5

Rapp. P.-v. Réun. Cons. int. Explor. Mer, 176: 5. 1979.

FOREWORD

The concern generated within the main Atlantic salmon producing countries in the North Atlantic following the rapid growth of the West Greenland salmon fishery in the early 1960s, and the great scientific interest in gaining more knowledge of salmon during its sea phase led to steps being taken by the International Commission for the Northwest Atlantic Fisheries (ICNAF) and the International Council for the Exploration of the Sea (ICES) at their Annual Meetings in 1965 to organize an international scientific appraisal of this fishery development, with special reference to its effects on the salmon stocks and fisheries in home waters. A scientific Working Party, the ICES/ICNAF Joint Working Party on North Atlantic Salmon, with member­ ship from all North Atlantic countries with Atlantic salmon interests was established to undertake this task. The first meeting of the Working Party was held in 1966 and subsequent meetings were held each year thereafter up to 1974, their results being reported to the Annual Meetings of ICNAF and ICES respectively (ICES Cooperative Research Report Nos. 8, 12, 24, and 35 and Document CM 1974/M: 2). At the time when the Working Party was established, little was known about the biology of the Atlantic salmon during its sea phase. Hence, in addition to the collection of information on the characteristics and development of the West Greenland fishery itself, one of the Working Party’s most important tasks was the development of coordinated data collection and research programmes on aspects of its biology and population dynamics, especially those of direct relevance to the assessment of fishery effects. These programmes included regular monitoring of the distribution, size, age and sex compositions of catches taken in the West Greenland and home- waters fisheries, smolt tagging in home waters, investigations of scale characteristics and bio­ chemical properties of salmon of different home-waters origin in the West Greenland stock, studies of their feeding and growth, and investigations of their rates of exploitation in the home- waters fisheries. Amongst the most important of these cooperative programmes, however, was the ICES/ICNAF Tagging Experiment at West Greenland in 1972. This experiment which was funded by the countries most concerned and organized by members of the Working Party, provided vitally important information on the home-waters origin and destination of salmon in the West Greenland stock and a much more comprehensive data base for the assessment work. Although the results of these research programmes were presented in working documents to meetings of the Working Party and are summarized in its reports, most of the detailed work has remained unpublished. In view of their important contribution to the advancement of our knowledge of North Atlantic salmon biology and population dynamics, it was decided at the Annual Meeting of ICES in 1974, that the main items of this work should be published by the Council in a volume of the Rapports et Procès-Verbaux series. The contributions in this volume deal with various aspects of the work organized by the Joint Working Party in pursuing its remit. They cover aspects of the West Greenland fishery itself, the biological characteristics and origin of the exploited stock, the ICES/ICNAF Tagging Experiment at West Greenland in 1972 and the assessment of the effects of the West Greenland fishery on home-waters stocks. The volume should be read in conjunction with the reports of the Working Party referred to above.

B. B. P a r r is h Sv. Aa. H o r s t e d 82

Rapp. P.-v. Réun. Cons. int. Explor. Mer, 176: 82-92. 1980.

REVIEW OF NORTH AMERICAN SMOLT TAGGING TO ASSESS THE ATLANTIC SALMON FISHERY OFF WEST GREENLAND

C. P. R u g g l e s Montreal Engineering Co. Ltd. P.O. Box 3478 South, Halifax, B3J 3J1, and

J. A. R i t t e r Fisheries and Marine Service, Resource Development Branch Environment Canada, P.O. 550, Halifax, Nova Scotia B3J 2S7, Canada

INTRODUCTION Although occasional smolt tags have been recaptured Horsted (1971), Pyefinch (1969) and Saunders etal. off the east coast of Greenland, this review deals only (1965) have described the development of the Atlantic with smolt tags recovered in the West Greenland salmon (Salmo salar) fishery off West Greenland. The fishery. recapture of tagged salmon from European and North American rivers provided an early indication that the DESCRIPTION OF TAGGED SMOLTS fishery was dependent upon stocks from a variety of Between 1959 and 1971 inclusive, a total of 1894000 rivers in both North America and Europe. Sub­ hatchery and 259800 wild smolts was tagged and sequent tag recaptures have verified that most of the distributed into various rivers in North America rivers contributing to this fishery are located in the (Table 55). Tagged smolts emigrated from rivers British Isles and in Canada. For details about the situated all along the North American Atlantic coast first recaptures and for European tagging experiments, from as far south as the Connecticut River, USA, see A. Swain, 1980. to the Sandhill River in Labrador (Fig. 24). Sixty Early in 1965 the ICES/ICNAF Joint Working per cent of the wild smolts tagged were from the Party on North Atlantic Salmon was established to , . This river was also evaluate the effects of the Greenland fishery on the release site for 224100 or close to 12 per cent of member country salmon stocks. The Working Party the hatchery-reared smolts. has published four reports (Anon., 1967; 1969; 1971; Wild smolts were from 15 different rivers and 1973). One important component of these earlier hatchery-reared smolts were progeny from adults col­ analyses was the information provided by recapture lected in six rivers. Three other sources of hatchery- of salmon tagged in North America and Europe as reared smolts were from adults collected in the Chaleur smolts. The Working Party noted large variations in Bay near New Mills, New Brunswick, and off the recapture rates at West Greenland from different mouth of the Cascapedia River near Maria, , smolt tagging experiments and concluded that a more and in several rivers in Maine, U.S.A. detailed evaluation of tag returns was urgently needed. The purpose of this paper is to review North American smolt tagging conducted since 1959, with GENERAL REVIEW OF RECAPTURES a view to assessing their relevance in determining The first recapture of a salmon tagged as a smolt stock origins and mixing at West Greenland. Special from a North American river occurred in the Green­ emphasis is placed on smolt tagging experiments con­ land fishery on 10 October 1960. The fish had been ducted in 1970 and 1971, since their recapture in tagged on 22 M ay 1959, in the estuary of the M ira­ West Greenland waters coincided with extensive michi River, New Brunswick (Kerswill and Keenley- sampling of the Greenland catch in 1972 associated side, 1961). Since then 2248 recaptures off West with the ICES/ICNAF Salmon Tagging Experiment. Greenland from tagged salmon smolts originating Review of North American smolt tagging to assess the Atlantic salmon fishery off West Greenland 83

