Atlantic Salmon Maritimes Region Overview
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Fisheries Pêches and Oceans et Océans DFO Science Maritimes Region Stock Status Report D3-14 Maritimes Region Salmon Fishing Areas Atlantic Salmon 15 Maritimes Region 16 Overview 17 23 18 19 Background 22 20 There are nine Atlantic salmon (Salmo salar) management areas known as Salmon Fishing Areas (SFA) in the Maritimes Region of eastern Canada. There are more than 150 rivers 21 within the Maritimes for which Atlantic salmon catches have been reported. Each river is assumed to consist of at least one stock with the larger rivers containing several stocks. There is a diverse life history structure including variations in freshwater residence time, age at maturity and the extent of ocean migrations. Spawning populations consist of varying The Fishery proportions of small salmon (fork length <63 cm) and large salmon (fork length 63 cm). In the majority of rivers, small salmon are predominantly maiden fish (never spawned Atlantic salmon were harvested by two user before) which have spent one year at sea before returning to groups: Aboriginal communities and spawn (one-sea-winter salmon). The large salmon component contains a mixture of maiden fish which have spent two and recreational fishers. Aboriginal communities occasionally three years at sea before spawning and previous were given first access to salmon (after spawners which are returning for a second or subsequent conservation requirements) based on spawning. The majority of the large salmon maiden spawners are female. The relative proportions of the size groups in the communal needs for food, social and returns vary geographically Conservation for Atlantic salmon ceremonial purposes. Aboriginal fisheries is considered to be a threshold reference point. The consequences of egg depositions below conservation to the occurred throughout the Maritimes Region long-term sustainability of the stock are unknown but the in accordance with agreements and likelihood of deleterious effects are greater when egg communal fishing licenses. Several depositions are below conservation. The conservation requirements are established for individual rivers based on Aboriginal communities chose not to 2.4 eggs per m2 of river habitat. In rivers impacted by exercise their right to the communal airborne acid depositions, the conservation requirements are under review. allocations because of conservation considerations. The status of the stocks is assessed on the basis of the proportion of the conservation egg deposition achieved in a given year and the trends in abundance of various life stages. Recreational fisheries management in 1996 consisted of three strategies: 1) regular retention fisheries for small salmon with mandatory hook-and-release for large salmon, 2) hook-and-release of all salmon April 1997 Maritimes Region Atlantic Salmon Maritimes Region Overview regardless of size reflecting reduced stock Harvests (by all users) in 1996 were levels, and 3) complete closure reflecting unchanged or declined relative to harvests depressed stock levels. A large proportion since 1984. Reduced harvests in 1996 were of the rivers in Nova Scotia was closed to a consequence of the more restrictive angling or was under hook-and-release management regime as well as declines in management in 1996. abundance of salmon in the Maritimes Region. Harvests increased in only one assessed river, River Philip on the Recreational Fisheries Management in 1996 Northumberland Strait shore of Nova Scotia Open for retention of small salmon (Table 1). Hook-and-release all salmon Closed to salmon fisheries Québec Resource Status Information was presented for 47 Atlantic salmon rivers of the Maritimes Region. Returns and spawning escapements of Atlantic salmon in 1996 were assessed for 38 U.S.A. of these rivers (Table 1). Escapements are the differences between returns and total removals (including Aboriginal community harvests, angling harvest, mortalities associated with hook-and-release angling of 3% to 10% of the released catch depending upon the river, and broodstock collections). Other management measures in effect in Egg depositions were estimated from the 1996 which potentially affected the salmon biological characteristics of the adults. In stocks from the Maritimes Region include numerous rivers, hatchery progeny were the fifth year of the commercial salmon identified on the basis of marks (generally a moratorium for insular Newfoundland and clipped adipose fin), fin deformities, and the re-initiation of the Greenland fishery in scale characteristics. Aquaculture escapees August of 1995 which would have were identified on the basis of body intercepted salmon destined to return to the morphology, fin deformities and scale Maritimes Region as large salmon in 1996. characteristics. In those areas where retention angling Various techniques were used to