Talas Naked Osman
The coloration of the Talas naked osman is quite beautiful. It can be easily recognized by its small but well-defined dark brown spots located on its back, head, and fins. The scales, which are present only on the lateral line, stand out with a light stripe against the background of these spots.
Spawning occurs during the day in shallow rapids, and the eggs are carried downstream by the current to deeper areas covered with pebbles and gravel. The eggs of the naked osman are slightly larger than those of the scaled variety. In summer, the naked osman stays in the lake itself, found from shallow waters to depths of about 40 meters, both on rocky and muddy bottoms among thickets of char. The young primarily feed on larvae of tendipedids and other insects. The immature ones, measuring from 10 to 14 cm, mainly feed on char, with a lesser extent on mollusks, while in larger individuals, the significance of mollusks in their diet increases and fish also appear. The osman grows slowly.
In fast rivers, osmans rarely grow to large sizes. The largest ones measure 25–30 centimeters in length and have a corresponding weight for that length. Life in the extreme conditions of a cold and fast river forces the osman to expend a lot of energy searching for food and resisting the water flow.
It can be found in the turbulent headwaters of rivers where there are no scaled osmans, in cold (6—8°C) and warm karasuk lakes, in warm and cold-water lakes.
Fish