Sand Hill River> LABRADOR

100 20 0 Km

>almon River QUEBEC

Indian River -

yCascapedia NEWFOUNDLAND \River North Harbour River GULF OF ST. LAWRENCE

Restigouche Riven New Mills

River

.Miramichi Riverj

’ NEW BRUNSWICK s—\ >-> Big Salmon Saint John River River MAINE *-River Philip

West Rive]

NOVA SCOTIA

Medway* River ATLANTIC

'Connecticut River

Figure 24. Map showing the geographic range of tagged Atlantic salmon smolt releases in North America. from North American rivers between 1959 and 1971 smolts. Similarly, catches in West Greenland waters inclusive have been recorded. Over 90 per cent of are comprised largely of salmon that have spent one these tag recaptures were made approximately 1 year, winter at sea and designated throughout this paper 4 months, following emigration from the rivers as as one-sea-winter fish. Hatchery-reared salmon accounted for 75 per cent Table 55. Summary of tagged smolt releases in North of the North American smolt tags recaptured in the America from 1959 to 1971 inclusive Greenland fishery. Eighty-eight per cent of all the tagged smolts were hatchery reared. Tags returned No. of tagged smolts distributed Area of release from the West Greenland fishery represented 19 per Wild Hatchery cent of the total adult recaptures reported for the smolt releases. Although this figure cannot be taken Massachusetts, USA 0 7 500 as a direct measure of the impact of the West Green­ Maine, USA 0 382 900 land fishery on home-water fisheries, it does indicate Nova Scotia, Canada 21 100 370 100 Prince Edward Island, Canada 300 0 that this fishery accounts for a significant mortality New Brunswick, Canada 188 000 1 022 800 among both hatchery- and wild-tagged salmon. Eastern Quebec, Canada 0 110 700 However, in order to fully evaluate the impact of the Newfoundland, Canada 25 300 0 Greenland fishery, the absolute rather than the Labrador, Canada 25 100 0 relative fishing mortality should be considered in con­ 259 800 1 894 000 Total junction with the natural mortality occurring between 6* 84 C. P. Ruggies and J. A. Ritter

West Greenland and home waters. This is done by foundland fisheries. Adult tagging conducted in the various authors in this publication. The recapture same river during 1968 and 1969 yielded 49 recap­ rate of all hatchery-tagged smolts at West Greenland tures, 4 of which were reported from West Greenland. was 0-9 per thousand tagged. The corresponding According to the adult tagging study, salmon of the figure for wild-tagged smolts was 2-2. Salmon River do contribute to the Greenland fishery, Tagging experiments conducted in North America but probably not prior to spawning and anyway not indicate that not all salmon rivers contribute to the in sufficient numbers to be detected by the smolt West Greenland fishery (Table 56). While all genetic tagging experiment. stocks from which the hatchery-reared smolts origi­ The other four rivers that did not yield a tagged nated would appear to contribute to this fishery, only salmon to the Greenland fishery were similar to the 5 of the 10 rivers from which tagged wild smolts Salmon River in that they produced predominantly migrated and for which sufficient tag return data salmon that spawned first as one-sea-winter fish were available (a minimum of one tag returned from (grilse). This characteristic precludes their contri­ the Greenland fishery or in the case of no tag returns buting significantly to the Greenland fishery, since from this fishery a minimum of 25 adult recaptures) all fish caught in this fishery are at least one sea winter yielded returns from Greenland. in age and are caught so late in the year that they The Salmon River, Newfoundland was one of the will have added another sea winter prior to spawning, five rivers that did not contribute to the Greenland i.e., they cannot spawn as grilse. fishery according to smolt tagging data but did ac­ The pattern of successive spawnings, observed in cording to recaptures from adult tagging studies. For one of the four rivers not contributing to the Green­ instance, approximately 7600 tagged, wild smolts land fishery, the Big Salmon River, New Brunswick, emigrating from the Salmon River in 1968 contributed was predominantly that of consecutive years’ spawn­ no salmon to the Greenland fishery while yielding ing (i.e., [fish 'spawn year after year as opposed to 79 adult recaptures to the river escapement and New- every other year). This reduced further the chances of fish from this “grilse river” being taken in the Table 56. List of salmon rivers in North America for Greenland fishery. which smolt tag recapture data are available with comments on their contribution to West Greenland COMPARISON OF SMOLT RECAPTURES FROM fishery DIFFERENT NORTH AMERICAN STOCKS

