Illumination of the aquatic environment to a large extent determines the motor and nutritional activity of fish, and color vision is used by them to recognize aquatic and plant organisms by their color. In some fish, color vision serves to reflexively change color for protective purposes.
Daily changes in the intensity of illumination are the cause of daily vertical migrations of fish. For each fish species, there is a certain limit to solar radiation, above which the conditions for them become unfavorable, and then they sink to a depth or take shelter in shaded places and stop eating. This is confirmed by the behavior of fish in cloudy weather – they remain active throughout the daylight hours. By the way, invertebrates, crustaceans, leading a bottom or bottom lifestyle, do not tolerate direct sunlight. Continue reading
Chebak, or Amur ide is a common fish in the Amur basin. In Primorye, it is found in almost all bodies of water, excluding the very upper reaches of mountain rivers and low-flowing small lakes. According to literature, it reaches 30 cm and 250-400 g, but my personal record is 870 g, and fish weighing 500-600 g comes across constantly. In appearance, the chebak is similar to an ordinary ide, but has a higher body and less bright fins. It spawns in May, during spawning and immediately after it, it feeds mainly on insect larvae, insects themselves, filamentous algae. Chebak in large quantities destroys eggs and juveniles of valuable fish species, so its catch is unlimited.
In spring, this fish is well caught on worms, maggots, caddis flies, pearl barley, and bread nozzles. In summer, biting is much worse. A large chebak can be caught only at night on a lamprey larva, in the daytime only small and medium specimens are caught on greens, insects, bread nozzles. Continue reading