Fry fish: stages of development

Anonim

Fish fry are the main planting material for pond farming. With the help of it, fishing of all reservoirs, both natural and artificial, is made.

Spawning

Spawning is a crucial time in fish. At this place it is always noisy, frequent bursts of water are heard. Spawning generally occurs at sunset. Continues all night, capturing the morning. In total, spawning can last 10-12 hours.

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Among the pond specimens, the female carp fish is very fertile. The weight of the calf is half the weight of the female itself. Caviar light green. The quantity can vary from 342, 000 to 621, 000 pieces. Few survive to sexual age. Lake and river fish, like sea fish, have many enemies who are not averse to regain caviar. The fry of fish is the desired prey of any predator.

Fish breeding

Fish stocking has four goals:

  • a commercial;
  • sports;
  • natural;
  • decorative.

Cultivation of fish in a reservoir, and after its catching and selling is a very profitable and simple matter. A real fisherman knows how to keep track of fry, how to raise, how to feed and so on. As a result, grows a big fish, sold ten times more expensive fry prices. Both river and sea fish are suitable for this purpose. Malka carp, for example, is bred by owners of artificial reservoirs, while pursuing a sporting goal. After all, what fisherman does not want to catch a big catch? Sport fishing or hunting is an occupation for real men and true anglers. This kind of vacation will suit everyone.

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Farmers pursue a natural goal. It consists in eating extra algae, destroying other species of fish by predators, and improving the reservoir. And, of course, the decorative purpose is pursued by the owners of large private houses, who can afford a small pond, or those who decide to put an aquarium in the apartment.

Do not forget that although it is a larva, the fish fry is insatiable and agile. Therefore, immediately growing fry predator fish and innocuous herbivores, you can lose one of the species. Caviar size varies from 1.25 to 1.5 mm. The younger the female, the smaller the eggs, the older ones have large ones. This has a positive effect on the development and endurance of future fish, which will be large and resistant to adverse living conditions.

Fry

At the hatching stage, the fish fry has a size from 3 to 6 mm. The first 2 days of small fish of many species are sitting in place, attached to the aquatic vegetation with adhesive glands, tail down. Nutrition occurs due to the yolk vesicle. And only on the third day the fish fry switches to a mixed diet. At this time, it feeds on zooplankton and zoobenthos. As soon as the water warms up well, the fry completely switch to pasture. They accumulate nutrients for the upcoming cold weather. Malky because there is a long and cold winter, and without the supply of nutrients, they will not survive.

Yearling

A youngster is called a fry fish up to a year old. By the end of this period, it weighs only 20-30 grams. The growth of fry is significantly affected by the food supply, oxygen concentration and water temperature. On scanty feeds, juveniles are not gaining well in height and weight. The same applies to temperature. Both at low and at high temperatures, the fry cease to feed.

How does a fish behave in winter? Malka carp, for example, cold forces to sink into the bottom pits and stop feeding. This happens at a temperature of +7 to -8 degrees. Later, when the temperature drops even lower, the fingerlings fall into anabiosis.

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In this state, any movement is minimized. Fry do not eat and practically do not breathe. If in summer, at a high water temperature, the fish takes about 60 breaths per minute, then in winter - only 4-5 breaths. After overwintering, the fish fry is called a yearling, and by the end of the year - a two-year-old. Having survived another winter season, he becomes a three-year-old.

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