Salmon river Comment In order to compare smolt tagging experiments in which large variations in recapture rates occurred, Sandhill R., Lab. Contributes the recaptures at West Greenland should be expressed Salmon R., Hare Bay, Nfld No evidence of contributing to as a percentage of total tags recaptured in all fisheries Greenland fishery according to and from home river escapements. This would enable smolt tagging data, but salmon tagged as adults in this river were direct comparison of a wide variety of experiments later recaptured off West Green­ using both wild and hatchery smolts and would land eliminate the need to account for the variable nature Indian R., Nfld No evidence of contributing to of smolt viability, tagging mortality and tag loss Greenland fishery North Harbour R., Nfld No evidence of contributing to between different experiments. Data from 47 separate Greenland fishery tagging experiments were available, which enabled Salmonier R., Nfld No evidence of contributing to this type of calculation to be made. Only tags re­ Greenland fishery covered from non-maturing one-sea-winter and Chaleur Bay, mixed stock Contributes from Maria, Que. multi-sea-winter salmon were analysed, i.e., matur­ Chaleur Bay, mixed stock Contributes ing one-sea-winter salmon (grilse) recaptures were from New Mills, N.B. excluded. Restigouche R., N.B. Contributes For this analysis the criteria for selection included Miramichi R., N.B. Contributes Caines R., P.E.I. Contributes the number of recaptures and, in the case of hatchery- River Philip, N.S. Contributes reared smolts, the rivers into which they were released. Margaree R., N.S. Contributes Only those smolt tagging experiments which yielded West R., Sheet Harbour, N.S. Contributes a minimum of 15 recaptures of salmon which were Medway R., N.S. Contributes Big Salmon River, N.B. No evidence of contributing to destined to or had spawned first as two- or three-sea- Greenland fishery winter salmon were selected. Tagging studies con­ Saint John R., N.B. Contributes ducted with hatchery-reared smolts released into Maine, mixed stock, Me Contributes rivers distant from their native streams were excluded Review of North American smolt tagging to assess the Atlantic salmon fishery off West Greenland 85

Table 57. Greenland recaptures of Atlantic salmon tagged as smolts from 12 selected North American stocks expressed as a percentage of total tags returned from all fisheries and present in river escapements for fish spawning initially or destined to as two- and three-sea-winter salmon. Greenland catch in tonnes is offset by one year to correspond to the year the tagged smolts would be subjected to Greenland fishing mortality

Stock or source ^------Year in which smolts were released------^ of broodfish 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971

Wild, NW Miramichi R., - - - 4 38 11 28 18 12 25 36 42 42 N.B. Wild, Miramichi R., 2 ------19 27 48 35 estuary, N.B. Hatchery, Miramichi R., ------23 10 8 N.B., early run Hatchery, Miramichi R., - - - - - — 16 20 10 21 23 - 20 N.B., late run Wild, Sandhill R., ------12 44 16 Labrador, Nfld Hatchery, New Mills, N.B. ______24 41 - - (from Chaleur Bay) Hatchery, Restigouche R.. ------9 23 36 47 - N.B. Hatchery, River Philip, ------56 48 75 N.S. Wild, Margaree R., ______25' — — — N.S. Hatchery, Medway R., ______42 N.S. Hatchery, St. John R., - - - - _ - _ _ 4 - 20 33 11 N.B. Hatchery, Maine, USA ------14 - 17 38 55 32 Greenland catch offset one year 60 127 244 466 1 539 861 1 370 1 601 1 127 2 210 2 146 2 689 2 040 because of their observed atypical ocean migration winter salmon, are compared for the smolt years 1959 patterns (Ritter, 1972). The most distant transplanted to 1971 inclusive in Table 57. groups of smolts included in the analysis were hatchery- The 12 selected stocks varied both year by year reared fish released in the Miramichi River, New between stocks and individually between years in the Brunswick, and originating from the Restigouche proportionate contributions they made to the West River adults and from broodfish collected in Chaleur Greenland fishery (Table 57). Proportionately more Bay near New Mills, New Brunswick. Smolts from of the River Philip hatchery-reared tagged smolts and this latter source are identified in this report as fewer of the Saint John hatchery-reared smolts were originating from New Mills broodfish. recovered in the Greenland fishery than were smolts One-sea-winter recaptures have been adjusted, con­ of the other stocks. sidering the location and time of capture to exclude Some of the year-to-year variations in the propor­ fish which, if not captured, we believe could have tionate contributions may be accounted for by the returned to their home rivers that same year as grilse. annual variations in the Greenland catch. Table 57 In addition, estimates have been made for unreported also records the Greenland catch, offset by one year tagged adults present in river escapements. The to correspond to the year the tagged smolts would be methods used in making these various estimates are subjected to Greenland fishing mortality. The pro­ presented as footnotes to Appendix Table I, which sum­ portion of tagged smolts recaptured off West Green­ marizes both tagging and recapture data for the 47 land, considering data for the 12 selected sources, experiments. varied directly with the size of the Greenland fishery From this basic pool of 47 smolt tagging experi­ over the period 1960 to 1972 inclusive. Although ments, 12 separate North American sources of smolts natural mortality between Greenland and home (stocks) were identified. The recapture rates of smolts waters will influence the relationship between the from these stocks in Greenland, expressed as a per­ Greenland catch and the proportion of Greenland centage of total tags returned from all fisheries and recaptures, the actual values observed suggest that present in river escapements for two- and three-sea- the relationship is nearly linear (Fig. 25). The rela­ 86 C. P. Ruggies and J. A. Ritter

