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The Atlantic Salmon 2 Underwater World

tlantic salmon are widely known and A highly esteemed for their beauty of form, their intrepid spirit, and their match­ THE less qualities as game and food fish. Related, but distinct from salmons of Pacific waters, the species (Sa/mo sa/ar), or ''salmon the ATLANTIC leaper", ranges the North Atlantic from (} native streams on both sides of the ocean. SALMON Known and valued in Europe since Ro­ man times, Atlantic salmon were a valuable

food source for North American natives, HUDSON and became an important commodity of SAY trade for European settlers in the New World. According to the accounts of most writers, salmon were so numerous that their eternal abundance was taken for granted until recent years, when pressures of overfishing, pollution and obstruction of freshwater habitat resulted in serious depletion of stocks. Current fishery management efforts are directed toward rehabilitation of salmon populations to ensure conservation and prudent use of this valued resource. Atlantic Salmon Distribution Description 0 Present & Aboriginal The Atlantic salmon has an elongate, - Aboriginal Only somewhat laterally compressed body, with a relatively large mouth, fairly large scales, and a fleshy adipose fin on the back just in just prior to its first migration to the se~. front of the tail fin. Mature salmon general­ parr colouration becomes masked by a ly weigh between two and 10 kg, but covering of silvery mucus. occasionally exceed 15 kg . In the sea, the adult is silvery on the Coloration of the Atlantic salmon varies sides, white on the undersurface and varies greatly with age or life stage, and to some through shades of brown, green or blue­ degree with environment. The small juve­ gray on the back. The adult also has nile, or parr, has 8 to 11 dark, pigmented, numerous x-shaped black spots, primarily vertical bars or parr marks along each side. above the lateral line, scattered along the Between each of these, along the lateral body and on the head. After reentering line, is a single red spot. The back is gray to fresh water to spawn, the adult loses much brown with dark spots, and the ventral sur­ of its silvery colour and, as the spawning face shades to a silvery white or light yel­ season approaches, becomes bronze to dark Fig. I Salmon preparing to spawn. low. As the fish reaches the smolt stage, brown, with reddish blotches along the sides.

Distribution The present range of the Atlantic salmon includes most of the North Atlantic Ocean and a large percentage of its accessible rivers and streams. In the eastern Atlantic, it is found from above the Arctic Circle south to Portugal, including the Scandina­ vian countries, the White Sea area of north­ western Russia, the Baltic, Britain md Ireland. It also occurs in Iceland ;md southern Greenland. In the northwest Atlantic, the salmon ranges from Ungava Bay in northern Quebec, to a few rivers in the northeaster United States. Distribution in Canada Underwater World 3

