During late March to mid-April 2020, the annual random stratified trawl survey (RSTS) around Heard Island and McDonald Islands (HIMI) was conducted in CCAMLR Division 58.5.2, with the completion of 151 stations. The survey was conducted on the FV Atlas Cove. Sampling protocols such as the design and the duration of the hauls were similar to recent surveys, but with a new set of randomly selected station points. However, only 18 of the 30 stations allocated in Plateau Deep East could be sampled due to damage to the trawl warps which prevented fishing on deeper stations.
The catch of Patagonian toothfish (Dissostichus eleginoides) () was 86.3 t which is the highest catch since the RSTS began and more than three times the average since 2015. The catch of mackerel icefish (Champsocephalus gunnari) was 7.3 t which is about average.
The estimated biomass of the target species D. eleginoides and C. gunnari in the 2020 survey were the highest for the past 10 years. Biomass estimates for the managed by-catch species unicorn icefish (Champsocephalus rhinoceratus) and Macrourus spp. were also at their highest levels of the past 10 years and the estimate for grey rockcod (Lepidonotothen squamifrons) showed the first substantial increase since 2014. Amongst the three species of skate, biomass estimates show an upward trend over the last few years with of Bathyraja murrayi also being at the highest levels for the past 10 years.
Length and weight measurements were taken for more than 17,000 fish and for more than half of those, other biological measurements were also recorded. Otoliths were collected from 763 D. eleginoides and a number of other species, and 645 toothfish were tagged and released.