7 5 - ALL STOCKS NORTHWEST MIRAMICHI STOCK -75

cn

0.84

CL O

50 -50

O

u. o z o

O 25 - -25 O

Q.

1000 2000 0 1000 2000

CATCH IN METRIC TONS Figure 25. Relation between Greenland catch and the proportions of North American stocks taken in the West Greenland fishery. Proportions taken in Greenland are of the total recapture of adult fish excluding grilse but including corrected numbers in the spawning escapement. Each individual proportion was plotted against the catch figure recorded for the year following smolt migration. Dates used in these plots are for smolt releases carried out between 1959 and 1971 as presented in Table 57.

tionship for the linear regression is T = —9-0843 + to take into account annual changes in ocean mor­ 0-0189 X with a correlation coefficient of 0-71 for tality or the non-reporting of tags in Greenland and 45 degrees of freedom. One might expect a somewhat home waters. None of these factors, we believe, would higher correlation if individual stocks were treated alter the conclusion that the proportion of tagged separately. In the case of all Miramichi stocks (wild North American smolts recaptured off West Greenland and hatchery-reared) the correlation coefficient was is a function, although not strictly linear, of the size 0-78 for 23 degrees of freedom. Wild smolt tagging of the Greenland fishery over the period 1960 through experiments conducted on the northwest Miramichi, 1972. when treated separately, exhibit the best correlation between the Greenland catch and tagged smolt re­ capture rates in the Greenland fishery (0-84). DISTRIBUTION OF NORTH AMERICAN SALMON Several factors could contribute to the variation AT W EST GREENLAND IN 1972 from the above regressions, the most obvious being It was possible to examine the distribution of North annual changes in proportion*of North,rAmerican American salmon in the West Greenland fishery in stocks in the Greenland catch (Lear and Sandeman, 1972 by comparing observed and expected tag returns 1980). Unfortunately data are not available on the from the fishery with respect to time and location of relative proportion of North American and European recapture. Jensen (1980) has reported the 1972 West salmon in the Greenland catch for most of the years Greenland catch by five-week time intervals and six treated in the regressions. Similarly, we were unable Greenland fishery areas, designated as follows: (A Review of North American smolt tagging to assess the Atlantic salmon fishery off West Greenland 87 map of Greenland is found on page 29 of this publi­ I - SEA-WINTER cation). to LU 50-1 Area I, 70°30'N - 68°40'N Disko Bank and coastal bank west of Disko ; I- CL Area II, 68°40'N - 66°35'N < O 20 - Store Hellefisk Bank; orLÜ Area III, 66°35'N - 65°25'N 25 Lille Hellefisk Bank Area IV, 65°25'N - 63°35'N Ld CJ Sukkertoppen Bank and Fylla Bank; cr LÜ 0 Area V, 63°35'N - 62°00'N CL Fiskenæs Bank and Dana Bank; Area VI, 62°00'N - 60°00'N Coastal Bank west and south of Arsuk

