Intraspecific morphological variability of blue king crab in the northern part Sea of Okhotsk

Abstract

The results in the water area from island Big Shantar to the Babushkina bay points to the existence of morphometric differences in the blue crab from the northern part of the Sea of Okhotsk. The proportions of the crab’s body change statistically significantly: in the direction from the west (severe hydrological regime) to the east (relatively warm area) crabs become more elongated in width, the right claw in all measured parameters and the height of the left claw decrease relative to the width of the carapace, and there was also a decrease in the length of the merus of the first walking leg. With the inclusion of materials from the Shelikhov Bay, in the correlation analysis, in addition to the previously found dependences (associated with the fishing length of the carapace and the height of the right claw), the clinal variability of the length of the second pereopod was also noted: its shortening occurs as in the first pereopod in the direction from west to east. When performing discriminant analysis (the sample from Shelikhov Bay was not included), the most significant morphometric differences were noted between the most remote areas: western and eastern (D2M =2,95–3,72), which, apparently, is a consequence of contrasting environmental conditions.