Comparative Analysis of Morphometric and Reproductive Parameters of Snow Crab (<i>Chionoecetes opilio</i>) of the Kara and Barents Seas

Abstract

The paper presents a comparative analysis of size and reproductive parameters of snow crab in the Barents and Kara Seas, estimated in the period 2005–2019. In the Kara Sea, females reach maturity when their carapace width (CW) is over 30 mm, and the carapace width at 50% maturation is 38 mm. In the Barents Sea, female crabs reach functional maturity when their CW 35 mm, and the carapace width at 50% maturation is significantly higher compared to the Kara Sea and is equal to 51 mm. The fecundity of individuals of the same size, caught in the Kara Sea, is slightly lower than the fecundity of individuals recorded in the Barents Sea. At the same time, the increase in the number of eggs with an increase in CW in females of the Kara and Barents Seas is linear and statistically different (ANCOVA, p = 0.0327): 27 and 22 thousand eggs with an increase in CW by 10 mm, respectively. Compared to snow crabs in other geographic regions, in the Kara Sea, the values of the studied snow crabs parameters were close to the values estimated for individuals of the Arctic eastern seas: the Chukchi Sea and the Beaufort Sea. Most of the parameters of the Barents Sea population were comparable with the parameters of the populations of the southern part of the native range (the Sea of Japan, North-West Atlantic). It was revealed that the near-bottom temperature is to a large extent a limiting factor affecting not only the distribution of snow crab in the regions of the Northeast Atlantic, but largely determines the features of its morphometric and reproductive parameters during the acclimatization of the species in the Kara and Barents Seas.