Tag recaptures were analysed by the chi-square 2 -SEA-WINTER method to determine randomness of distribution in iii the 1972 catch. 3 50-1 30 -i H We analysed for randomness of distribution in the CL Greenland catch for North American tagged salmon O< Ld of different sea ages. All North American smolt tag CE 2 0 - recaptures for which time and/or location of recap­ Ll _ 25 H tures in the 1972 West Greenland fishery was known 10- were included in this analysis. Direct comparisons of tag recaptures and salmon landings are presented in Ld O Appendix Table II. er I d Recaptures of tagged smolts for which neither loca­ CL i n ni i i h tion nor time of recovery was known were excluded, AREA while recaptures for which either the time or location of recovery was reported were fractionally allocated to location or period, respectively according to distri­ butions of the known recaptures. Although numbers of recaptures apportioned by this method were few (less than 10%), this treatment of data slightly accen­ Figure 26. Proportionate distributions by time and area of tuated frequency distribution patterns of tag recap­ North American smolt tags recaptured as one- and two-sea- winter salmon. tures. This procedure was utilized, however, since omission of those recaptures for which either the location or time was known would have unduly The area distributions of tagged smolts recaptured distorted the distribution patterns and imposed a as one- and two-sea-winter salmon were compared marked bias on the analysis. Because of this procedure with estimated catch distributions for similarly aged the numbers of recaptures are recorded to the nearest fish. These distributions were derived by apportioning tenth of a tag. the area catch figures as reported by Jensen (1980), North American tagged smolts recovered as one- according to sea age as presented by Munro and and two-sea-winter salmon respectively, showed dif­ Swain (1980). In these comparisons the distribution ferent distribution patterns in the 1972 fishery with of tagged smolts recaptured as one-sea-winter salmon respect to both time and area of recapture (Fig. 26). varied significantly (P < 0-001) with respect to area Tagged smolts recaptured as two-sea-winter fish were of recovery from the estimated catch distribution of recovered further north and earlier in the season than one-sea-winter salmon at West Greenland. The two- the one-sea-winter salmon recaptures. Catch sampling sea-winter recaptures did not vary significantly information presented by Munro and Swain (1980) (P > 0-05) from the estimated distribution of two- also indicates that the two-sea-winter salmon were sea-winter salmon in the fishery. Chi-square analyses caught further north than the one-sea-winter fish, for these comparisons are presented in Table 58. although they found no evidence of temporal dif­ The area distribution of tagged smolts recaptured ferences between one- and two-sea-winter salmon. as one-sea-winter salmon and originating from North 88 C. P. Ruggies and J. A. Ritter

Table 58. Contingency tables for distribution by area Table 59. Comparison of the distributions of North of recovery at West Greenland for North American American and European smolt tags by area of re­ tagged smolts recaptured as one- and two-sea- capture at West Greenland in 1972. Tag recaptures winter salmon in the 1972 fishery. Expected fre­ are comprised of one-sea-winter salmon only with quencies are based on estimated distributions of the European recaptures being from smolts from one- and two-sea-winter salmon respectively. Esti­ rivers in England, Wales and Scotland (Swain, mates derived from catch figures reported by Jensen 1980) (1980) and apportioned according to sea age as re­ C Recap Lui es ported by Munro and Swain (1980) Areas > North American European f Recap tui es Area "\ Observed Expected I 18-0 20-0 II 19-6 11-0 1-sea-winter salmon III 34-0 17-0 IV 85-4 26-0 I 18-0 29-71 V 44-7 20-0 II 19-6 15-11 VI 47-3 25-0 III 34-0 27-66 Total IV 85-4 58-86 249-0 119-0 V 44-7 91-16 X2 = 11-697 VI 47-3 26-47 d.f. = 5 Total 249-0 P < 0-05 > 0-02

X2 = 59-400 d.f. = 5 P < 0-001 and Maine (USA) groupings of smolts, respectively. 2-sea-winter salmon The Miramichi grouping included recaptures from I 9-3 11-59 both wild and hatchery-reared smolts from stocks 11 7-3 4-59 native to the Miramichi River system. The Chaleur 111 5-4 3-51 Bay grouping was comprised of recaptures from IV 5-1 5-44 hatchery-reared smolts originating from the Resti­ V 2-9 4-02 VI 1-0 1-86 gouche River and broodfish collected from Chaleur Total 31-0 Bay at New Mills, New Brunswick, and Maria, Quebec. The Maine grouping was comprised of re­ X2 = 3-801 d.f. = 5 captures from hatchery-reared smolts from stocks P < 0-70 > 0-50 native to rivers in the State of Maine. The distribution of tag recaptures for each grouping is recorded in Appendix Table III. American rivers were compared with the distribution Distributions of tag recaptures for the three group­ of European one-sea-winter recaptures reported by ings were compared statistically by the chi-square Swain (1980) for smolts emigrating from rivers in method (Tables 60 and 61). Although the groupings Scotland, England and Wales (Table 59). In this appear to have differed with respect to time and comparison the European tagged smolts were re­ location of recovery in the 1972 fishery, with one covered further north than North American tagged exception, their distributions were not statistically ones. The distributions of North American and Euro­ different (P > 0-05). The Miramichi and Maine pean smolt tags recaptured at West Greenland were groupings of smolts produced this exception (P < 0-05) significantly different (P < 0-05) with respect to area with respect to time of recovery in the fishery. The of recapture when analysed by the chi-square method. area distributions of recaptures for these same group­ These results support the findings of Lear and Sande- ings, however, were not significantly different (P > man (1980) that the proportion of salmon of North 0-05). American origin in the 1972 fishery gradually de­ creased from south to north along the west coast of Greenland. SUMMARY AND CONCLUSIONS Tag recoveries from three geographic groupings of The review of North American smolt tagging ex­ North American smolts were compared with respect periments confirms that a major portion of the rivers to time and location of recovery in the 1972 West on the Atlantic side of North America produce salmon Greenland fishery. Recaptures considered in this some of which migrate to West Greenland. Between comparison were confined to one-sea-winter salmon different river stocks considerable variation exists in originating from the Miramichi River, Chaleur Bay the rate at which they contribute to the Greenland Review of North American smolt tagging to assess the Atlantic salmon fishery off West Greenland 89

