Orkney Sustainable Fisheries Ltd. No.21

Orkney Shellfish Research Project Logbook and Observer Report 2013 - 2016

Matthew T. Coleman & Elisabete Rodrigues 18.05.2017

Coleman M T., Rodrigues E., (2017). Logbook and Observer Report: Orkney Shellfish Research Project. Orkney Sustainable Fisheries Ltd. No. 21, Pp 25.

Executive summary This report outlines the results of the logbook and observer programme undertaken as a component of the Orkney Shellfish Research Project (OSRP) from 2013 – 2016. The logbook programme involved the participation of Orkney creel fishers in submitting daily landing records relating to the number of creels hauled per day and the amount in kilograms of each commercial species retained. Additional information relating to undersize interaction and non-target species was also recorded. The OSRP observer programme was undertaken by Orkney Sustainable Fisheries marine scientists. This involved accompanying fishers on commercial fishing trip ranging from 1 – 2 days. During these trips detailed information was recorded relating to catch composition, size frequency of undersize individuals and detailed non-target species recording.

Logbook programme

A total of 8 vessels participated within the OSRP voluntary logbook programme, submitting daily effort and landings information from 2013 -2016. These vessels represented 8% of registered fishing vessels within Orkney.

Reported catch composition was dominated by brown which accounted for 80% of total landings reported within the creel fishery. Over the same time period velvet crab accounted for 15%, European lobster 4% and green 1%. Catch-composition was seen to fluctuate temporally with fisheries occurring within seasonal time frames. Landing per unit effort (LPUE) per100 creel estimates were derived from submitted logbook information. Brown crab LPUE/100 creels ranged from 15.8 - 218 kg/100 creels with peaks documented in Q3 and Q4. In the case of velvet crab LPUE/100 creels ranged from 3.7 – 34.7kg, with peaks documented in Q1 and Q4 identifying it as a winter fishery. European lobster LPUE was highly seasonal with peaks in Q3 annually, LPUE/100 creels ranged from 0.7 – 9.5kg.

Undersize interaction was recorded within the logbook scheme as an arbitrary estimated percentage of total catch. Brown crab dominated undersize interaction responsible for 48% of total reported discards within the creel fishery. Seasonal trends in discarding were observed with the high brown crab discards recorded in Q1 and Q2 coinciding with winter inshore fisheries of which it is not a major part. Velvet crab accounted for 14% of total reported discards with species specific discard peaks occurring within Q1 and Q2. European lobster accounted for 4% of total discards. Discards peaked within Q3 only coinciding with the short annual fishery.

Information relating to non-target species was sporadic with varying levels recorded over the course of the OSRP. A total of 14 species were recorded; 10 demersal fish species, 1 congridae and 2 . Of those species recorded displayed high levels of by-catch throughout the OSRP, with Common Dogfish the second highest and peak annual interactions documented within August.

Observer programme

121 trips were conducted by OSF marine scientists over the course of the OSRP on board 16 different commercial vessels. Overall boat participation and observe trip numbers increased each year.

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Observed total catch composition (both landed and sub-legal individuals) was dominated by brown crab which accounted for 74% of total observed catch composition, with velvet crab responsible for 21%, European lobster 3% and Green crab 2%.

Retained catch composition was observed to be dominated by brown crab, accounting for 59% of total landings, whilst velvet crab was responsible for 33% and European lobster 3%. Observed brown crab LPUE remained stable throughout the observer programme. Seasonal patterns in European lobster LPUE was observed, mirroring that of the logbook programme, with observed peak within July – September. In the case of velvet crab observed peaks in LPUE occurred in late Oct – Dec coinciding with the winter fishery.

Observed undersize interaction was seen to vary according to species. In the case of brown crab 67% of all brown crab observed was discarded. Discard levels fluctuated with peaks observed within Q1 and Q4. Discarded brown crab ranged from 53 – 212mm carapace width (CW) with the average discarded male being 108.2 mm and female being 109 mm CW. 48% of velvet crab was discarded, with discard peaks observed within October and November. Discarded individuals ranged from 50 – 90 mm CW, whilst the average sizes of discarded males was 64.54 mm and 63.8 mm females. 45% of European lobsters were discarded, with discard peaks occurring within August and September. Discarded individuals ranged from 55 – 140mm carapace length (CL), the average sizes of discarded males was 76.6mm and 86.2mm CL for females.

A total of 42 different non-target species were recorded within the observer programme. Of those recorded Common Dogfish was recorded as having peak annual interactions within August. Atlantic Cod was also recorded as interacting within the fishery at low constant levels throughout the year. Of those species recorded within the voluntary logbook programme all were observed by marine scientists during observer trips.

Overall the logbook and observer programme provided valuable spatial and temporal information relating to fishing activities, with the observer programme validating fisheries dependant data provided within the logbook scheme and providing detailed creel by creel information. The OSRP observer programme has provided valuable insight into the levels and types of species that interact within the creel fishery and is of significant benefit in the progression toward sustainable management of the fishery.

Recommendations surrounding both projects include increasing fishers’ participation within the logbook and observer programme, providing better spatial coverage across vessels sizes and further information relating to stock health. Secondly OSF will implement a detailed non-target species sampling protocol, providing further information relating to the size composition of non-target species.

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Contents Project Background ...... 1

1. Logbook Report ...... 3

1.1 Catch Composition and Logbook Landing per Unit Effort...... 3

1.2 Undersize and Discard Catch Composition ...... 6

1.3. Non- Target Species ...... 9

1.4 Summary ...... 11

2. Observer Report ...... 12

2.1 Overview ...... 12

2.2 Cath per Unit effort ...... 14

2.3 Landing Per Unit Effort ...... 16

2.4 Discard Per Unit Effort ...... 18

2.5 Non- target Species...... 20

2.6 Summary ...... 22

3. Conclusion ...... 22

References: ...... 23

Appendix ...... 1

List of Tables Table 1 Vessel participation within OSRP logbook scheme and summary statistics of creel deployment per year (2013- 2016) ...... 3 Table 2 Reported landings and catch composition per year reported within logbook scheme (2013-2016) 3 Table 3 Average monthly brown crab landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016) ...... 4

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Table 4. Average Monthly velvet crab landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016) ...... 5 Table 5. Average monthly European lobster landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016) ...... 5 Table 6.Monthly variation in green crab landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016) ...... 6 Table 7. Total number Atlantic Cod (Gadus morhua) reported in the logbooks by year (2013-2016) ...... 10 Table 8. Total number of Common Dogfish (Scyliorhinus caniculus) reported in logbooks by year (2013- 2016) ...... 10 Table 9 Total observer coverage achieved within the OSRP and coverage associated within each ICES rectangle ...... 14 Table 10 Monthly changes in brown crab catch per 100 creels (Jan – Dec 2016) ...... 14 Table 11 Monthly changes in European lobster catch per 100 creels (Jan – Dec 2016)...... 15 Table 12 Monthly changes in velvet crab catch oer 100 creels (Jan – Dec 2016) ...... 15 Table 13 Monthly changes in green crab catch per 100 creels (Jan – Dec 2016) ...... 16 Table 14 Monthly changes in brown crab landing per 100 creels (Jan – Dec 2016) ...... 16 Table 15 Monthly changes in European lobster landing per 100 creels (Jan – Dec 2016) ...... 17 Table 16 Monthly changes in velvet crab landing per 100 creels (Jan – Dec 2016) ...... 17 Table 17 Monthly changes in green crab landing per 100 creels (Jan – Dec 2016) ...... 17 Table 18 Monthly brown crab discards per 100 creels (Jan – Dec 2016) ...... 18 Table 19 Monthly European lobster discards per 100 creels (Jan – Dec 2016) ...... 19 Table 20 Monthly velvet crab discards per 100 creels (Jan – Dec 2016) ...... 19 Table 21. Monthly green crab discards per 100 creels (Jan – Dec 2016) ...... 20

