Distribution and some features of biology of sea raven <Emphasis Type="Italic">Hemitripterus villosus</Emphasis> (Hemitripteridae) in the northwestern part of the Sea of Japan

On the basis of long-term (1981–2008) observations, it was shown that, in the northwestern part of the Sea of Japan, sea raven Hemitripterus villosus is a common species with low, but stable numbers and it is a part of elittoral ichthyocenoses. During the year it performs wintering, feeding, and spawning migrations within the shelf and the upper part of the continental slope occurring from almost the water’s edge to a depth of 550 m. Highest density of sea raven is observed in Peter the Great Bay and the lowest is observed off the coasts of northern Primorye. Maximum length of H. villosus in the northwestern part of the Sea of Japan reaches 57 cm, and the modal group of fish consists of fish with a length of 25–45 cm (75%). In Peter the Great Bay, in the summer period, individuals with a length of 11–50 cm feed mainly on mass fish species; the value of daily ration of H. villosus varies from 1.6 to 3.2% of body weight, averaging 2.5%. According to an expert estimate, the biomass of sea raven in the northwestern part of the Sea of Japan reaches 2000 t.