Results of the seventh Ross Sea shelf survey to monitor abundance of Antarctic toothfish in the southern Ross Sea, January 2018, and notification for research in 2018/19

At its 2011 meeting, the Scientific Committee agreed that a time series of relative abundance from a well-designed survey would be a useful input into the Ross Sea stock assessment model. In this paper we provide results of the seventh annual survey in the time series. The objectives of this survey included monitoring sub-adult (≤ 110 cm TL) toothfish in the south of SSRUs 881.J and 881.L in the southern Ross Sea (Strata A–C) using standardised gear in a standardised manner; and monitoring trends in larger (large sub-adult and adult) toothfish in two areas (both situated in SSRU 881.M) of importance to mammalian toothfish predators: McMurdo Sound in 2018, and Terra Nova Bay surveyed in 2017. The estimated relative biomass index of toothfish for the core strata showed a decrease from 2017 to a value equal to the average index early in the time series, and length and age frequency data showed the progression of cohorts through the population that were observed in previous surveys. Notification of research for the agreed 2019 fixed-effort survey is included with a catch limit of 65 t.