Appendix Appendix 1 Log transformed landing per unit effort per 100 creels reported within the logbook scheme (2013 - 2016)...... 1 Appendix 2 Monthly total catch compositions per commercial important species reported by the logbook fleet by year (2013 – 2016) ...... 2 Appendix 3 Monthly percentage undersize interaction rates of commercially important crustacean species reported by the logbook fleet (2012 – 2016) ...... 3 Appendix 4 Monthly discard rates of commercially important crustacean species (Jan – Dec 2016) ...... 4 Appendix 5 Total recorded interaction of non-target species reported by the logbook fleet (2014 -2016) .. 5 Appendix 6 Total number of non-target species recorded during observer trips (2014 -2016) ...... 6

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Appendix 7 Average LPUE of commercial species recorded by Observers (2014 -2016) ...... 8 Appendix 8 Average LPUE per year for Atlantic Cod, Common Dogfish and V-notch lobsters recorded by the observer programme (2014 -2016) ...... 8 Appendix 9 Catch frequency of brown crab below minimum landing size (140mm carapace width) and discarded during observer trips (2015 -2016) ...... 9 Appendix 10 Catch frequency of velvet crabs below minimum landing size (2015 – 65mm CW; 2016 – 70mm CW) and discarded during observer trips (2015 – 2016) ...... 10 Appendix 11 Catch frequency of European lobster below minimum landing size and discarded during observer trips (2016) ...... 11 Appendix 12 Catch frequency of green crabs below minimum landing size and discarder during observer trips (2016) ...... 12

Glossary:

LPUE: Landing per unit effort (LPUE) refers to all species of commercial importance that are above MLS and retained for profit. In this case LPUE refers to kilograms (Kg) landed per 100 creels.

CPUE: Catch per Unit Effort (CPUE) refers to total fishing interaction of commercial targeted species by the creel fishery. This encompasses individuals both above and below minimum landing size, recently moulted or individuals discarded due to unmarketability (black spot, missing limbs, etc.). In this case CPUE refers to the number of individuals caught per creel 100 creels.

DPUE: Discard per unit effort (DPUE) refers to all commercial species that are below minimum landing size and are restricted by additional regulatory measures and subsequently returned. Individuals that are restricted by regulatory measures include, V-notch lobster; “White crab”, berried brown crab and berried velvet crabs. LPUE in these cases refers to the number of individuals discarded per creel 100 creels.

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Orkney Shellfish Research Project

Logbook and Observer Report

2013 -2016

Project Background The Orkney shellfish research project (OSRP) has come to end of its four- year project (2013 – 2016). The project encompasses a number of objectives that addressed the needs of two important sectors: Inshore fisheries and marine renewables.

Specific objectives of the project relating to the fishing sector were:

• To assess the status of Orkney crustacean stocks in relation to sustainability criteria;

• To provide monitoring data and biological understanding to support the development and implementation of a harvest strategy and management systems for sustainable fishing in the context of marine spatial planning for renewable energy and other activities in Pentland Firth and Orkney waters;

• To satisfy shellfish consumers of Orkney’s commitment to sustainable fishing.

Objectives relating to the marine renewable energy industry:

• To determine key areas providing value to the Orkney creel fishery in terms of catch rates and the magnitude, composition and quality of catches.

• To describe spatial patterns of space use by the Orkney creel fishery in terms of fishing effort, navigation, relocation of gear during bad weather and seasonal and inter-annual patterns of variability.

• To determine locations of critical habitat for crustacean species targeted by the Orkney creel fishery, particularly in terms of spawning areas and movement and migration patterns of brown crab.

This report outlines the results collected over the past 4 years specifically relating to the logbook scheme and observe programme. These two programmes have provided a data set can now be used to monitor the fishery, collecting important information on the spatial and temporal changes in fishing activity over time. Additionally, the role of the OSRP observer programme has allowed the comparison and validation of the use of fishery dependant data collected via the logbook scheme and its role in monitoring the fishery.

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This report is broken into 2 main components:

1. Logbook Programme 2. Observer Programme

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1. Logbook Report A total of 8 vessels participated within the OSPR logbook scheme from 2013 -2016, representing 7% of the registered inshore Orkney fleet of 107 vessels (Scottish Government, 2015). Over the course of this time-period a total of 256,925 creels were hauled and redeployed by these 8 vessels (Table 1).

The average breakdown of creel deployment was seen to fluctuate between years, however this can be directly related to the number of participating vessels within the logbook programme (Table 1). Additionally, this variability can also be attributed to both the increase in boat size and the number vessels. Large vessels are capable of working larger sets of gear and increasing the overall average variability reported.

Table 1 Vessel participation within OSRP logbook scheme and summary statistics of creel deployment per year (2013- 2016)

Boat Average No. Average No. Creels Year Total No. Creels Participation Creels per Day Per Month 2013 70,129 3 284 ± 40 7,013 ± 3,707 2014 103,270 4 278 ± 23 10,327 ± 5,348 2015 159,410 5 249 ± 19 13,284 ± 4,587 2016 256,925 8 270 ± 53 21,410 ± 14,012 2013 -16 589,734 8 274 ± 110 13,403 ± 9,699

1.1 Catch Composition and Logbook Landing per Unit Effort (LPUE) Total observed landings composition reported by the logbook programme within the OSRP (2013 -2016) demonstrated that brown crab comprised 80% of the total landings, velvet crabs 15%, European lobster

4% and green crabs 1% (Table 2). Table 2 Reported landings and catch composition per year reported within logbook scheme (2013-2016)

Total Catch Composition (%)/Reported Landings (Kg) Total 2013 2014 2015 2016 2013 -2014 Boat Participation 3 4 5 8 9 Brown Crab 40,295 (64) 55,899 (61) 112,726 (72) 351,584 (90.5) 560,504 (80) Velvet Crab 18,719 (30) 30,540 (33 34,675 (22) 23,313 (6) 107,277 (15) European Lobster 3,808 (6) 5,304 (6) 6,314 (4) 10,978 (3) 26,405 (4) Green Crab * * 1,425 (1) 2,264 (0.5) 3,689 (1)

Brown Crab Brown crab was responsible for more than 50% of the landings compositions across all years (Table 2). Within the brown crab fishery seasonal changes in LPUE and catch compositions were observed.

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Increases in LPUE were observed within Q3 with the highest LPUE recorded within this time-period (Appendix 1; Table 3). This can be linked to changes stock behaviour and resulting targeting behaviour of the fishery. Over this time-period large seasonal migration events occur within the brown crab female proportion of the stock (Coleman & Rodrigues, 2015), with females entering the inshore fishery in large numbers to moult and subsequently mate (See Crab tagging Report). The onset of these large migration events are exhibited within the size frequency recorded within market sampling (Rodrigues & Coleman, 2017) with females proportionally dominating catches. In comparison a reverse trend is observed with males dominating catches within Q1 & 2, with skewed size frequencies linked to the limited spatial overlap of the fishery in winter months and the primary habitat distribution of male brown crab, typically occurring within the sublittoral zone of inshore waters.

