9.74 1991, 330.0, .6757, 1029.1, 1029.1, 9.62 184 Table 5.18.25 VPA. SW and South Portugal (Functional Unit 28&29) : Females Catch (OOO's) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 2463. 691. 1232. 2113. 1178. 1301. 339. 990. y/ 2 2531. 855. 843. 2352. 1246. 741. 538. 1392. 3 1400. 1031- 840. 1436. 1263. 877. 910. 1326. 4 1059. 1208. 1760. 1195. 1432. 667. 890. 1132. 5 583. 1399. 890. 959. 1276. 767. 860. 888. 6 488. 1075. 484. 584. 580. 525. 448. 292. 7 277. 699. 455. 476. 652. 367. 287. 168. 8 144. 430. 88. 181. 95. 255. 169. 168. 9 51- 171- 205. 106. 65. 185. 136. 119. 10 91. 153. 311. 499. 103. 425. 278. 177. • Table 5.18.26 VPA. SW and South Portugal (Functional Unit 28&29) : Females Mean weight (kg) at 'nominal age' .1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .0110 .0110 .0100 .0110 .0110 .0100 .0110 .0110 2 .0150 .0140 .0150 .0150 .0140 .0140 .0150 .0150 3 .0190 .0190 .0190 .0190 .0190 .0190 .0190 .0190 4 .0230 .0230 .0230 .0230 .0230 .0230 .0230 .0230 5 .0280 .0270 .0270 .0270 .0270 .0270 .0270 .0270 6 .0320 .0320 .0320 .0320 .0320 .0320 .0320 .0320 7 .0370 .0370 .0370 .0370 .0370 .0370 .0370 .0370 8 .0430 .0430 .0430 .0430 .0430 .0430 .0430 .0430 9 .0460 .0460 .0490 .0470 .0480 .0480 .0480 .0480 10 .0610 .0580 .0570 .0680 .0640 .0640 .0580 .0620 185 Females Table 5.18.27 VPA. SW and South Portugal (Functional Unit 28&29): Fishing mortality (F) at 'nominal age'. 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 .2536 .0859 .1403 .2360 .1367 .1259 .0289 .1102 2 .3053 .1244 .1362 .4068 .2021 .1136 .0668 .1507 3 .2349 .1754 .1553 .3206 .3538 .1914 .1782 .2083 4 .2480 .2909 .4477 .3062 .5377 .2848 .2697 .3115 5 .2283 .5273 .3215 .4156 .5475 .5467 .6322 .4172 6 .3286 .7350 .3091 .3216 .4221 .4030 .6339 .4025 7 .2081 .9485 .7078 .5001 .6285 .4571 .3571 .4575 8 .3332 .5034 .2504 .6041 .1555 .4767 .3498 .3253 9 .2897 .7284 .4221 .4748 .4017 .4452 .4465 .3947 10 .2897 .7284 .4221 .4748 .4017 .4452 .4465 .3947 Table 5.18.28 VPA. SW and South Portugal (Functional Unit 28&29): Females Population numbers (OOO's) at ' nominal age' . 1984-1991 Age 1984 1985 1986 1987 1988 1989 1990 1991 1 12080. 9249. 10356. 11046. 10146. 12109. 13129. 10449. 2 10085. 7675. 6949. 7369. 7142. 7245. 8741. 10443. 3 7011. 6724. 6132. 5487. 4439. 5280. 5852. 7398. 4 5058. 5016. 5106. 4751. 3603. 2820. 3945. 4431. 5 2996. 3572. 3393. 2953. 3165. 1904. 1919. 2726. 6 1827. 2158. 1907. 2226. 1763. 1656. 997. 923. 7 1547. 1190. 936. 1267. 1460. 1046. 1002. 479. 8 534. 1137. 417. 417. 695. 705. 599. 634. 9 214. 346. 622. 294. 206. 539. 396. 382. 10 380. 309. 945. 1383. 325. 1238. 807. 567. Table 5.18.29 VPA. SW and South Portugal (Functional Unit 28&29): Females Yield (tonnes),Fbar,Total stock biomass (tonnes), spawning stock biomass (tonnes), Ln recruitment 1984-1991 Year, Yietd, Fbar, 1SB, SSB, Log R 3- 8 1984, 172.3, .2635, 789.3, 656.4, 9.40 1985, 200.2, .5301, 744.6, 642.9, 9.13 1986, 169.3, .3653, 731.3, 627.7, 9.25 1987, 222.2, .4114, 769.2, 647.7, 9.31 1988, 178.2, .4409, 635.3, 523.7, 9.22 1989, 153.5, .3933, 666.2, 545.1, 9.40 1990, 127.6, .4035, 689.8, 545.4, 9.48 1991, 146.4, .3537, 715.7, 600.7, 9.25 Table 5.18.30 Nephrops landings (tonnes) by Functional Unit plus other rectangles in Management Area (Q) - (IXa) Year FU26 FU27 FU28+29 FU30 Other rectangles Total 1982 736 14 1397 ? 2147 1983 786 19 257 ? 1062 1984 604 14 458 ? 1076 1985 750 15 509 257 1531 1986 657 37 465 221 1380 1987 671 71 509 302 1553 1988 640 96 420 139 1295 1989 626 88 469 174 1357 1990 401 48 367 220 1036 1991 549 54 479 NA 1082 Table 5.18.31 Total Nephrops landlngs (t) by country in Management Area (Q) - (IXa) Year Portugal Spain TOTAL 1982 104 2043 2147 1983 276 786 1062 1984 472 604 1076 1985 524 1007 1531 1986 502 878 1380 1987 580 973 1553 1988 516 779 1295 1989 557 800 1357 1990 415 621 1036 1991 533 549 1082 --Landings for FU 30 not available far 1991 187 labte 6.1 Northern Ireland Effort and CPUE/lPUE for the period 1981-90 ------.