Morphological and biological specific features of two species of nine-spined sticklebacks of the genus Pungitius (Gasterosteiformes) from water bodies of Western Kamchatka

Abstract

Morphological and biological specific features of populations of stickleback Pungitius pungitius and Amur (Chinese) stickleback P. sinensis from salmon rivers of the western coast of Kamchatka have been studied. With reference to the mountain-tundra Utkholok River, conditions of habitation and reproduction of nine-spined sticklebacks are described. P. pungitius is capable of reproducing at a relatively low temperature (from 4–6°C) and is represented by a large amount of spatially isolated groups with low numbers of individuals. For more warm-water P. sinensis, fluctuations in numbers at tundra sites of the lower reaches of rivers depending on temperature and water content of potential spawning grounds during the season of reproduction are typical. At the sympatry of the two species (Utkholok, Snatolvayam, Kvachina, Kol rivers), a high (up to 6%) proportion of hybrids was revealed. A geographic variability of meristic characters of Western Kamchatka and Kuril populations was traced.