Table 3 Average quarterly brown crab LPUE (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016)

Q1 Q2 Q3 Q4

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

LPUE (Kg)/100 67.9 53.3 85.4 78.3 42.7 15.8 198.8 123.4 162.4 165.2 157.6 218 Creels £/Kg £1.45 £1.40 £1.40 £1.39 £1.52 £1.49 £1.42 £1.38 £1.40 £1.42 £1.54 £1.60

£ value £98.39 £74.42 £119.63 £108.76 £65.10 £23.54 £282.89 £169.94 £227.27 £234.05 £242.76 £348.15

Velvet Crab Velvet crabs are an important component of the inshore fishery, being the second highest in its overall landings contribution (15%: table 2) within the logbook scheme, but also in terms of value within the inshore fishery as whole (440 tonnes/£1,231 million: Scottish Government, 2015). Total landings contribution fluctuates between years, 2016 for instances were considerably lower (Appendix 2). This in part can be attributed to the types of vessels participating within the logbook scheme in 2016. A number of them primarily targeted brown crab, skewing the observed landings contribution. During this year larger landings of brown crab were also reported than any other year (Appendix 1), indicating increased effort towards targeting this species. In addition the reduced volume of velvet landings in 2016 can be attributed to the changes in MLS, with an increase of 65mm to 70mm March 2016. This change in MLS is exhibited in monthly landings compositions with velvets responsible for 50% in Nov/Dec 2015, and 25% in Jan/Feb 2016, after which their contribution drops dramatically to <5% in later months. It is important however to interpret changes in LPUE and catch compositions within a temporal context. Changes in velvet catch compositions will fluctuate due to the targeting behaviour of the fishery, with

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decreases in landings recorded post Q1 for a large proportion of vessels due to the changes in primary target species, in this case being brown crab and subsequently lobster in Q3 (Table 4; Appendix 2).

Table 4. Average quarterly velvet crab landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016)

Q1 Q2 Q3 Q4 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec LPUE (Kg)/100 27.2 26.8 11.2 8.4 18.6 6.9 3.7 9.1 16 10.5 32.9 34.7 Creels £/Kg £2.79 £3.23 £3.43 £3.76 £3.74 £3.26 £2.95 £2.72 £2.27 £2.16 £2.21 £4.06 £ value £76.00 £86.62 £38.46 £31.60 £69.57 £22.48 £10.90 £24.72 £36.31 £22.68 £72.85 £140.78

European Lobster The Orkney European lobster fishery is heavily influenced by environmental conditions, specifically sea bottom temperature (Lizárraga et al, 2015), resulting in a highly seasonal fishery. This seasonality is mirrored within the annual catch composition and LPUE data collected by the logbook index fleet over the course of the OSRP. Peaks in lobster landings and catches were typically seen in Q3, with gradual increases observed pre Q3 and subsequent declines in Q4 (Table 5; Appendix1 & 2). This rise and fall in catches are seen to follow seasonal and yearly changes in sea bottom temperature and sea- surface records (Appendix 1), reaffirming the significant relationship highlighted between this species (Lizárraga et al, 2015) that doesn’t seem to occur within any other crustacean species within the inshore creel fishery. Additional factors influencing catch compositions and the decline in lobster LPUE catch compositions can be related to the seasonal movements of the fishery, with fishers excluded from ideal fishing grounds in later months due to adverse winter weather. In comparison to previous years, little to no difference was seen between overall yearly catch compositions (Appendix 1), this change being surprising due to the introduction of increases MLS of 87 – 88mm (Scottish Government, 2016). However, the subsequent increase to 90mm could result in a more detectable change in lobster landings in subsequent years.

Table 5. Average quarterly European lobster landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016)

Q1 Q2 Q3 Q4 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec LPUE (Kg)/100 1.7 1.8 2.7 1 2.8 1.6 3.2 9.5 6.7 6.3 3.3 0.7 Creels £/Kg £17.4 £18.8 £15.77 £12.71 £11.81 £9.25 £9.94 £10.08 £11.50 £13.30 £17.16 £21.86 £ value £29.6 £33.8 £42.58 £12.71 £33.06 £14.80 £31.81 £95.75 £77.05 £83.77 £56.62 £15.30

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Green Crab Green crab represents the least commercially valuable species, undergoing highly seasonal levels of exploitation. However even though this species has little commercial value, its makes up an important component of the winter fishery and is the mainstay for a number of smaller inshore vessels that operate as part of the Orkney fleet. The seasonal nature of the fishery is not clearly highlighted in 2016, with peaks in LPUE occurring in both Q3 and Q4 and previous years (Table 6; Appendix 2). The low economic value of this species is exemplified when comparing its 1st value sale against velvet crabs. In the case of November 2016, similar weights of both species are landed, however the market value of the velvets at the same weight is 225% greater. The low commercial value of this species results in the fishery operating under a high-volume exploitation model. Further research into the green crab fishery is recommended to investigate the implications of this fishery, with OSF building upon research undertaken in 2015 investigating size at maturity of this species within Orkney (Duncan, 2015; Coleman & Rodrigues, 2016).

Table 6. Average quarterly variation in green crab landings (Kg) per 100 creels and associated prices at first sale (Jan – Dec 2016)

Q1 Q2 Q3 Q4 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec LPUE (Kg)/100 - 57.1 75 - 64 69.8 79.4 40 40 83.3 32.5 4 Creels £/Kg £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £00.69 £ value - £33.40 $51.75 - £44.16 £48.16 £54.78 £27.60 £27.60 £57.47 £22.42 £2.76

1.2 Undersize and Discard Catch Composition Discard catch compositions refers to the returning of individuals to the sea which are not retained within the landed catch. Individuals can be discarded for a number of reasons, the most common being that an individual is below the minimum landings size currently enforced for that specific species (lobsters & velvet crabs; Scottish statuary instruments (2016), brown Crab; EC, 1998). In addition, the practise of discarding can also be influenced by a number of other reasons, such as discarding of individuals due to their reduced marketability. This includes larger sizes preferred by merchants, poor condition (missing limbs, black spot, soft individuals) and egg-bearing females. In the case of lobsters, egg bearing females can also be marked with a voluntary v-notch making the individual illegal to land.

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Overall the average percentage discarded per commercially exploited species varied between species throughout the OSRP (Appendix 3&4).

Brown Crab In the case of brown crab the average undersize discard rate reported within the OSRP was 47%, however change in undersize interaction can fluctuate temporally. In the case of Q1 and Q2 an average undersize interaction rate of 48% was reported (Appendix 3), however a large variability in the level of interaction within these two quarters occurs (<95%). This variability can be attributed to the spatial extent of the fishery at this time. Within Q1 and Q2 the extent of the fishery is predominantly restricted within sheltered locations, typically targeting small intertidal species (velvet crab and green crab: Appendix 2). The preferred habitat of both species overlaps with juvenile brown crab nursery areas (Heraghty, 2013) resulting in high undersize interaction rates. Within the tail end of Q2 however declines in undersize interactions is reported. This decline coincides with the movement of the fishery into more exposed offshore areas with differing habitat types which the adult proportion of the stock inhabits. Continued low levels of undersize brown crab interaction is reported from Q2 until the end of Q4 (2016: 26%). The reported peaks within Q3 and Q4 can be linked to subsequent capture of undersize individuals as a by- product of the lobster fishery, with peaks in undersize interaction matching peaks in lobster LPUE (Appendix 1).

For the first time in 2016, slight changes in the logbook scheme enabled differentiation between individuals discarded due to being undersize compared to those unmarketable1 and subsequently discarded (Appendix 4). In 2016 the overall average discarded rate was reported at 27%, with levels of discarding fluctuating within quarters. Within Q1 the average discarding rate was reported as 0.24%. This low level of discarding behaviour can be linked to catches dominated by undersize individuals due to the current spatial extent of the fishery which is mirrored within undersize reporting (See Succorfish Report: Coleman & Rodrigues, 2017). Whilst low levels of discarding are potentially attributed to unmarketable black spot individuals, the level of discarding is seen to increase in later quarters, with peaks in discarding occurring in Q3/4. High levels of discarding within these months can be linked to key biological processes occurring within the fishery, specifically moulting. During these months large volumes of the stock becomes unmarketable with fishermen discarding large individuals greater than MLS due to them being “white2”.

1 Unmarketable in this case can be attributed to individuals that cannot be sold due to damage, black spot infection or moult condition 2 White – White crab refers to an individuals that has recently moulted, causing shell condition to be thin and white in appearance. During this moult stage individuals are not landed due to the limited commercial value.

