Size Structure of Mature Snow Crabs Chionoecetes opilio (O. Fabricius, 1788) (Decapoda, Oregoniidae) in the Kara Sea

Based on the materials obtained in the Kara Sea, the size structure and sexual maturity of the male population of the invasive snow crab opilio (Chionoecetes opilio) are analyzed. Observations in the southern bays of the Novaya Zemlya archipelago and the Novaya Zemlya depression showed that the bulk of male crabs reach maturity at a carapace width (CW) above 60 mm. All captured males with CW of more than 67 mm underwent terminal molt. Only two males caught in the Novaya Zemlya trough reached the established commercial size of carapace width (CW) of 100 mm. The most numerous size group of adult males in the bays had CW of 60 mm, and 80–90 mm in the Novaya Zemlya trough. The obtained data allow us to assert that harvesting crabs with CW of 80–90 mm will not result in the removal of immature individuals and will not reduce the reproductive potential of the Kara Sea population beyond predicted levels of sustainable fishing.