eludes many rivers and streams of New lbeen at sea two to three years before first Brunswick, Newfoundland and Labrador, returning to spawn, normally weigh 4 to Quebec, Nova Scotia and a few streams in 14 kg and average 5 kg in Canadian waters. Prince Edward Island. Surviving natural As the male salmon approaches sexual populations in the United States are maturity prior to spawning, a marked confined to a small number of streams in change in its external appearance becomes Maine. Rehabilitation efforts in recent evident. Its head becomes elongated and its years, however, have resulted in the reintro­ lower jaw is enlarged and forms a pro­ duction of the species to some other New nounced hook, or kype, at its tip. England rivers. The actual nesting or spawning site is selected by the female. It is normally a Life History and Migration clean, well-aerated, gravel-bottomed riffle The Atlantic salmon has been referred to area. Still water and stream bottoms of Fig. 2 Head of female spawning salmon. as the classic anadromous fish. An anadro­ mud, silt or sand are avoided, since water mous fish is one which migrates from the circulation may be inadequate and eggs can sea into the rivers to spawn. In Canada, easily become smothered. spawning runs of Atlantic salmon normally While the male keeps watch to fend off enter the rivers between May and Novem­ intruders, excavation of the spawning nest ber, although some runs begin as early as or redd - a simple depression in the gravel March or April. Spawning runs consist of ·- is carried out by the female. She accom­ varying proportions of grilse (salmon that plishes this by rapid thrusts of her tail, have spent one year at sea) and older deepening and shaping the nest, 'as the salmon (two or more sea-years). The ratios flowing water helps carry away the dis­ vary from river to river, from season to sea­ placed gravel. Once the nest is prepared, the son and throughout any given season. Some male and female align themselves above it. rivers are known as either predominantly Eggs and sperm - milt - are then released grilse or older salmon producers. simultaneously and the fertilized eggs are 3 Head of male spawning salmon. Although adult fish enter rivers from covered with gravel by the female. In some early spring to late fall, actual spawning instances, a pair of salmon may utilize usually occurs in October and November. several redds before spawning is complete. In northern regions, such as Ungava and Egg production varies directly with fish northern Labrador, spawning is common in size, averaging 1,500 to 1,800 eggs per early October; in more southerly regions, kilogram ot temale weight. most spawning occurs from late October to Although the adults of other salmon late November. species die shortly after spawning, the Depending on the time of entry to a river, Atlantic salmon normally survives the salmon are loosely classified as early-run or initial stress of at least one spawning. They late-run fish. In either case, salmon are are then known as kelts, slinks or black more likely to be observed entering a river salmon. These fish return to the sea, some during and immediately following a freshet, immediately after spawning, and others the when there is an increased volume of clean, following spring. By this time they have cool water. The grilse, having spent one been in fresh water without feeding from a Fig. 4 Newly hatched salmon with attached yolk winter at sea, normally weigh 1.5 to 2.0 kg. few months ·to almost one year. After sac. Older salmon (maiden salmon), which have reconditioning at sea, some will return to freshwater to spawn at least one more time. Others may spawn three or four times in subsequent seasons. Salmon eggs are 5 to 7 mm in diameter, are pale orange or amber in colour and are slightly adhesive for a short time after r,elease. Under the fluctuating temperature conditions found in natural redds, eggs incubate over the winter months in the stream beds and usually hatch in April. Rate of development is closely related to water temperature. In hatcheries at a con­ trolled temperature of 3.9°C, hatching will occur in about 110 days. This advanced timing is important in allowing earlier f~eding during artificial rearing.

Growth Newly-hatched salmon (alevins) are about 15 mm in length and carry a large 4 Underwater World

Growth is slow in the freshwater environ­ ment where parr usually spend from two to three years before reaching the smolt stage and migrating downstream to sea, where their growth rate increases due to physio­ logical changes and a greater abundance of food. Smolts normally average 125 to 150 mm in length, but in more northerly areas smoltification does not usually occur until the fish are older and larger, for example, four to eight years of age and a minimum length of about 180 mm in Ungava. Marine feeding areas for young salmon cover a wide scope. For example, it appears that certain New Brunswick salmon do not venture beyond the waters of the Bay of Fundy, while others travel long distances in ~ '' search of food, many to the coastal waters of Newfoundland, Labrador and West -..~ - · Greenland. Much is still to be learned of - · marine feeding areas and migration routes. -- ""'-'~"-~...;.:.~-~~ It is only recently that scientists have Fig. 5 Young salmon. yolk sac which nourishes them for the first gained detailed knowledge of the food of few weeks while they are still buried in the salmon in the sea. In the last decade, it has gravel. By the time they emerge from the been found that smolt and larger salmon gravel in late May, the yolk sac has been are voracious eaters and will feed o absorbed, and the young fish, now called anything they find within their ran parr, are free-swimming and begin active Fishes, including herring, capelin, alewiv, feeding. launce, small mackerel and smelt, and crus­ Parr usually lay claim to their own terri­ taceans such as shrimp, squid, amphipods tory, which varies from one to several and euphausiids are taken when the square metres, depending on the size of the opportunity arises. fish. They prefer an area where the water Salmon are strong swimmers and because flow is rapid and the bottom gravelly or they are relatively large are able to with­ stony. stand predation better than some other fish . While in fresh water, young parr feed Their chief danger comes from the larger principally on the larvae of aquatic insects. fish such as tuna, sharks, swordfish and As they become older, they also consume even cod and pollock. Seals take salmon larger larvae and insects which fall into the from nets, but it is not known whether they water. In turn, they are preyed upon by are able to catch free-swimming salmon. fish-eating birds such as mergansers and Salmon are known to wander extensively Fig. 6 Salmon parr. kingfishers and predacious fish such as eels. at sea, but most of them return to the stream or river where they were spawned. Some instances of recapture of tagged fish in other than their home streams are exceptions to this rule. Until now, ocean pollution does not appear to have affected salmon. However, pollution in rivers and estuaries has been detrimental, sometimes concealing the sen­ sitive identification of home-stream water thus preventing the salmon from going up~ stream to spawn. Acid rain has also begun seriously to affect the Atlantic salmon's freshwater habitat and is now considered one of the more serious threats to its future. Damming of rivers has affected the repro­ ductive cycle by barring salmon from so spawning reaches and by flooding spawn and rearing areas. Also, dam headpo1. sometimes become deoxygenated, hin­ dering upstream migration. Underwater World 5