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Velvet Crab Velvet crab undersize interaction rate averaged 14% within the OSRP. Discards rates were seen to fluctuate throughout the course of the project (39%: 2013; 20%: 2014; 14%: 2015; 5%: 2016).This gradual decline can be attributed to the types of vessel which participated within the logbook programme. In 2016 the participation within the project doubled, however uptake was by those vessels predominantly targeting the brown crab/lobster fishery, compared to those in 2014/2015 with a more equal spread of participants. Though levels of undersize interaction are low overall, indications of a seasonal trend were observed across all years (Appendix 3), with slightly higher levels of undersize interaction reported within Q1 and subsequent increases in Q4. This increase can be linked to changes in the spatial extent of the fishery in Q2/4, with the expansion of the fishery into summer offshore brown crab grounds and exposed lobster grounds, resulting in declines in velvet landings (Appendix 2). Observed increases in Q4 of undersized can be linked to the retraction of the fishery, with the movement of gear into sheltered inshore areas used by the winter fishery (See Succorfish Report: Coleman & Rodrigues, 2017).

As with brown crab, the discarding of velvets in 2016 due to non-marketability was recorded separately to that of undersized individuals (Appendix 4). The separation of the two discarding behaviours provides greater insight into both the behaviour of the fishery and the biological process underpinning these behaviours. Peaks within discarding behaviour follow clear seasonal trends, differing from the undersize interaction behaviour, with a peak in discarding occurring in August. This peak within the fishery can be linked to the primary moulting period (Hearn, 2004). Similar trends are exhibited in earlier years, especially 2015 where an overall high level of percentage discarding was recorded within Q3, with this summarily linked to moulting and the resulting non-marketability of the catch.

European Lobster European lobster undersize interaction was recorded at an overall average of 16% for the OSRP, with fluctuation recorded within years (39%: 2013, 23%:2014; 13%: 2015; 8%: 2016). Seasonality within the varying levels of undersize interaction was also recorded, with interaction levels following the seasonal nature of the fishery and peaks recorded within Q3 and Q4 (Appendix 3). This interaction cycle mirrors that of the commercial fishery (Appendix 1), indicating that the undersize proportion of the stock follows and is influenced by the same environmental variables. Subsequent further investigation into the nature of undersize interaction is explored later within the report, with further insight into the size distribution of undersize individuals reported (See section: Observed Report: Undersize Interaction).

Average discarding rates in lobsters was 4% (Appendix 4). This low level of discarding combined with low levels of undersize discarding behaviour potentially indicates that recruitment into the fishery is

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highly size related, with individuals typically >80mm before first capture (Appendix 11). The reason why lobsters could be released or classed as unmarketable could result from the discarding of v-notched individuals, however this is uncertain. Other reasons for discarding of lobsters could be the occurrence of multiple lobsters in creels, resulting in low levels of in-creel lobster mortality. Such interaction events sometimes result in severe maiming of individuals e.g. the loss of both claws making them commercially unmarketable.

Green Crab In the case of green crabs, low levels of undersize interaction were reported at <1%, with this low level a result of their low commercial value and subsequent limited targeting (Appendix 3). In regards to discarding, similar low levels of discarding were reported (1%), however slight seasonality is demonstrated within this fishery with a peak observed in June (Appendix 4). The reasons behind this apparent spike are purely speculative, however peaks in discarding in this time-period could be attributed to moulting. As a sublittoral species found in shallow inshore water at typically < 20m, this means moulting will occur far earlier in the year, potentially occurring within July due to seasonal fluctuations in SST (Lyons, et al 2012).

1.3. Non- Target Species Non-target species refers to all species that are not targeted commercially by the creel fishery. The description of species as non-target, as opposed to discard, is due to the subsequent retention of particular species on-board due to their use as bait within the fishery.

In the case of the logbook scheme, varying levels of non-target species interaction was recorded throughout the course of the OSRP. During this a total of 14 species were recorded with 10 demersal fish species, 1 congridae, 1 elasmobranch and 2 crustacean species (Appendix 5).

Of these 14 species, Atlantic Cod (Gadus morhua) displayed the highest level of interaction of any recorded non-target species (n=3,703), with continued interaction reported throughout the OSRP (Table 7; Appendix 5). Initially limited amounts of reporting occurred in 2012/14 (Table 7), but greater reporting of this species was documented in 15/16 (Table 7). It is important to interpret this species as having high interaction rates within the fishery having been potentially under-reported in 2103/14 period of the OSRP. Of those individuals caught, they ranged from 235 – 536mm total length (TL). Sex specific information was not collected as gonad dissections were not carried out (OSF). Atlantic cod also presents the only species that is currently listed as vulnerable under IUCN red list (Sobel, 1996), with significant conservation measures in place, including reduced total allowable catch (TAC), and the implementation of a Scottish cod recovery zone.

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Table 7. Total number Atlantic Cod (Gadus morhua) reported in the logbooks by year (2013-2016)

Atlantic Cod (Gadus morhua) No. Caught No./100 creels 2013 65 0.09 ± 0.1 2014 160 0.002 ± 0.002 2015 912 0.57 ± 0.56 2016 2,566 1 ± 1.02

Common Dogfish (Scyliorhinus caniculus) was the second most highly reported non-target species reported within the logbook scheme (n =1,844: Appendix 5). Similar to Atlantic cod, reduced reporting of common dogfish occurred within 2013 and 2015 (Table 8; Appendix 5), however interaction events were recorded more frequently in 2014/2016. In relation to identifying trends within interaction rates, the appearance of peaks can be identified within Q3 across all years (Appendix 8). These peaks could be attributed to changes in fishing patterns and the targeting behaviours of fishers, with the peak coinciding with the brown crab fishery (OSF, 2016). Of those individuals caught, they ranged from 373mm – 783mm TL with no data collected on the sex of the individuals. Based on the known reproductive biology of the species and the limited size frequency recorded, it indicates that individuals are caught prior to becoming sexually mature (Henderson & Casey, 2001). This identifies the potential for increased mortality due to the opportunistic removal of the species as bait. It is therefore recommended that the interaction rates of this species continue to be monitored as part of OSF’s ongoing work, and further regional research be conducted on this non-target species.

Table 8. Total number of Common Dogfish (Scyliorhinus caniculus) reported in logbooks by year (2013-2016)

Common Dogfish No. Caught No./100 creels 2013 95 0.13 ± 0.27 2014 414 0.004 ± 0.005 2015 233 0.14 ± 0.13 2016 1102 0.4 ± 0.5

Similar to Atlantic Cod and Common Dogfish, demersal species dominate reported non-target species within the logbook scheme, due to their financial benefit in relation bait usage. This is further highlighted by the other species which are recorded in high numbers being bait species: Ling molva molva (n=513) and Wrasse sp.(n-= 1403), whilst species with no bait value or limited interaction are not recorded.

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In comparison to previous years, high numbers of curled were reported in 2016 (Appendix 5), with this species historically only recorded within the observer programme. The subsequent reporting of this species highlights potential substantial increases in population numbers, with fishermen remarking on the loss of catch due to octopus predation (person.comm). Reason behind the increases in abundance could be attributed to natural occurring predator prey cycles, with increases in prey abundance resulting in increased predator survival and overall predator density within the ecosystem. Coincidently this increase in octopus corresponds to fishermen’s comments relating to substantial increases in juvenile brown crab within inshore waters over previous years. Furthermore the subsequent decline in large predatory fish within inshore waters could have contributed to increased abundance, with increases in abundance documented worldwide linked to decreases in large predatory fish biomass (Doubleday et al, 2016)

1.4 Summary In Summary, the logbook programmes provide valuable insight into the spatial and temporal fishing pattern of the Orkney inshore fleet. The necessity of detailed fisheries dependant data has become of increased importance, with OSF looking to build upon the data collected throughout the course of the next OSRP. A number of additional avenues of research have been highlighted, including further research into the interaction of non-target species and the production of a standardised LPUE time series

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2. Observer Report

2.1 Overview The OSF observer programme involved the participation of fishermen and marine scientists. Through observer trips OSF collected trip-specific information, providing a snapshot of fishing activity within both a spatial and temporal context. Information collected included; effort, retained catch, interaction with non- target species and commercial species discards.

