Most species of trout spawn in autumn, rainbow trout in autumn. The timing of spawning depends largely on the habitat of the fish, climate, and the specific species of trout.
Spawning
River trout spawn in autumn - in September-October. In contrast to the vast majority of salmon, rainbow trout do not spawn in autumn, but in spring. In the north, spawning takes place for 3 - 4 weeks in April - May. In Kamchatka, mykizha spawns in a very short time, only within 2 weeks, in late May - early June.
Trout, like other salmon, builds a spawning mound, the size of which directly depends on the size of the producers. Small trout living in small rivers build an egg-shaped mound, only 40-50 cm long and 30-40 cm wide. Large individuals build a hillock, reaching a length of almost two meters.
In Kamchatka, mykiss for spawning chooses areas that are better warmed by the spring sun. Therefore, for spawning, trout chooses tundra tributaries or tundra sections of rivers: the dark brown water warms up very quickly, literally attracting the sun's rays. Even the Kamchatka mykiss that lives in a mountain river is looking for its tundra area for reproduction. Only in the tundra river, where the water warms up already at the beginning of June, is the rapid development of eggs possible. Sometimes Kamchatka trout builds mounds in the most unexpected places.
Finding a suitable spawning place for trout is not easy. Sometimes females build mounds so close to each other that the boundaries of the mounds almost completely merge, and you can see only small mounds on a huge, tens of meters in diameter, common spawning ground.
Trout fry
Juveniles of rainbow trout emerge from the hillocks and begin to feed actively in the first week of July. This is very important for mykiss, as the fry need to accumulate enough fat to survive the first Kamchatka winter, which begins at the end of October and lasts until mid-May. Juveniles of rainbow trout are characterized by a very high nutritional activity.
In fish communities, small trout literally scatter fry of other salmon species to the side to grab something edible. The ability of juvenile trout to feed actively even at very low temperatures, even when the water is close to freezing, is quite remarkable.
As a rule, juveniles of most trout species stop active feeding when the water temperature drops below 8 - 9 ° C. The ability to eat greedily is passed on from juveniles to adult fish - trout are literally insatiable and indiscriminate in their food! By the way, trout is insensitive to wounds in the mouth. The fish caught on the hook in two days can again fall on the same tackle and the same bait. The remarkable feature of the rainbow trout to greedily eat everything edible in the reservoir turns out to be very important for the survival of this species.
Thus, trout has a so-called "broad biological potential" - the ability to successfully develop a wide variety of water bodies, eat a wide variety of food, demonstrate a variety of behaviors, and change their appearance in accordance with the surrounding conditions. It is in the broad potential of this species to adaptations that the success of numerous introductions of trout into rivers and lakes, which are very far from its natural range, lies.