Landlocked Salmon In eastern North America, Atlantic salmon occur naturally as landlocked races, or "ouananiche' ', in some rivers and lakes in Newfoundland and Labrador, Quebec, Nova Scotia, New Brunswick and fy1aine . They have also been successfully established in lakes in Ontario, New Hampshire, Ver­ mont and New York. In Europe they occur naturally in Norway, Sweden, U.S.S.R. , and one population in Dalmatia, south­ western Yugoslavia. In both North America and Europe, landlocked salmon may exist in either nor­

.Ill mal or dwarf forms. Fork lengths of dwarf populations in eastern Newfoundland sel­ ' dom exceed 150 mm and weights seldom exceed 40 g. Lengths of normal-size individ­ uals throughout their distribution generally range from 200 to 600 mm, with weights at times exceeding 6 kg. Ouananiche attain their largest size and reach maximum age when forage species·, particularly landlocked smelt, are present. Their most important source of food is aquatic insects. Ouananiche are migratory fish during certain well-defined periods of their lives: they move either up or down a drainage area from one body of water to another, either to spawn (adults) or to reach more favourable feeding areas (primarily juven­ iles). Unlike their anadromous cousins, ouananiches often spawn around the shores Fig. 7 Sport fishing on an Atlantic river. of lakes. Sport fishing for landlocked salmon is normally done by fly fishing with rod and reel, or by trolling. They are also taken Fig. 8 Drawing of salmon scale indicating its life history. through the ice during the winter fishing season.

Egg s la id in gravel. October. 1963 Harvesting the Salmon Resource The Atlantic salmon is fished commer­ cially, recreationally, and by natives for food. Commercial fishing is permitted only in tidal waters and fishing gear commonly used includes trapnets or gillnets fastened near shore. There were substantial driftnet fisheries in the open sea off Port-aux­ Basques in southwest Newfoundland and off the Miramichi and Saint John rivers in Becomes a smelt at end of ------+----+---~ New Brunswick but, for conservation pur­ second year. sp ring of 1966. and goes to sea poses, these were banned in 1972, along with all commercial salmon fishing in New Brunswick and the Gaspe Peninsula of Quebec. The commercial fishery in New Spawned in fall of 196 7 plus ------t-'...------"- Brunswick was reopened in 1981 on a limit­ 1967-68 wi nt er ed basis, as some stocks had recovered to a commercially-exploitable level. Catch and effort data are collected regularly to help determine the status of stocks from each area and to identify optimum harvest levels. 6 Underwater World

Not all salmon angling waters are open to the public. In New Brunswick and Quebec many of the best angling waters are in private hands; others are controlled by T - BarTag provincial governments. Some of the latter areas are leased to private individuals; others are made available to individual resident anglers on a limited basis. In Nova