Table 60. Comparison of the distributions of smolt Table 61. Comparison of the distributions of smolt tags by time of recovery at West Greenland in 1972 tags by area of recovery at West Greenland in 1972 for one-sea-winter recaptures from groupings of for one-sea-winter recaptures from groupings of Miramichi, Chaleur Bay and Maine stocks Miramichi, Chaleur Bay and Maine stocks

~ . . . /------K ecaptures------s C------Recaptures------s, ime in erva Miramichi Chaleur Bay Maine Miramichi Chaleur Bay Maine

16 Ju l — 19 Aug 22-4 9-0 7-8 I 4-5 5-1 5-4 20 Aug— 23 Sep 37-6 28-0 42-1 II 3-4 4-1 3-0 24 S ep- 2 Dec 28-0 12-0 24-1 III 10-1 3-1 13-8 Total 88-0 49-0 74-0 IV 28-5 18-6 28-1 V 14-8 11-9 11-3 Chi-square analyses VI 26-7 6-2 12-4 Miramichi versus Chaleur Bav Total 88-0 49-0 74-0 X2 = 2-638 d.f. = 2 Chi-square analyses P < 0-30 > 0-20 Miramichi versus Chaleur Bay Miramichi versus Maine X2 = 8-588 X2 = 6-448 d.f. = 5 d.f. - 2 P < 0-20 > 0-10 P < 0-05 > 0-02 Miramichi versus Maine Chaleur Bay versus Maine X2 = 5-210 d.f. = 5 X2 = 1-980 d.f. = 2 P < 0-50 > 0-30 P < 0-50 > 0-30 Chaleur Bay versus Maine Miramichi versus Chaleur Bay versus Maine X2 = 6-139 X2 = 7-599 d.f. = 5 d.f. = 4 P < 0-30 > 0-20 P < 0-20 > 0-10 Miramichi versus Chaleur Bay versus Maine X2 = 14-103 d.f. = 10 fishery. Year-to-year variation in recapture rate at P < 0-20 > 0-10 Greenland within individual stocks is positively cor­ related with the magnitude of the Greenland fishery. During 1971, at the height of the Greenland salmon dispersed along the west coast of Greenland. It is fishery, recaptures in the West Greenland fishery of quite probable, however, that the distribution varies twelve North American stocks for which detailed data between years so that the distribution pattern in 1972 are available accounted for from 33 to 75 per cent of may not be valid another year. all tag recaptures from North American tagged smolts destined to return as two-sea-winter or older salmon. ACKNOWLEDGEMENTS Variation among stocks is influenced by sea age at first maturity, as “grilse” do not contribute to the The authors are grateful for the large amount of unpublished tagging information supplied by: Dr. Greenland fishery. Other factors related to stock origin contribute to this variation, but these are not Paul Elson, the St. Andrews Biological Station ; Mr. as important as the “grilse” factor in determining Al Meister, the Maine Atlantic Sea Run Salmon the degree to which individual North American rivers Commission; Mr. Bert Tetreault, the Quebec Depart­ produce salmon which migrate to West Greenland. ment of Tourism, Fish and Game; Mr. Gary Turner, the Halifax Resource Development Branch; Mr. Jerry Analysis of smolt recaptures with respect to time and location of their recovery in the fishery suggest Pratt, the St. John’s Resource Development Branch, without which this analysis could not have been made. that salmon of different sea ages and stocks are not randomly intermingled at West Greenland. The two- We would also like to thank Dr. Robin Harger, Halifax Resource Development Branch, for his help with the sea-winter salmon were distributed further north and statistical analysis. disappeared from the 1972 fishery earlier in the season than the one-sea-winter salmon. Similarly, North American salmon were more southern in their distri­ REFERENCES bution than the European salmon. Individual North Anon. 1967. Report of the ICES/ICNAF Joint Working Party American river stocks appear to have been unevenly on North Atlantic salmon, 1966. Coop. Res. Rep. Cons. int. distributed in the Greenland fishery, although widely Explor. Mer, Ser. A, No. 8, 27 pp. 90 C. P. Ruggies and J. A. Ritter