assess the fisheries or hook-and-release fisheries were returns and spawning escapement to in effect, the impression from anglers was of individual rivers: 10 rivers using angling high abundance of salmon in 1996. End-of- catches and assumed exploitation rates season assessments of returns indicated that (Ang), one river based on broodstock seining throughout the Maritimes, good angling success rate (Br), one river using a catch rate opportunities were the result of water index (CR), four rivers using counting fences conditions and generally early arrival of (Fe), nine rivers using counts at fishways salmon into the rivers. These conditions (Fw), five rivers using mark and recapture promoted the distribution and availability of experiments (MR), one river using a relative fish to anglers early in the year. index from a neighbouring assessed river 2 Maritimes Region Atlantic Salmon Maritimes Region Overview (Rel), one river using shore counts (Sh), one coast of Nova Scotia (NS) were composed river using snorkel counts (Vi) and five of varying proportions of wild and hatchery rivers using snorkel counts with a mark and origin fish. All the returns to five acid- recapture calibration (ViM). impacted rivers of NS were hatchery origin. Aquaculture escapees were observed in Origin of Returns significant proportions in two rivers of the Fish of hatchery origin made up varying outer Bay of Fundy, New Brunswick (NB); proportions of the returns to rivers. Wild these rivers are in close proximity to the salmon (defined as returns from eggs aquaculture production centre. Escapees spawned naturally in the gravel) represented were also observed in the Saint John River at more than 95% of the returns in most of the Mactaquac (Index 45), Annapolis River rivers from the southern Gulf of St. (outer Bay of Fundy, NS, Index 38), and in Lawrence with the exception of rivers in Middle River (Bras d’Or Lake, Cape Breton, Prince Edward Island (PEI) where hatchery NS, Index 23). origin fish comprised more than 90% of the returns. Returns to rivers of the Atlantic Aquaculture Wild Hatchery 1 2 Aquaculture escapees present 5 3 4 6 7 10 20 8 21 44 9 45 41 11 12 14 22 42 17 19 23 15 13 16 18 24 47 46 43 40 39 25 26 38 27 30 32 31 29 37 33 28 34 35 36 3 Maritimes Region Atlantic Salmon Maritimes Region Overview Escapements relative to conservation Atlantic coast of NS met or exceeded the Egg depositions relative to the conservation conservation requirements whereas 10% of requirements were met or exceeded in 15 of the ten rivers of the Bay of Fundy met or the 38 rivers (39%) assessed in 1996. exceeded conservation (Table 1). Six of the Conservation requirements were met or 10 Bay of Fundy rivers had escapements exceeded in 11 of 18 rivers (61%) assessed which were estimated to have been less than in the southern Gulf of St. Lawrence. Only 25% of conservation requirements. 30% of the ten rivers assessed for the 1 2 Uncertain but < 25% 5 3 4 6 7 20 8 10 21 44 9 45 41 11 22 42 19 13 23 46 24 47 43 17 40 39 26 25 38 30 27 29 32 Egg deposition (black) as the proportion of the conservation requirement 4 Maritimes Region Atlantic Salmon Maritimes Region Overview Trends in returns and escapements in the late 1970’s. Increased return rates in Returns and escapements in 1996 were 1996 from hatchery smolts were also generally improved from 1995 throughout observed in the Liscomb River and LaHave the Maritimes Region. Declines relative to River. 1995 were observed in the Jacquet River (Index 4; SFA 15), Miramichi and 5 Buctouche rivers (Index 6 to 8; SFA 16), and the Salmon River (Index 25; SFA 20). 4 3 Status in 1996 relative to 1995 2 Increase No change 1 Return rate / Taux de retour (%) Decline 0 1974 1978 1982 1986 1990 1994 Year / Année 5 1SW Salmon / Unibermarin MSW Salmon / Pluribermarin 3 4 6 Smolt return rate (by year of smolt stocking) to 1SW 7 and MSW salmon returns to the Mactaquac facility 10 20 8 21 of the Saint John River. 44 9 45 41 12 18 11 15 19 22 42 23 14 17 47 46 13 16 24 General abundance of adult salmon 26 25 In none of the rivers in the Maritimes Region 29 27 was the abundance of wild salmon 32 considered to be high relative to historical or expected levels of production. Wild salmon in the rivers of the southern Gulf of St. Lawrence (SFA 15, 16 and 18) There were significant declines in status are considered to be at medium levels of (annual returns and escapements) since 1984 abundance whereas their levels in Atlantic in all SFAs with the exception of the coast and Bay of Fundy rivers are currently Northumberland Strait rivers of Nova Scotia low. As well, in all the rivers with (SFA 18) where the status was generally appropriate time series of abundance values, unchanged (Table 1). The status of the the annual trend in abundance of wild salmon Miramichi River has improved since 1984 since 1984 is consistently downward or but in the last five years, returns have unchanged.