Figure 1 Orkney stock assessment area, comprising of four ICES rectangles.

121 trips were conducted throughout the course of 2013 – 2016 across a total of 16 vessels of differing sizes (vessel total length>10m & <10m) within the Orkney stock assessment area (Figure 1). Vessels targeted a combination of brown crab, European lobster, velvet crab and green crab, with the primary target species of each trip depending on a combination of environmental and market value factors. These

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16 vessels represented 15% of the total licenced creel fishing vessels within Orkney, (107 Vessels: Scottish Government, 2015). A total of 30,036 creels were observed across 1,150 ropes over the project time-period (Table 9).

Boat participation remained steady within the later years of the project (2015/2016), with large improvements made from the first two years. This increase in participation can be attributed to greater outreach activities being undertaken within the project along with an increase in manpower within 2015- 2016. Overall vessel coverage mirrored a similar trend to that of vessel participation with both 2015 and 2016, demonstrating high spatial coverage, with the exception of reduced coverage in ICES rectangle 46E7 in 2016. The reduced coverage within these areas can be attributed to fewer fishermen participating within the observer component of the OSRP, however coverage within this area is supplemented by vessels’ participation within the logbook and succorfish aspect of the OSRP.

Typically vessel data is separated in accordance to vessel size, however in this case vessel size was seen not to play an important part in the number creels deployed per trip, with vessels at both <10m and >10m deploying a similar number of creels per trip (2016: <10m – 275 creels per trip; >10m – 280 creels per trip). Therefore, all observer trips regardless of vessel size have been amalgamated. Additional further analysis into the key influencing variables of the inshore creel fishery will be explored.

Overall temporal changes in creel deployment per trips are seen not to differ considerably from 2014 - 2016. Average creel numbers per rope is seen to be consistent, with variability between years reducing with increased sampling effort. Consequently, a similar trend is observed within the average number of creels per trip, with variability reducing over time. Whilst variation in creels per trip reduces, the observed variation in the number of creels per rope and trip can be attributed to a combination of factors. These variables include grounds on which the fishery operates or biological characteristics of the stocks. In situations where fishing grounds are less productive increased effort (CPUE) would be required to extract similar returns to that of a more productive region. Temporal and spatial fluctuations in stock density also cause variation in returns and can result in increased effort to extract similar returns over varying time frames or reduced effort due to scarcity.

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Table 9 Total observer coverage achieved within the OSRP (2013-2016) and coverage associated within each ICES rectangle

2013 2014 2015 2016 2013 -2016

No. Vessels Sampled 1 6 16 15 16

ICES 46E6 - 4 17 9 30 ICES 46E7 - - 3 - 3 ICES 47E6 - - 7 5 12 ICES 47E7 - 2 5 13 20 ICES 46E6/47E6 2 - 23 20 45 ICES 46E7/ 47E7 - - 3 0 3 ICES 47E6 / 47E7 - - 2 6 8

Total No. Creels Observed - 1,646 15,204 13,186 30,036

Avg. No. Creels Per Rope - 27 ± 15 29 ± 8 28 ± 9 28 ± 9 Avg. No. Creels Per Trip - 274 ± 179 253 ± 105 280 ± 102 265 ± 108

2.2 Observed Catch Composition & Cath per Unit effort

Brown Crab Brown crab made up 74% of total catch compositions observed during OSRP observer trips. Total observed catch composition remained constant over the OSRP observe programmes with similar levels observed between years (77% 2015; 82% 2014). Variability in the CPUE fluctuates through the course of the sampling period with variation in CPUE linked to a combination of environmental and fisher driven variables. Observed CPUE remained constant throughout the OSRP observer programme with its peak in May (Table 10), highlighting the constant interaction of brown crab within the inshore fishery year round, irrespective of changes in primary target species.

Table 10 Monthly changes in observed brown crab catch per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 5,252 2,017 7,910 20,925 24,109 26,805 11,890 15,431 16,919 2,235 CPUE/100 548 974 604 385 403 411 426 410 658 573 Creels

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European Lobster European lobster made up 3% of the total catch composition observed during OSRP observer trips, with total catch contribution remaining stable fluctuating by 1% annually since 2013 (2% - 2015; 2% - 2014). CPUE was observed to fluctuate throughout the observer programme, with these fluctuations known to be heavily attributed to changes in environmental conditions dictating the nature of the lobster fishery, especially water temperature (Lizárraga et al, 2015). This is evident with the peak interaction within the fishery occurring in August, mirroring the peak in sea bottom temperature (OSF – Sea Bottom Temperature Project (unpublished))

Table 11 Monthly changes in European lobster catch per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 49 5 121 184 420 1,847 631 797 57 67 CPUE/100 5 2 9 3 7 28 23 21 2 17 Creels

Velvet crab Velvet crab made up 21% of total observed catch composition during OSRP observer trips. With little variability between years (21%; 2015, 24%: 2014). Peak observed interaction is observed in October and November, with a gradual increase in CPUE seen in the previous quarter. This variability in CPUE data collected can be attributed to the vessel on which observer trips were conducted, with some trips conducted on vessels targeting solely brown crab and lobster in Aug/Sept and Dec. This trend is visible in previous years (Appendix2) as is the trend also observed with changes in velvet catches recorded in the logbook scheme (Appendix 1& 2)..

Table 12 Monthly changes in velvet crab catch per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 959 NA 207 1309 5439 5988 6515 2789 3764 -

CPUE/100 95 NA 1,226 345 408 95 18 34 326 - Creels

Green Crab Green crab made up only 2% of the catch composition during OSRP observer trips. The low percentage can be attributed to it being predominantly a winter fishery, with a small number of <10m vessel targeting

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this fishery all year round. However, in the cases in which it is targeted the species is removed in large numbers due to its low commercial value and the subsequent high volume needed to make it financially viable

Table 13 Monthly changes in green crab catch per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught - - - - 2458 - - - 10 - CPUE/100 - - - - 3072.5 - - - 21.7 - Creels

2.3 Observed Landings Composition & Landing Per Unit Effort

Brown Crab Brown crab comprised 59% of the total observed landings composition during OSRP observer trips. In the case of those caught only 33% were retained. LPUE fluctuated through the course of the observer period, with peaks in LPUE occurring within March and November. Subsequent decreases in LPUE in September/October can be associated with both the targeting behaviour of the fishery and the subsequent movement of gear into more sheltered areas in time for the winter fishery. The subsequent movement of gear to sheltered winter grounds results in increased interaction with the male proportion of the brown crab stock, causing an observed spike in the landings. In comparison to previous years, overall LPUE has remained constant in comparison to 2015 (62%),

Table 14 Monthly changes in brown crab landing per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 2,403 775 1,028 8,239 8,111 9,596 4,142 3,509 5,333 160

CPUE/100 251 374 79 151 135 147 149 93 207 41 Creels

European Lobster European lobster composed 3% of the total observed landings composition during OSRP observer trips. However of those caught only 55% of those were retained. LPUE for lobster is seen to follow a highly seasonal pattern with the peak fishery occurring in August and a second peak occurring in December. The high seasonal nature of the lobster fishery is well documented within the logbook programme (Appendix1 &2) and is known to coincide with the increase in sea bottom temperature (Lizárraga et al, 2015). As a

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result the fisheries length can vary annually from June – September due water temperature. The secondary peak in December illustrated here however should be interpreted cautiously, as these estimates are based on one observer trip and are therefore not representative.

