The linear growth and some aspects of the weight growth of capelin in the Eastern part of the Sea of Okhotsk during the first year of life were characterized for the first time.

According to the averaged longterm data, the prelarva and later larva demonstrate linear growth from 6.6 to 20.4 mm in 4 early life months. Variations in the larval length composition have been demonstrated for these months, and one of determinants suggested is a very long spawning period and a very extensive spawning area where the time of emegrence is reasonably different. For the first year of life the capelin’s length can reach up to 80 mm averagely. The “age-body length” correlation is of S-shape and can be described satisfactory by logistic function. Monthly and daily capelin body length increments were calculated from formula. Some aspects of capelin’s alevin and underyearling distribution and feeding in winter have been analyzed. The growth for the first year of life can vary strongly from year to year, what indicates of unstable food supply for underyearlings in the Sea of Okhotsk. For a year since the emergence the individual weight of the Eastern part of the Sea of Okhotsk capelin has been increased from 0.12 to 2097 mg. Some aspects of larval capelin behavior on transit to exogenous feeding have been analyzed.