Changes in the Quantitative Characteristics of Macro- and Meiobenthos in the Blagopoluchiya Bay from 2013 to 2020 (Novaya Zemlya, the Kara Sea)

Abstract Macro- and meiobenthos of the Blagopoluchiya Bay (Novaya Zemlya, Kara Sea) have undergone significant changes in their quantitative distribution from 2013 to 2020. During this period, meiobenthos abundance has increased greatly, whereas macrobenthos abundance has decreased. Mean meiobenthos density has tripled (from 702 to 2293 ind./10 cm2), while mean macrobenthos density decreased by more than a half (from 1530 to 645 ind./m2). The observed growth of meiobenthos density was mainly due to an increase in the abundance of free-living nematodes. We suggest that the invasion of snow crab Chionoecetes opilio is one of the most important drivers of changes in benthos distribution. Following the crab invasion, there was a reduction of macrobenthic density and biomass and a compensatory increase in those in meiobenthos in the Blagopoluchiya Bay.