Life Cycle

The grade 6 class of Jakeman All Grade School is participating in the Fish Friends program developed by the Atlantic Salmon Federation. This program, designed for elementary school children, promotes the public awareness and education of fisheries conservation and preservation.The grade 6 class has a specially designed incubation unit that holds approximately 100 Atlantic Salmon eggs. Students monitor the tank temperature daily and are responsible for the care of these larvae from when they first hatch (alevin stage) until they reach the fry stage of development. Students will then return these tiny fish to their river of origin.

Atlantic Salmon, like other fish and animals, have a life cycle. Life cycles start when an organism's life begins, and ends when the organism dies.

Did You Know? An average adult salmon lays 1550 - 1750 eggs per kg of body weight, so a 5 kg female will lay 7700 - 8800 eggs. If a female lays 8200 eggs, how many of these eggs will yield fish that can survive long enough to spawn themselves? Lets find out...
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STAGE 1 EGGS

Hatching

Adult female salmon lay eggs which are fertilized by male fish. This process is known as spawning. These eggs are laid in a nest called a redd, which is buried under 12-15 cm of gravel at the bottom of a stream. Spawning usually occurs in late fall. 8200 eggs are laid.

STAGE 2 ALEVIN

Sacfry

The eggs remain buried in the gravel for the winter months, and hatch in early spring as alevin or sacfry. These tiny fish have a yolk sac which is their food supply, so they don't need to hunt for food.

5000 alevin will survive. SacFry4_small.jpg (1701 bytes) Yolk Sac

STAGE 3 FRY

A month or so after hatching, alevins must start searching for food. They emerge from the gravel as fry. It is at this stage in the classroom project that students must begin feeding the tiny fish.

775 fry will survive in their natural habitat.

STAGE4 FINGERLING

When the young salmon are about 8 cm long they are called fingerling. This is when the fish are 6-12 months old.

400 fingerling will survive this stage of development.

STAGE 5 PARR

Parr Markings

Fingerling become parr on their first birthday. The fish's colouring and markings change, and small red dots appear on their sides which help the parr hide from their enemies.

315 parr will survive this stage of development.

STAGE 6

SMOLT

During the 2nd, 3rd or 4th, year of life, parr become smolts. Now they change colour from greyish - brown to gleaming silver. Smolt migrate to the ocean during early spring.

80 smolts will survive this migration journey.

STAGE 7 SEA FISH

Migration

After spending 1-4 years at sea, the smolts will migrate upstream to spawn. They will return to the same river where they hatched. Fish that spend only one year at sea before returning to their original river are called grilse, whereas fish that spend more than one year at sea before migrating upstream are known as largefish.

10 fish will successfully migrate to their original river.

STAGE 8 SPAWNERS

Slink

After fish have spawned, they turn black in color and have a golden shine. These fish are called slinks or are sometimes known as kelts or blacks. After spawning, many fish die, especially males, but some fish have been known to spawn many times.

ONLY 2 spawners will survive.

Eggs

Alevin

Fry

Fingerling

Parr

Smolt

Seafish

Spawners