Table 15 Monthly changes in European lobster landing per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 33 3 74 122 294 1,029 289 322 35 53 CPUE/100 3 1 6 2 5 16 10 9 1 14 Creels

Velvet Crab Velvet crab account for 33% of the observed LPUE from 2016, in comparison with observations made in 2015 (36% LPUE) and remaining an important component of the Orkney inshore fishery. Retention rates were high with 52% of observed individuals retained. Peaks in LPUE occurred in the final quarter of the year (Oct – Dec: Appendix 1). Additionally, a secondary peak is observed in May. This peak is mirrored in a decline in brown crab LPUE and also recorded within the catch compositions of the logbook fleet (Appendix 2).

Table 16 Monthly changes in velvet crab landing per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 617 - 1434 3219 2819 429 875 6335 9213 - CPUE/100 64 - 110 59 47 7 31 168 358 - Creels

Green Crab Green crab represented 2% of the total LPUE. This low percentage is anticipated due to green crab being target predominantly in Q3 and subsequently in Q1 of the following year due to necessity. However, a number of smaller inshore vessels do target this fishery year round. In this instance, green crabs are landed in large quantities, due to their low commercial value resulting in a high volume fishery.

Table 17 Monthly changes in green crab landing per 100 creels (Jan – Dec 2016)

Mar Apr May Jun July Aug Sept Oct Nov Dec No. Caught - - - - 679 - - - 10 -

CPUE/100 - - - - 848.8 - - - 7 - Creels

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2.4 Observed Discard Composition& Discard Per Unit Effort (DPUE)

Brown Crab Brown crab accounted for 83% of those species discarded during OSRP observer trips, indicating high levels of undersize interaction within the fishery, with similar values observed across years (84% 2014; 84% 2015; 82% 2016). Overall 67% of observed brown crab was discarded whilst DPUE varied between months, with the highest discards observed in Q1 and Q4. High discards level during these time periods can be attributed to the movement of fishing gear into more sheltered inshore areas used during the winter fishery, with these areas being important juvenile undersize brown crab nursery grounds (Heraghty, 2013; Bakonyi, 2016). The discarding behaviour observed is similar to that of the logbook fleet over the same time period. Continued analysis on the size distribution of discarded crab provides an insight into the population structure of brown crab within the inshore fishery. The results of 2016 highlight the continued possibility of identifying recruitment cohorts into the fishery, with a post recruitment cohort identified at 86-92mm (Appendix 9), similar to the cohort identified in 2015. Of those individuals sampled as discards, size frequency ranged from 23 – 212mm CW. The discarding of individuals greater than 140mm CW can be attributed to unmarketability including, white or black spot crabs. The average size of females less than 140mm was 108.2mm with males at 109.7mm CW and where average size was calculated on individuals less than 140mm to provide insight into true undersize interaction, reducing bias caused by discarding due to the unmarketability of larger crabs. In comparison to 2015 (Appendix 9) less brown crabs >80mm were encountered in 2016 reducing the ability to detect recruitment cohorts. This lack of individuals >80mm can be attributed to less observed trips conducted on vessels targeting velvet crabs over the course of the year, thereby reducing the opportunity to sample this proportion of the population due the high degree of habitat overlap between the two species.

Table 18 Monthly brown crab discards per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 2,849 1,242 6,882 12,686 15,998 17,209 7,748 11,922 11,586 2,075

CPUE/100 297 600 526 233 267 264 278 317 451 532 Creels

European Lobster European lobster made up only 2% of those species discarded during OSRP observer trips. Of those observed 45% were discarded, with discard peaks observed within August. This coincides with peak

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LPUE, indicating that there is a general increase in stock movement during this time-period. Those individuals discarded ranged from 55 - 140mm CL (Appendix 11) with the average discarded female being 86.2mm CL and male 79.65mm CL, the inclusion of individuals <89mm being attributed to v- notched females. This size distribution indicates that discards are dominated by individuals ranging from 74-88mm, accounting for 80% of discards whilst individuals >70mm are far less common. The reduced interaction of these smaller individuals within commercial creels makes recruitment inference difficult, as undersize individuals are underrepresented within the catch. The reasons behind this could be the increased risk of predation removing smaller lobsters from the creels and fundamental differences in their behaviours. Another reason could be the habitat preferences of undersize and juvenile lobsters which could favour areas out-with the range of the where the typical fishery occurs.

Table 19 Monthly European lobster discards per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 16 2 47 62 126 818 342 475 22 14

CPUE/100 2 1 4 1 2 13 12 13 1 4 Creels

Velvet Crab Velvet crab was responsible for 12% of total discards observed during OSRP observer trips. 48% Of those observed that were discarded, females dominated the discard composition with an approximate female to male ratio of 29:21, with an average size of females being 63.8mm CW, and males 64.54mm CW (Appendix 10). In 2016 discards are dominated by individuals at 65mm and this can be attributed to the increase in MLS of 65 to 70mm which came into force in March 2016. This has shifted the discarding behaviour of the fishery, whereas in 2015 velvet discards were limited to those <65mm.

Table 20 Monthly velvet crab discards per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec

No. Caught 294 - 1103 1303 2346 664 1364 2751 3285 - CPUE/100 31 - 84 24 39 10 49 73 128 - Creels

Green Crab Green crab comprised 13% of the total discards and this high percentage can be attributed to the low commercial value and subsequent automatic discarding by fishers. Additionally, even within the fishery targeting the species, high levels of discarding occurs. This can be due to the sheer volume of individuals

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caught, enabling fishers to be highly selective. Additionally, the peak in the contribution to discards can be attributed to the enforcement of a MLS in 2015, prior to when no MLS existed for this species and resulting in greater recording of the species interaction as both a target and discarded species. Of those species discarded, individuals range from 58 -78mm CW (Appendix 13), with the average female size being discarded at 63.2mm CW and males 65.2mm CW.

Table 21. Monthly green crab discards per 100 creels (Mar – Dec) throughout the OSRP

Mar Apr May Jun July Aug Sept Oct Nov Dec No. Caught - - - - 1,779 - - - 21 -

CPUE/100 - - - - 2,223.8 - - - 14.7 - Creels

2.5 Non- target Species. A total of 42 non-target species were observed at varying levels throughout the course of the OSRP observer programme which included; 7 crustacean species, 7 invertebrate species, 1 elasmobranch, 25 demersal fish species and 1 congridae specie (Appendix 6). Of those species caught, the level of observed interaction varied considerably between years. Peak interaction events of certain species were heavily influenced by environmental conditions relating to target species and subsequent fishing behaviour associated with that fishery. Of those species recorded by scientific observers all of those recorded within the index logbook fleet were also observed. In comparison to the index logbook fleet, a far greater number of species were subsequently recorded, with similar trends observed in previous year (Coleman & Rodrigues, 2016). The reasons behind the greater number of species recorded through the observer programme can in part be attributed to the lack of recording of species with little monetary worth to the fishermen, with those species recorded within the logbook providing fiscal worth as a bait species. Subsequently lesser valued invertebrate species are discarded without thought, hence the lack of their recording. In addition, the precision of recording undertaken by the observers is far greater than that of the logbook fleet, with the observer programmer recording bycatch as close to species level as possible. This level of precision increases the number of species recorded, for example, wrasse are recorded under the blanket term ‘Wrasse sp.’ within the logbook programme, however they are recorded as 4 different species within the observer programme.

Of the species observed a number were repeatedly caught with varying levels of interaction occurring within different temporal scales and the reasons behind their repeated interaction attributed to a number of environmental and fisher related variables. Of the crustacean species encountered, velvet crab, green crab and common hermit crabs had the highest interaction rates of all crustacean species (Appendix 6). In the

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case of velvet crabs, high levels of discards can be attributed to targeting behaviour of the fishery with velvets a common bycatch of the lobster fishery due to similar habitat preferences and subsequent fishery overlap. This is further highlighted by the large number of velvets recorded in July and August coinciding with the peak lobster fishery (Section Observer: European Lobster LPUE). Additionally, the recording of velvets as purely discards can be attributed to limited targeting of the species in general over this time- frame due to key biological process making them unmarketable, in this case moulting. During the moulting period large proportions of the fishery becomes unmarketable making it uneconomic. This targeting behaviour is mirrored within the logbook scheme, with the highest discard rates of non- undersized individuals occurring in August (See section: Logbook – Discards (Appendix 4).

