Фаунистический анализ ихтиофауны Якутии

Abstract

The faunal analysis of fish of Yakutia is presented. The arctic (28%) and arctic-boreal (17%) fish are the basis of the fish fauna, which together make about the half of the species list (45%). They are followed by fish of Boreal plain complex (30%), Boreal-piedmont plain complex (9%) and Chinese plain complex (9%). From the other fish we note a roach as a representative of Ponto-Caspian complex and a sucker, which clearly came from North America. Another feature of the Arctic is low endemism of the fish fauna at levels of families (5%) and genera (2%). There are only 2 endemic species of 43 ones of Yakutia. As one of adaptations for life in these conditions one can consider such properties as burying in the silt for winter (2 species of carp) or even the formation of a kind of capsule by young lampreys. There is few number of fish in Yakutia which are highly specialized in food. According on nutrition character the benthophages (42%) and euryphages (30%) are dominant; there are relatively few predators-ichthyophages (17%) and zooplanktonphages (9%) and only one species of detritophages (Siberian lamprey – 2%). That is why the large intraspecific diversity of whitefish and salmon fish is interpreted as the result of evolution of northern ecosystems in the way of increasing the number of internal links and stability of northern ecosystems. Many species lay their eggs in sand (16%) or stone-gravel soil (30%) and on plants (phytophages – 19%). There is a special group of fish that show care for their offspring – 16%.