Form body :Lengthened and spindle-shaped, slightly compressed body laterally.
Size :50 cm to 100 cm (2 to 10 kg).
Coloration :Dark spots on pale bottom. Brown, green or blue back with large black spots; silver plated sides; dorsal fin with large black spots; seldom mottled caudal fin black spots. In period of spawning time: colouring bronzed or brown dark; males with red points on the sides. After the spawning time: dark colouring (black salmon).
Characteristic external features :Large mouth with strong teeth; hook pronounced in front of the jaw lower of the males in spawning time; large and very visible scales; fat fin far behind the dorsal fin; dorsal fins and pelvic in the center length of the body; caudal fin remarkably fourch in the young subjects, slightly in the adults.
How to differentiate the ombles, of trouts and salmons: Ombles: pale spots on bottom sinks.
Trouts and salmons: dark spots on pale bottom.
How to differentiate the rainbow trout, brown trout, Atlantic salmon and the ouananiche: The rainbow trout have :
caudal fin with regular lines of black spots;
square caudal fin or slightly fourchue;
fat fin with black edge and some black spots.
Brown trout have:
caudal fin with occasional and not very definite spots dark, never in line regular;
square caudal fin (slightly fourch in the young subjects);
spots sunk on the fat fin.
The Atlantic salmon and the ouananiche have*:
seldom mottled caudal fin black spots;
caudal fin remarkably fourch in the young subjects slightly in the adults;
absence of spots on the fat fin.
*The Atlantic salmon and the ouananiche is the same species. The only difference lies in the fact that the ouananiche remains in lake, whereas the Atlantic salmon migrates at sea for part of its vital cycle.
Habitat
The Atlantic salmon reproduces with the autumn (October-November) in rivers at gravel bottom and fairly fast current. The young subjects remain 2 to 5 years in river (seldom in lakes), go down then to the sea to nourish themselves and grow there during 1 to 3 years, seldom more, then turns over in river to clear.
Migration :When it reached a size of more than 10 cm, the body of young salmon lengthens and its colouring becomes silver plated. Next spring when it leaves its native river, it undertakes its first migration towards the sea and one calls then it “smolt”. The young salmon moves towards the Atlantic Ocean and leaves the gulf of the St. Lawrence before the large cold of the winter. Hivernement is probably done off the coasts of Newfoundland where water which profits from the contribution of hot water of Golfstream, usually remains between 10 and 15 ºC. Next spring, part of salmons, mainly of the males, will return towards their river of origin. The majority of the females will remain at sea for one or two years additional. They will then make a migration in the North Atlantic which will be able to as carry out them far as on the coasts from Greenland to the following autumn, then will return towards the zones of hivernement off the coasts of Newfoundland.
Food
In river, the young subjects nourish mainly larvae of insects in drift in the current. At sea, the Atlantic salmon nourishes especially small fish (lançon of America, capelan, Atlantic herring, etc) and small shellfish. Of return in river for the spawning time, the adults cease feeding and will fast until next spring.
Reproduction
Season :Autumn, October or November.
Type of spawning ground: Melts of gravel of the rivers located in the current at a depth from 0,5 to 3 m, often near a pit.
Mode : After its migration at sea, the Atlantic salmon returns to its river of origin between September and June. It remains then in pits of the river where it finds water fresh and shelters while spending less possible energy. It is the female which chooses the site of the nest and which digs it. It can make several nests during the same season of spawning time. The number of eggs that it demounting varies there, according to the weight of the female, between 2.000 and 10.000 eggs (5 to 7 mms in diameter). The males cover eggs with their seed at the very moment of the laying, then the females cover them with gravel. Generally, the female couples itself with several males and the males couple several females. Young males not having remained yet at sea, but being sexually mature, can also take part effectively in the spawning time. Contrary to his/her cousins of the coast of the Pacific, the Atlantic salmon survival with the spawning time and can reproduce several times. The eggs hatch in spring and alevins emergent of the gravel in June. The adults do not protect the nest, nor the alevins. After the spawning time, the salmons generally remain in river in the deep water sectors and turn over only next spring at sea. Approximately half of salmons will remain only a few weeks at sea before returning to clear whereas the others again make one year a complete migration at sea.