Of the demersal species that exhibited high interaction rates with the inshore fishery, the Common Dogfish (Scyliorhinus caniculus) demonstrates a sustained level of interaction with the inshore fishery, with a slight peak exhibited in August (Appendix 8). This peak however should be interpreted cautiously due to potential sampling bias causing a peak within the monthly break-down. However, this species was frequently observed throughout the course of the OSRP (Appendix 6& 8) and under varying levels of observer effort, indicating high levels of interaction within the fishery. Under current conservation advice Common Dogfish are listed as a ‘least concern’ under IUCN classification (Ellis, 2009). Continued monitoring of this species however should be undertaken due to its slow growth rates and low reproductive output, making them vulnerable to excessive removal. For the first time in 2016, OSF trialled a detailed discard collection (DDC) protocol over two observed trips which involved the collecting of size-frequency and sex information where possible on discard species, predominantly demersal fish. Of the data collected common dogfish ranged from 373mm – 783mm TL. No data was collected on the sex of the individuals. Due to these factors, it is recommended that this species interaction with the fishery continue to be monitored.

The interaction of Atlantic Cod (Gadus morhua) continues to be observed within the fishery. The observations made are similar to those made in previous years (Coleman & Rodrigues, 2016; Coleman & Rydzkowski, 2015) and similar to records in the logbook scheme. From the data collected via DDC, Atlantic Cod ranged from 235 – 536 but sex specific information was not collected as gonad dissections were not carried out. Additionally, two colour morphs are seen to interact within the fishery, “typical” and “red” cod. Red cod are typically individuals of the species which inhabit close inshore waters and feed on prey items within the kelp forest, ingesting red pigmentation, resulting in this colour morph. There is however no differentiation between the two colour morphs in relation to stock identity. Due to international conservation efforts surrounding Atlantic and cod, the interaction of this species

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will continue to be monitored within the fishery. OSF will be looking at trialling DDC again in 2017 with the aim of collecting more information on the size and sex structure of this species.

V-notched lobsters are seen to interact within the fishery at low levels following similar behaviours and interaction cycles as that of the commercial fishery, with peak interaction between August and October (Appendix 8). Varying levels of interaction are seen over the course of the years with the density of the v- notched lobster being heavily dependent on the behaviour and voluntary v-notching of fishers (Appendix 5 & 6). Overall v-notched lobsters accounted for ±1.5% of total lobster observed in 2016. This is a substantial drop compared to 2015, with v-notch lobster accounting for ±4% of total lobsters observed. Overall however observed interaction rates forecast that approximately 1v-notched lobster is caught for every 150 creels.

2.6 Summary In summary, the observer program provides valuable detailed insight into the activities of the inshore Orkney fleet. Data gathered throughout the course of the OSRP observer programme provides the basis for future research regarding both target species and non-target species. A number of research avenues have been highlighted, primarily relating to the interaction rates of non-target species and the process of collecting more detailed information relating to their catch composition and baseline biological characteristics. Future OSF work will look to build upon the outcomes of the work presented in its ongoing research.

3. Conclusion The OSRP logbook and observer programme has provided essential baseline information that can be used towards progressing the fishery towards sustainable management. The use of and value of the baseline data cannot be underestimated with the time-series data sets collected within the project being some of the most detailed within Scotland. In regards to the logbook programme, OSF will be using the information collected to produce a LPUE time-series of the fishery. This information will be used to monitor the health of the fishery, detect declines within stock biomass and changes in overall fishing effort.

OSF will continue to expand the logbook programme, either through the use of its own programme or in partnership with the new Marine Scotland logbook format. OSF will provide greater overall coverage across differing vessel types and sizes and provide the opportunity to monitor the fishery by ICES rectangle or smaller. OSF will continue to assess and monitor the interaction rates of non-target species within the new 4-year project incorporating non-target species sampling as a primary component of its research.

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References: Bakonya, L. (2016). Mapping the Habitat of Juvenile Edible Crabs ( L.) in the Intertidal areas of Mainland Orkney. MSc Thesis. Heriot-Watt University. Coleman, M. and Rodrigues, E. (2016). Orkney Shellfish Project End of Year Report: January – December 2015. Orkney Sustainable Fisheries Ltd., p.86. Coleman, M. and Rydzkowski, K. (2015). Orkney Shellfish Research Project - End of Year Report 2014. Orkney Sustainable Fisheries Ltd., p.38. Duncan, C. (2015) Size of Maturity and Population Dynamcis of Green Crasb () in Mainland Orkney, Scotland. Unpublished MSc Thesis. Heriot- Watt University.

Ellis, J., Mancusi, C., Serena, F., Haka, F., Guallart, J., Ungaro, N., Coelho, R., Schembri, T. & MacKenzie, K. 2009. Scyliorhinus canicula. The IUCN Red List of Threatened Species 2009: e.T161399A5415204. http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T161399A5415204.en.

European Commission (EC) (1998), “For the Conservation of Fishery Resources through Technical Measures for the protection of Juvenile Marine Organisms”. Council Regulation (EC) No.850/98.

Hearn, A. (2004). Reproductive biology of the velvet swimming crab, Necora puber (Brachyura: Portunidae), in the Orkney Islands, UK. Sarsia, 89(5), pp.318-325. Henderson, A. and Casey, A. (2001). Reproduction and growth in the lesser-spotted dogfish Scyliohinus canicula (Elasmobranchii: Scyliorhinidae) from the west coast of Ireland. Cahiers de Biologie Marine, [online] 42, pp.397-405. Available at: http://www.vliz.be/imisdocs/publications/289183.pdf. Heraghty, N. (2013). Investigating the abundance, distribution and habitat use of juvenile Cancer pagurus (L.) of the intertidal zone around Anglesey and Llŷn Peninsula, North Wales (UK).. MSc Thesis. Bangor University: Fisheries & Conservation report No. 29, Pp.75. Lizárraga-Cubedo, H., Tuck, I., Bailey, N., Pierce, G., Zuur, A. and Bova, D. (2015). Scottish lobster fisheries and environmental variability. ICES Journal of Marine Science: Journal du Conseil, 72(suppl 1), pp.i211-i224.

Scottish Government (2015). “Scottish Sea Fisheries Statistics 2014”, Marine Scotland. http://www.gov.scot/Resource/0048/00484499.pdf

Scottish statutory instruments (2016). “The Orkney Islands (Landing of Crabs and Lobsters) Order 2016”. Sea Fisheries, Conservation of Sea Fish 2016 No. 50

Sobel, J. 1996. Gadus morhua. The IUCN Red List of Threatened Species 1996: e.T8784A12931575. http://dx.doi.org/10.2305/IUCN.UK.1996.RLTS.T8784A12931575.en.

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Zoë A. Doubleday, , Thomas A.A. Prowse, Alexander Arkhipkin, Graham J. Pierce, Jayson Semmens, Michael Steer, Stephen C. Leporati, Sílvia Lourenço, Antoni Quetglas, Warwick Sauer, Bronwyn M. Gillanders. 2016. Global proliferation of . Current Biology, 26,10. DOI: http://dx.doi.org/10.1016/j.cub.2016.04.002.

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Appendix

Appendix 1 Log transformed landing per unit effort per 100 creels reported within the logbook scheme (2013 - 2016)

1

Appendix 2 Monthly total catch compositions per commercial important crustacean species reported by the logbook fleet by year (2013 – 2016)

2

Appendix 3 Monthly percentage undersize interaction rates of commercially important crustacean species reported by the logbook fleet (2012 – 2016)

3

Appendix 4 Monthly discard rates of commercially important crustacean species (Jan – Dec 2016)

4

Appendix 5 Total recorded interaction of non-target species reported by the logbook fleet (2014 -2016)

Total No. Caught (CPUE/100 Creels) 2014 2015 2016

Common Dogfish 414 (0.004 ± 0.005) 233 (0.14 ± 0.13) 1102 (0.4 ± 0.5) Scyliorhinus caniculus

Wrasse 195 (0.002 ± 0.002) 109 (0.06 ± 0.07) 1099 (0.4 ± 0.2) Labridae sp.