DEPT. OF FISHERIES Small Carlin Tag Large Carlin Tag Scotia and Newfoundland all rivers are BOX 550 0 open to the public; in Prince Edward Island ~ (For Smolts) HALIFAX. N. S. (For Adults) ' there are fewer opportunities to angle for salmon. All anglers require a provincially­ issued licence to fish for salmon, even those fishing private waters. There are approximately 6,000 licensed Total Canadian sport catches of Atlantic commercial salmon fishermen in Atlantic salmon have ranged in recent years from Canada. In some communities they depend approximately 80,000 to 130,000 fish, on the salmon fishery for more than 50 per weighing between about 240 t and 400 t. cent of their (:lnnual incomes. Recent annual The economic value of the salmon sport landings have averaged 1,800 metric tons (t) fisheries is not easily assessed. Each year in with landed values ranging from about $4 Canada, large sums of money are spent for to $6 million. The coastal, set-net fishery the purchase and maintenance of fishing off Newfoundland and Labrador has ac­ privileges, for the operation of fishing counted for about 90 per cent of this catch. lodges, for guide and caretaker services, for Atantic salmon command a higher price licences, gear and travel. on the food market than most other fish. Economists generally agree that, because They are marketed fresh, frozen, or anglers often spend a lot of money for their smoked, but seldom canned. fishing, a salmon caught by angling has a Sport fishermen have long looked upon higher value than a similar fish taken in the Atlantic salmon as king among sport fish . commercial fishery. They estimate the value Anglers fishing freshwater streams for of a rod-caught salmon is at least 3 to 20 returning grilse and salmon use rod and times the value of one taken commercially. line, and by law in Canada must use only Native food fisheries are pl,lrsued under unweighted artificial flies. Most rivers of permit by Indians and Inuit of Quebec, the Canadian Atlantic seabord have salmon New Brunswick, Newfoundland and Labra­ populations and can provide some angling. dor. In the southern areas, these fisheries are primarily conducted in the Saint John, Fig. 9 A1/a111ic Sa/111011 Research /11s1i1L11e, Miramichi, Restigouche and Richibucto S1. Andrews, NB. rivers. In the north, food fisheries are car­ ried on mainly in rivers flowing into Ungava Bay. The natives of Labrador generally do not fish in the rivers for salmon; they do, however, fish commercial­ ly in coastal waters. There is also a native commerical fishery in Quebec. Landing data for the native food fisheries are some­ what obscure and only varying estimates can be obtained. Food fishery catches are legally restricted to domestic use.

Research and Resource Management In the Maritimes and in Newfoundland and Labrador, responsibility for research and management of the Atlantic salmon lies with the federal Department of Fisheries and Oceans. Provincial government depart­ ments engage in certain related activities, including licensing of sport fishermen, assisting in law enforcement and conduct­ ing surveys and management projects. Research, either independently or under government contract, is also carried out by Underwater World 7

Scale interpretation and biochemical analyses have also been used successfully in determining stock identities and composi­ tions. For example, the North American component of salmon harvested in the West Greenland fi shery has been more accurately defined. This has enabled the assessment of effects on home-water stocks and fisheries, and has facilitated predictions of what may happen if there are changes in the West Greenland fishing strategy. In addition to research and management activities, other studies being carried on in­ clude kelt reconditioning trials in the Mari­ times; this involves articifical feeding of kelts in captivity, to assure more rapid re­ covery and a higher number of repeat spawnings than is likely to occur in nature. Other studies have included the natural rearing of parr in ponds in Newfoundland, to assure higher survival ·rates at the smolt stage, and experiments to study methods of raising salmon in marine enclosures, safe from the perils of the open sea. Responsibility for research and manage­ ment in Quebec lies with the provincial Department of Recreation, Fish and Game. <;'ig. 10 Rearing cages used in commercial universities and other agencies, such as the This department performs basic manage­ Atlantic salmon aquaculture. Atlantic Salmon Research Institute near ment, development and enhancement func­ St. Andrews, New Brunswick, and the tions, while most biological research is per­ Marine Sciences Research Laboratory near formed by Quebec universities and other St. John's, Newfoundland. provincial government and private agencies. Research activity includes laboratory Atlantic salmon management programs studies on disease, nutrition and the effects are developed in all regions in an effort to of sublethal concentrations of various maintain and enhance existing stocks. chemicals on fish health and behaviour. These programs have included measures to Genetic research and selective breeding control and limit the levels of harvesting, to studies are also being carried out in an improve the quality of, and access to, the attempt to develop stocks capable of adapt­ freshwater environment, to reduce poach­ ing to a variety of river environments. ing and to limit by-catch of salmon in other A vast amount of information and fisheries. knowledge is required to manage salmon Regulations are designed to control ex­ stocks successfully. It is necessary to know ploitation in sport and commercial fish­ the number of salmon that can be produced eries. Such regulations include those per­ in each stream, the number of spawners taining to closed seasons, control of fis hing required for this production, the locations, gear specifications (amounts, movements of the adults at sea, and their type, mesh size) and catch limitations (bag survival rates. It is equally important to limits, minimum sizes, catch quotas). Also know when and where each stock is included are the reopening of the commer­ harvested, how many fish are caught, and cial fishery in New Brunswick on a limited how much effort is required to catch these basis and the provision of federal funds for fish. Operation of fish counting traps and a "buy-back" program to permanently sample electro-fishing provide much of this reduce the harvesting pressure. information. Tagging and tag recovery Other aspects of salmon management in­ projects provide additional information on clude hatchery rearing and stocking, con­ population densities, migration routes and struction and operation of spawning timing. Tagging also serves to identify and channels and stream-side incubators, adult quantify the composition of stocks contri­ stock transfers, fishway construction, buting to specific fisheries . stream clearance, allocation of stocks in home waters and pollution control. Salmon by-catches in other commercial fisheries and poaching have placed increased pressure on rnlmon stocks. The by-catch or incidental taking of salmon bi}' 8 Underwater World