Anon. 1969. Second report of the ICES/ICNAF Joint Working and discriminant functions for identifying continental origin Party on North Atlantic salmon, 1969. Ibid., Ser. A, No. 12, of Atlantic salmon. This volume, p. 68. 18 pp. Munro, W. R. and Swain, A. 1980. Age, weight and length Anon. 1971. Third report of the ICES/ICNAF Joint Working distributions and sex ratio of salmon caught off West Greenland. Party on N orth Atlantic salmon, 1970. Ibid., Ser. A, No. 24, This volume, p. 43. 33 pp. Pyefinch, K. A. 1969. The Greenland salmon fishery. Proceedings Anon. 1973. Fourth report of the ICES/ICNAF Joint Working of the Challenger Society, IV: 4—12. Party on North Adantic salmon. Ibid., No. 35, 37 pp. Ritter, J. A. 1972. Salmon hatchery evaluation in the maritime Horsted, Sv. Aa. 1971. On the interrelationship between some provinces - results of smolt tagging in 1968. Environment parameters used for assessing the effects of the West Greenland Canada, Resource Development Branch, Halifax, Nova Scotia salmon fishery. Int. Comm. NW Atlant. Fish., Res. Doc. 71 /72. Progress Report No. 5, 22 pp. (Also ICES/ICNAF Salmon Doc. 71/16.) Saunders, R. L., Kerswill, C.J. and Elson, P. F. 1965. Canadian Jensen, J. M. 1980. Recaptures of salmon at West Greenland Atlantic salmon recaptured near Greenland. J. Fish. Res. Bd tagged as smolts outside Greenland waters. This volume, p. 114. Can., 22: 625-9. Kerswill, C.J. and Keenleyside, M. H. A. 1961. Canadian Swain, A. 1980. Tagging of salmon smolts in European rivers salmon caught off Greenland. Nature, 192: 279. with special reference to recaptures off West Greenland in Lear, W. H. and Sandeman, E. J. 1980. Use of scale characters 1972 and earlier years. This volume, p. 93.

APPENDIX Appendix Table 1. Summary of recaptures (grilse excluded) for 47 selected groups of wild and hatchery-reared smolts tagged and released in North American rivers from 1959 to 1971. Under recaptures designated as “home”, numbers in parentheses are estimates of unreported tags returning to the home river and are not included in “home” or “total” recapture figures. All grilse returns are excluded including those one-sea- winter recaptures in distant fisheries that were destined to mature as grilse. The numbers of potential grilse recaptures in distant fisheries were estimated considering location and time of capture

Year of No. f — Recaptures (grilse excluded)— ^ release Stock origin released Greenland Other Home Total

1969 Wild, Sandhill R., Labrador, Nfld. 6 741 6 36 7 ( 0)i 49 1970 8 014 48 51 9 ( O)1 108 1971 10 320 7 28 10 ( O)1 45

1968 Hatchery, New Mills (Chaleur Bay) in 5 000 13 24 16 ( 2)2 53 SW Miramichi R., N.B. 1969 10 000 40 32 13 (12)2 85 1967 Hatchery, Restigouche in Restigouche R., 5 000 2 8 10 ( 2)3 22 N.B.

1968 Hatchery, Restigouche in SW Miramichi R., 6 996 25 44 30 (10)2 99 N.B.

1969 Hatchery, Restigouche, 11061 in 19 561 76 91 33 ( 9)1.2 200 NW Miramichi R., 8500 in SW Miramichi R., N.B.

1959 Wild, Miramichi R., estuary, N.B. 3 442 1 7 31 ( 8)2 39 1968 3 491 16 22 40 ( 7)2 78 1969 8 684 33 60 27 ( l)2 120 1970 6 835 54 21 15 (23)2 90 1971 10 234 26 24 7 (17)2 57

1962 Wild, NW Miramichi R., N.B. 5611 2 13 39 ( 0)1 54 1963 4 561 9 3 12 ( 0)1 24 1964 12 834 9 17 58 ( 0)1 84 1965 15 361 73 25 166 ( 0)1 264 1966 8 450 25 55 61 ( 0)1 141 1967 11 299 17 30 97 ( 0)1 144 1968 28 043 110 65 261 ( 0)1 436 1969 8916 40 32 38 ( 0)1 110 1970 11 722 62 28 56 ( 0)1 146 1971 11 417 65 45 46 ( 0)1 156 Cont’d Review of North American smolt tagging to assess the Atlantic salmon fishery off" West Greenland 91

Appendix Table 1 cont’d

Year of No. f— Recaptures (grilse excluded)— s, release Stock origin released Greenland Other Home Total

1965 Hatchery, Miramichi early run in 10 020 34 57 53 ( 0)1 144 NW Miramichi R., N.B. 1966 13 802 10 30 58 ( 0)1 98 1967 15517 6 17 54 ( 0)1 77

1965 Hatchery, Miramichi late run in 4 797 10 21 32 ( 0)1 63 NW Miramichi R., IN .B. 1966 18 295 47 89 97 ( 0)1 233 1967 14 440 9 36 45 ( 0)1 90

1968 Hatchery, Miramichi late run, 8074 in 14 826 39 68 76 ( 7)M 183 NW Miramichi R., 6752 in SW Miramichi R., N.B.

1969 Hatchery, Miramichi late run in 9 800 10 28 3 ( 2)4 41 SW Miramichi R., N.B. 1971 6 344 7 8 4 (16)4 19

1968 Hatchery, River Philip in River Philip, N.S. 4 983 44 18 16 ( 0)1 78 1969 4 949 24 23 1 ( 2)» 48 1970 19 988 18 5 0 ( 1)* 23

1968 Wild, Margaree R., N.S. 2 185 6 12 2 ( 4)4 20 1971 Hatchery, Medway, 9793 in Medway R., 14 685 13 2 8 ( 8)2 23 4892 in LaHave R., N.S.

