Growth and reproduction of the Antarctic nototheniid fish Pagothenia borchgrevinki

Summary Growth and reproductive parameters were recorded from Pagothenia borchgrevinki captured from beneath the sea ice in McMurdo Sound during October and November 1987. Fish were aged on the basis of unvalidated check rings in otoliths. Fish were estimated to be 2–7 years old. There was good correlation of estimated ages with length-frequency modes for a number of year classes. Growth was linear, and did not approach an asymptote with increasing age. Most females were in the early stages of vitellogenesis, however, 2 fish showed evidence of imminent or recent spawning activity. Males were all in the early stages of spermatogenesis. Relative fecundity was low, and this was associated with large egg size. Ovarian development was group synchronous, and it appears that spawning mainly occurs during winter.