gear licensed and set for other species has Scott, W.B. and E.J. Crossman. 1973. been, at times, underevaluated. There is Freshwater fishes of Canada. Bull. evidence to indicate that the incidental No. 184, Fish. Res. Bd. of Canada. catch in recent years may have increased considerably, with a large proportion being directed or intentional. Fishery resource Text: managers are actively working to reduce K.E.H. Smith this incidental catch, as well as the Freshwater and Anadromous Division incidence of poaching. Fisheries Research Branch Actual quantities or proportions of total Department of Fisheries and Oceans resource use which can be attributed to Halifax, Nova Scotia poaching are unknown. As with the legal B3J 2S7 by-catch, poaching may have been under­ evaluated in the past. In recent years, the Underwater World factsheets are brief rela.tive scarcity of salmon from legal illustrated accounts of fisheries resources sources has made poaching even more and marine phenomena prepared for public attractive and the risks more profitable to information and education. They describe the illegal fisherman. the life history, geographic distribution, Protection of stocks by federal conser­ utilization and population status of fish, vation and protection officers and shellfish and other living marine resources, provincial wardens plays an important part and I or the nature, origin and impact of in the successful management of this marin·e processes and phenomena. valuable resource. Published by: Further Reading: Anderson, Gary J. and Ann E. Brimer. Communications Directorate 1976. Safar: The story of the Atlantic sal­ Department of Fisheries and Oceans mon. The Atlantic Salmon Association, Ottawa, Ontario the International Atlantic Salmon KIA OE6 Foundation. DF0/4120 UW/19 Dunfield, R. W. The Atlantic salmon in the history of North America. (in press) ©Minister of Supply and Services Leim, A.H. and W.B. Scott. 1966. Fishes Canada 1988 of the Atlantic coast of Canada. Bulletin Cat. No. Fs 41-33/19-1988E No. 155, Fisheries Research Board of ISBN 0-662-16507-1 Canada. Egalement disponible en fram;ais Netboy, Anthony. 1968. The Atlantic Sal­ mon, a vanishing species? Faber and Faber, London.

Netboy, Anthony. 1974. The salmon, their fight for survival. Houghton, Mifflin Co., Boston.

Others in the series Alewife Atlantic Snow Crab Lumptish Selected Freshwater Fish American Eel Bluefin Tuna Marine Fish Eggs and Larvae Selected Shrimps of British American Plaice Capel in Northern Shrimp Columbia American Shad Cetaceans of Canada Oyster Sof1-Shell Clam American Smelt Crabs of the Atlantic Coast of Pacific Herring Spiny Dogfish Arctjc Char Canada Pacific Salmon Squid Arctic Cod Dungeness Crab Pollock Steelhead/Cutthroat Trout Atlantic Cod Grey Seal in Eastern Canada Red Hake Thorny and Smooth Skates Atlantic Groundfish Haddock Red Sea Urchin Trout in Canada's Atlantic Atlantic Hali but Harbour Seal in Canada Red Tides Provinces Atlantic Herring Harp Seal Redfish (Ocean Perch) Turbot (Greenland Halibut) Atlantic Mackerel Hooded Seal Rockfish Walleye Atlantic Pelagic and Diadromous Irish Moss Roundnose Grenadier White Hake Fish Lake Trout Sand Lance Winter Flounder Atlaniic Shellfish Lingcod Sea Cucumber Witch Flounder Lobster Sea Scallop Yellowtail Flounder