Salmon is a cold-water migratory fish that spawns upstream. According to the time of upstream, it can be divided into two biota: summer biota and autumn biota. Only autumn salmon are found upstream in China, and most of them spawn downstream, and only a few reach upstream. After the fertilized eggs hatch, the larvae lurk in the dark between the gravel, and when they grow to millimeters, they begin to fall into the river and go to the sea. When they reach maturity, they will return to the freshwater river and return to the original breeding site to lay eggs.
Choose a place with clear water quality, rapid water flow, water temperature of 5~7℃ and gravel as the bottom material to lay eggs. The eggs are laid in a pit with a diameter of about 1 m and a depth of 30 cm. After spawning, the parents were emaciated and died after 7~ 14 days. Only breed for life 1 time.
Extended data:
First, life habits
Fierce, carnivorous fish, young fish eat benthos and aquatic insects, and after entering the sea, they mainly eat small fish such as herring and herring.
Second, the nutritional value
Salmon is a relatively precious large-scale economic fish, weighing more than 6.5 kilograms at the maximum, rich in fat and delicious in meat. Its eggs are one of the precious aquatic products in northeast China, with high nutritional value.
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