Biological features of the Yakut crucian carp

The aim of the study is to review the biological characteristics of the Yakut crucian carp (Сarassius carassius jakuticus Лirillov, 1972). Objectives: to study the scientific literature on the biological characteris-tics of the Yakut crucian carp, the characteristics of reproduction, nutrition and the main characteristics of this species, to systematize the data and compile a literature review. The object is the Yakut crucian carp, an endemic species living in the Sakha Republic. Among the fish of Yakutia, the Yakut crucian carp (Carassius carassius jacuticus Kirillov) is one of the most common commercial fish species. The crucian carp is a bottom fish that lives in lakes and slow-flowing rivers, feeding on algae and small invertebrates. It prefers reservoirs with a large amount of vegetation, which provides it with protection from predators, as well as spawning grounds. It is very hardy, can survive in polluted waters, is highly winter-hardy, burrows into the silt in winter and can withstand a drop in oxygen to 0.1 mg/l. The climate of Yakutia is character-rized by a long winter period from April to October, water bodies are under a thick layer of snow and ice for six months and there is a sharp decrease or almost complete absence of dissolved oxygen for several months. One of the few fish species that survive in such a habitat is crucian carp, in frozen water they can reduce their metabolism and stop feeding for a long time. Crucian carp from lakes with different food re-sources and habitat conditions differ in growth rates, reproductive capacity, fat content, and taste charac-teristics. Crucian carp of the lakes of Yakutia is classified as a subspecies of golden crucian carp by its morphological characteristics and is officially named in honor of the first scientist who described it, F.N. Kirillov – Carassius carassius jacuticus Kirillov, 1972. It is considered the main commercial fish spe-cies of the lakes located in the Republic of Sakha, has important recreational, social and economic signifi-cance for ensuring the traditional economy and way of life of the indigenous population. Its distinctive fea-tures are high taste qualities, nutritional and energy value.