Сезонная динамика размерно-возрастной структуры бурого морского петушка Alectrias alectrolophus (Stichaeidae) в приливно-отливной зоне Авачинской губы (Юго-Восточная Камчатка)

Abstract

Basing on materials collected in April-September 2014-2022 in the intertidal zone of the northeastern part of Avacha Bay, the seasonal dynamics of the size-age structure of stone cockscomb Alectrias alectrolophus living here was analyzed. It has been established that in April through late June this species is represented in the littoral by individuals in the second year of life (1+) (body length 35-67 mm, body weight 0.19-1.37 g) as well as by individuals aged 2+ to 7 years (64-143 mm, 1.09-15.9 g, respectively), which form two rather well-separated size groups of fish. In August, as the size of individuals in the second year of life (1+) increases, these groups merge, forming a single bimodal curve of size composition. In the second half of June, underyearlings of the stone cockscomb, 16-20 mm long with a body weight of 20-30 mg, begin to appear in the intertidal zone, forming the third size group from 20 to 35 mm with a body weight of 40-230 mg in July. Therefore, starting from July, in the intertidal zone of Avacha Bay, the stone cockscomb of all age groups, from underyearlings to individuals 7+ years old, lives. Data on seasonal changes in the ratio of juveniles and adult fish in the intertidal zone are presented.