------Year Catches landings Mean Hours CPUE lPUE CPUE lPUE tonnes tonnes HP Fishing t/hp*hrs t/hp*hrs kg/hr kg/hr X1000 X1000 ------.------_.------.------.-.-----._-.------1981 5850 3752 246 140973 .169 .108 41.5 26.6 1982 6727 4482 260 140824 .184 .122 47.8 31.8 1983 6410 4949 1984 5191 4027 240 141856 .152 .118 36.6 28.4 1985 5409 4310 236 154473 .148 .118 35.2 27.9 1986 6282 5197 242 152407 .170 .141 41.2 34.1 1987 5739 4990 246 171036 .136 .119 33.6 29.2 1988 5669 5220 246 168202 .137 .126 33.7 31.0 1989 6232 5517 269 196951 .118 .104 31.6 28 1990 5691 5505 272 195765 .107 .103 29.1 28.1 ------.----_._. __ ._------.------_._.------.---- Table 6.2 Relative number and description of six different types of Nephrops trawl and ground gear currently in use in the North Minch (Based on 1990 fleet survey of 87 boats). Gear Type Description number 1.Grassrope Manilla rope with lead weights 2 2.Rubber disc wire threaded through small 32 rubber discs 3. Bobbins Large steel bobbins on wire 4 4. Rockhopper Large rubber discs mounted 42 below footrope 5.Twin trawl Two nets joined and towed by 11 one boat usually with rubber disc ground gear 6.Twin rockhopper Two nets with rockhopper gear 1 Total 92 [Types 1,2 & 5 used on "clean" ground; 3,4 & 6 used on "hard" ground] 188 Table 6.3 Mean LPUE (Kg./Hr.) for five main types of fishing gear used by North Minch vessels surveyed. Data extracted from official statistics in square 45E4 only. Figures in brackets are the number of vessels in each sampie (From Bundy,1990). Gear Type Year Quarter 2 3 4 5 6 1989 1 19.7(11) 16.9(4) 15.8(8) 22.5(2) 2 42.1(14) 52.1(4) 41. 3(12) 73.1(3) 109.5(1 ) 3 30.9(15) 27.4(4) 25.2(16) 34.1(2) 54.0(1 ) 4 24.8(4) 22.8(2) 23.0(7) 33.80 ) 47.0(1) 1988 1 21.5(9) 22.8(5) 20.3(11) 25.6(1 ) 2 32.8(15) 29.6(5) 30.0(11) 71.3(3) 3 43.2(16) 37.2(5) 37.7(13) 72.70 ) 4 24.8(13) 24.1(4) 22.4(9) 25.60 ) 1987 3 38.4(15) 30.8(9) 27.9(9) 49.0(1) 1986 2 31.1(13) 39.0(9) 38.50) 44.0(1) All Quarters 30.9 30.3 28.2 45.2 70.2 Gear types (see Table 6.2): 2 - Rubber disc; 3 - Bobbins; 4 - Rockhopper; 5 - Twin rig; 6 - Twin rig with rockhoppers Table 6.4 Landings, effort and LPUE of Scottish single and multi-rig nets on different grounds 1991. Prop. = proportion of total effort attributable to multiple-rigged gear. Single net Multi net Ground(FU) mt. hours LPUE rot. hours LPUE prop. (X) Farn Deeps(6) 139 9.7 14.3 10 0.3 29.8 3.3 Fladen(7) 409 11. 4 35.8 2615 67.1 39.0 85.5 F.Forth(8) 1231 63.9 19.3 128 5.5 23.2 7.9 Moray F. (9) 571 25.1 22.7 713 22.0 32.5 46.7 Noup(10) 23 0.9 25.3 87 3.9 22.6 81.2 N.Minch(ll) 2116 90.2 23.5 105 2.9 36.7 3.1 S.Minch(12) 3000 130.7 23.0 466 15.0 31.0 10.3 Clyde(13) 1780 120.1 14.8 1057 44.9 23.6 27.2 E.lrish(14) 10 0.5 19.8 10 0.4 26.4 42.9 W.lrish(15) 11 0.5 21. 4 10 0.5 19.2 50.4 Totals(6-15) 9290 453.0 20.5 5201 162.5 32.0 26.4 Totals(7-13) 9130 442.3 20.6 5171 161. 3 32.1 26.7 189 .----~- -- -- Table 7.1 Proposal for suitable grouping of Pandalus and Nephrops stocks within the new Area Based Groups. For each stock an indication is given of whether the stock is multi-fleet or not. The numbers of people involved in the assessments are also given. Area Group Stocks to be lncluded Single(S)/Multi(M) Number of people Pandalus lIla &. Norw.Dps. M Pandalus Fladen Ground M 5 Pandalus Farn Deeps S Kattegat, Nephrops FU 3&4 M Skagerrak Nephrops FU 5 M and Nephrops FU6 S North sea Nephrops FU 7 M 7 Nephrops FU 8 S Nephrops FU9 S Nephrops FU 10 Not assessed Nephrops FU 11 M Nephrops FU 12 M Northern Nephrops FU 13 S 4 Shelf Nephrops FU 14 S Nephrops FU 15 M Nephrops FU 16 M Nephrops FU 17 M Nephrops FU 18 Not assessed Nephrops FU 19 11 Nephrops FU 20-22 M Southern Nephrops FU 23&24 S 5 Shelf Nephrops FU 25 S Nephrops FU 26 S Nephrops FU 27 S Nephrops FU 28&29 S Nephrops FU 30 Not assessed Nephrops FU 31 S 190