continious+Salmon+Life+cycle


 * Salmon are born in gravel beds in streams 10 to 700 miles (16 to 1200 km) from the sea. Laid in the fall, the eggs incubate over the winter, frequently under several feet (more than a metre) of snow and ice. Their pink eggs are always covered from direct sunlight. About a month after they have been deposited in the gravel, eyes begin to show. This normally happens in late November or early December. It is essential during this time that water flow and temperature are suitable. The period of greatest mortality in the salmon's life cycle is in the egg-to-fry stage. || [[image:http://www.goldseal.ca/images/common/spacer.gif width="10" height="5"]] || [[image:http://www.goldseal.ca/images/wildsalmon/soclife2_eggs.jpg width="1" height="150" link="javascript:;"]] ||


 * In the late winter, the eggs hatch into alevins, tiny creatures with huge eyes attached to bright orange sacs. They grow rapidly under the gravel for three to four months. The orange yolk sacs contain a completely balanced diet of protein, carbohydrates, vitamins and minerals. The vitelline vein, running through the centre of the sac, picks up oxygen from the water. The fish at this stage are totally protected from predators and other hazards. Good flow of pure water is critically important to survival of alevins. || [[image:http://www.goldseal.ca/images/common/spacer.gif width="10" height="5"]] || [[image:http://www.goldseal.ca/images/wildsalmon/soclife3_alevins.jpg width="1" height="150" link="javascript:;"]] ||


 * Alevins lose their sacs, and emerge from the gravel as fry in May and June. About an inch (2.5 cm) long, they are free swimming, and are easy prey for larger fish. In the river, or a nearby lake, depending on the species, they feed and grow for periods ranging up to a year or more. (Sockeye fry move into a lake for a year, although pink and chum fry swim directly to the sea.) || [[image:http://www.goldseal.ca/images/common/spacer.gif width="10" height="5"]] || [[image:http://www.goldseal.ca/images/wildsalmon/soclife4_fry.jpg width="1" height="150" link="javascript:;"]] ||

In the early summer of their maturing year, they begin to head back to their home streams. Scientists are uncertain as to how salmon navigate back to their spawning grounds. (Current thinking ranges from theories based on their highly developed sense of smell to an ability to work out direction from the stars.) || ||  ||
 * || In spring, during the season of freshets, they head downstream to the sea. They are called fingerlings during this phase of their lives, and are up to four inches (10 cm) long. In the sea they spend varying amounts of time ranging up to five years, eating greedily and growing rapidly in the bountiful ocean feeding grounds.

With her tail the female digs a nest, or redd, in the gravel, hollowing out a cavity up to 18 inches (45 cm) deep. She prefers a place in a riffle, where the fast-running water will provide an ample supply of oxygen for the eggs. When the nest is ready, which may be weeks after the spawner has reached the gravelbeds, the female lays up to 8,000 eggs in the gravel. The male fertilizes them by covering them with a milky substance known as milt. After fertilization, the female covers the eggs with gravel, and remains on the redd until death several days later. Pacific salmon, unlike Atlantic salmon, die once spawning is complete. || ||  || By Hamza
 * Salmon stop feeding as they enter fresh water, living on stored body fats. They struggle for weeks against rapids, falls, obstructions in the form of fallen logs and rocks until, bruised and travel-worn, they reach the placid waters of the spawning river where they were born. Sockeye and chinooks are the most hardy of the Pacific salmon family, travelling as far as 1,000 miles (1,600 km) upstream to spawn. Chums, coho and pinks spawn closer to the sea.