1967 Hatchery, Saint John in Saint John R., N.B. 19 931 1 13 12 ( 0)1 26 1969 17 959 6 10 14( 0)1 30 1970 46 564 10 2 21 ( 0)1 33 1971 46 283 17 5 135 ( 0)1 157

1966 Hatchery, Maine in Maine rivers, USA 80 015 40 84 163« ( 0)1 187 1968 24 195 3 2 136 ( 0)1 18 1969 74 530 65 44 64« ( 0)1 173 1970 47 835 404 65 2616 ( 0)1 730 1971 29 900 87 21 163* ( 0)1 271

1 Fence or trap count is included with home recaptures and assumed to be complete. 2 Estimate of unreported tags is equal to three times the number of bright multi-sea-winter salmon angled minus those recaptured as kelts or black salmon. This is based on the assumption that the sport fishery harvests 25 per cent of those fish entering fresh water. 3 Arbitrary estimate made necessary because of no recaptures in fresh water. 4 Estimate of unreported tags is equal to four times the number of bright multi-sea-winter salmon angled minus those recaptured as kelts or black salmon. This is based on the assumption that the sport fishery harvests 20 per cent of those fish entering fresh water. 5 Estimate of unreported tags taken by poachers. 8 Because the actual breakdown of numbers of grilse and multi-sea-winter salmon in home waters was not available but estimated to be 5 per cent, home-water recaptures have been adjusted accordingly. 92 C. P. Ruggles and J. A. Ritter

Appendix Table 2. Distribution in the 1972 Greenland Fishery of North American smolt tags recaptured as one-sea-winter and two-sea-winter salmon, respectively. Greenland catch figures represent numbers of salmon and are from Jensen (1980)

Date Recaptures r Area (week No.) or catch i II III IV V VI Total

Ju l 1 6 - Recaptures Aug 19 1 sea winter 1-0 2-4 11-1 4-2 18-1 6-4 43-2 2 sea winters 2-1 3-3 5-3 3-1 1-7 1-0 16-5 (30-34) Catch 444 13 404 49 319 3 865 94 957 8 260 170 249 Aug 20 - Recaptures Sep 23 1 sea winter 11-4 12-2 14-3 46-2 17-0 29-6 130-7 2 sea winters 6-2 3-0 0-1 0 0-2 0 9-5 (35-39) Catch 58 715 20 095 13 889 92 961 89 961 40 726 316 347 Sep 24 - Recaptures Oct 28 1 sea winter 5-6 5-0 8-6 31-0 9-6 11-3 71-1 2 sea winters 1-0 1-0 0 2-0 1-0 0 5-0 (40-44) Catch 17 639 4 592 2 545 35 456 21 125 11 120 92 477 Oct 29 - Recaptures Dec 2 1 sea winter 0 0 0 4-0 0 0 4-0 2 sea winters 0 0 0 0 0 0 0 (45-49) Catch 1 144 212 5 3 667 175 355 5 558 Recaptures Total 1 sea winter 18-0 19-6 34-0 85-4 44-7 47-3 249-0 2 sea winters 9-3 7-3 5-4 5-1 2-9 1-0 31-0 Catch 77 942 38 303 65 758 135 949 206 218 60 461 584 631

Appendix Table 3. Distribution in the 1972 Greenland fishery of tag recaptures originating from the Miramichi River, Chaleur Bay and Maine (USA) groupings of smolts, respectively. Recaptures are one-sea-winter salmon only

Date f------A re a ------^ (week No.) Recaptures IIIIIIIV VVI Total

Ju l 16 - Miramichi 0 0-4 4-6 3-2 9-8 4-4 22-4 Aug 19 Chaleur Bay 0 1-0 1-0 1-0 4-0 2-0 9-0 Maine 1-0 0 3-5 0 3-3 0 7-8 (30-34)

Aug 20 — Miramichi 2-2 3-0 2-3 15-8 2-3 12-0 37-6 Sep 23 Chaleur Bay 5-1 3-1 2-1 9-3 4-2 4-2 28-0 Maine 1-1 3-0 5-9 14-9 5-8 11-4 42-1 (35-39)

Sep 2 4 - Miramichi 2-3 0 3-2 9-5 2-7 10-3 28-0 Oct 28 Chaleur Bay 0 0 0 8-3 3-7 0 12-0 Maine 3-3 0 4-4 12-2 2-2 1-0 23-1 (40-44)

Oct 29 - Miramichi 0 0 0 0 0 0 0 Dec 2 Chaleur Bay 0 0 0 0 0 0 0 Maine 0 0 0 1-0 0 0 1-0 (45-49) Miramichi 4-5 3-4 10-1 28-5 14-8 26-7 88-0 Total Chaleur Bay 5-1 4-1 3-1 18-6 11-9 6-2 49-0 Maine 5-4 3-0 13-8 28-1 11-3 12-4 74-0