Atlantic Cod 160 (0.002 ± 0.002) 912 (0.57 ± 0.56) 2566 (1 ± 1.02) Gadus morhua

Haddock - 1 (<0.0006± 0.001) 21 (0.008 ± 0.008) Melanogrammus aeglefinus

Conger Eel 152 (0.001 ± 0.002) 95 (0.06 ± 0.06) 225 (0.09 ± 0.07) Conger conger

3 Brd Rockling 14 (<0.001 ± <0.001) 2 (0.001 ± 0.004) 219 (0.08 ± 0.05) Gaidropsarus mediterraneus

Wolf Fish - - 1 (0.0003 ± 0.002) Anarhichas lupus

Curled Octopus 17 (0.02 ± 0.05) 3 (0.001 ± 0.003) 304 (0.11 ± 0.11) cirrhosa

Sea Scorpion - 28 (0.01 ± 0.03) 123 (0.04 ± 0.04) Taurulus bubalis

Comper 43 (0.04 ± 0.07) 98 (0.03 ± 0.2) 52 (0.02 ± 0.1) Serranus cabrilla Monkfish - 1(0.0003 ± 0.001) - Lophius piscatorius Ling - 111 (0.04 ± 0.09) 402 (0.1 ± 0.1) Molva molva

Saithe - - 1 (0.0003 ± 0.001) Pollachius virens V-Notch 38 (0.04 ± 0.04) - 1 (0.0003 ± 0.002) Hommarus Gammarus

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Appendix 6 Total number of non-target species recorded during observer trips (2014 -2016)

Total No. Caught (CPUE/100 Creels) Species 2014 2015 2016 Velvet Crab 1403 (91.04 ± 2.03) 859 (5.64 ± 0.04) 3288 (24.94 ±18.46) Necora puber Green Crab - 1970 ( 12.95 ± 0.11) 515 (3.91 ± 6.56) Carcinus meanas Harbour Crab - 538 (3.53 ± 0.03) 38 (0.29 ± 0.02) Liocarcinys depurator Common Hermit Crab 1 (0.06 ± <0.001) 55 (0.36 ± 0.01) 1804 (13.68 ± 0.55) Pagrus bernhardus Majidae Sp. 11 (0.71 ± 0.006) 115 (0.75 ± 0.01) 71 ( 0.5 ± 0.01) Squat Lobster - 6 (0.03 ± 0.08) 3 (0.03 ± 0.06) Munida rugosa

Nephrop - 7 (0.04 ± 0.06) -

V-Notch European Lobster 21 (1.36 ± 0.012) 66 (0.43 ± 0.5) 31 (0.33 ± 0.25) Common Star Fish 4 (0.25 ± 0.002) 165 (1.08 ± 0.9) 140 (1.35 ± 1.06) Asteria rubens Sun Star 3 (0.19 ± 0.002) 100 (0.65 ± 0.9) 49 (0.52 ± 0.44) Crossasteer papposus Cushion Starfish - 6 (0.03 ± 0.06) 14 (0.15 ± 0.1) Asteria gibbosa Seven Armed Starfish - 1 (0.006 ± 0.05) 1 (0.01 ± 0.008) Luidia ciliaris Whelk 24 (1.55 ± 0.01) 294 (1.93 ± 1.37) 629 (6.73 ± 5.26) Buccinum undatum Sea Urchin 13 (0.84 ± 0.002) 151 (0.99 ± 0.79) 175 (1.87 ± 3.12) Echinus esculentis Curled Octopus 2 ( 0.1 ± 0.2) 60 (0.3 ± 0.77) 63 (0.6 ± 0.58) Eledone cirrhosa Sea Scorpion 12 (0.77 ± 1.07) 155 (1.01 ± 0.11) 104 (1.14 ± 0.58) Taurulus bubalus Comber - - 7 (0.07 ± 0.16) Tad Pole fish - - 2 (0.02 ± 0.03) Raniceps raninus Common Dogfish 127 (8.24 ± 5.15) 539 (3.54 ± 3.77) 317 (3.39 ± 2.4) Scyliorhinus caniculus

Ballen Wrasse 19 (1.2 ± 1.86) 206 (1.35 ± 0.9) 142 (1.52 ± 0.8) Crenilabrus melops

Goldsinny Wrasse 1 (0.06 ± 0.2) 8 (0.05 ± 0.14) 5 (0.04 ± 0.05) Ctenolabrus rupestris Cuckoo Wrasee - 11 (0.07 ± 0.04) 26 (0.19 ± 0.2) Labrus mixtus

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Rock Cook - - 1 (0.007 ± 0.008) Butterfish 1 (0.06 ± 0.07) 7 (0.04 ± 0.05) 29 (0.2 ± 0.25) Pholis gunnellus Atlantic Cod 25 (1.6 ± 1.3) 417 (2.74 ± 1.17) 364 (2.76 ± 3.8) Gadus morhua Pouting - - 1 (0.007 ± 0.014) Trisopterus luscus Poor Cod - 3 (0.02 ± 0.05) 5 (0.03 ± 0.06) Trisopterus minutus Haddock - 6 (0.39 ± 0.04) 7 (0.05 ± 0.05) Melanogrammus aeglefinus Pollack - 24 (0.15 ± 0.25) 7 (0.05 ± 0.05) Pollachius SP. Coley - 1 (0.006 ± 0.012) 43 (0.32 ± 0.24) Pollachius virens Blue Whiting - - 5 (0.037 ± 0.03) Trisopterus minutus Red Gurnard - - 1 (0.007 ± 0.008) Chelidonichthys cuculus Conger Eel 40 (2.5 ± 6.1) 65 (0.4 ± 0.27) 57 (0.43 ± 0.8) Conger conger Three Bearded Rockling 34 (2.2 ± 1.9) 102 (0.67 ± 0.4) 79 (0.59 ± 0.5) Gaidropsarus vulgaris Ling 7 (0.45 ± 0.66) 48 (0.3 ± 0.15) 38 (0.28 ± 0.68) Molva molva Tusk - 4 (0.02 ± 0.02) 10 (0.07 ± 0.07) Brosome brosome Dab - 499 (3.3 ± 3.4) 56 (0.42 ± 0.75) Limanda limanda Flounder 1 (0.06 ± 0.2) 1 (0.006 ± 0.008) 1 (0.007 ± 0.008) Platichthys flesus European Plaice - 86 (0.56 ± 0.76) 3 (0.02 ± 0.02) Pleuronectes platessa Topknot - 3 (0.01 ± 0.05) 3 (0.22 ± 0.04) Zeugopterus punctatus Lemon Sole - - 1 (0.007 ± 0.15) Microstomus kitt Flatfish sp. - 9 (0.06 ± 0.06) 8 (0.06 ± 0.069)

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Appendix 7 Average LPUE of commercial species recorded by Observers (2014 -2016)

Appendix 8 Average LPUE per year for Atlantic Cod, Common Dogfish and V-notch lobsters recorded by the observer programme (2014 -2016)

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Appendix 9 Catch frequency of brown crab below minimum landing size (140mm carapace width) and discarded during observer trips (2015 -2016)

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Appendix 10 Catch frequency of velvet crabs below minimum landing size (2015 – 65mm CW; 2016 – 70mm CW) and discarded during observer trips (2015 – 2016)

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Appendix 11 Catch frequency of European lobster below minimum landing size and discarded during observer trips (2016)

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Appendix 12 Catch frequency of green crabs below minimum landing size and discarder during observer trips (2016)

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