An updated descriptive analysis of the toothfish (Dissostichus spp.) tagging programme in Subareas 88.1 and 88.2 up to 2005/06

A descriptive analysis of the toothfish tagging programme carried out in Subareas 88.1 and 88.2 since 2001 is presented. The paper updates and revises tag-release and tag-recapture data which were presented in July 2006 at WG-FSA-SAM. In addition, the paper presents release and recapture data for non-New Zealand vessels for the 2005-06 season for the first time. However, tag data were still only available for about half of the non-New Zealand vessels for 2003-04.
A reported total of 10 775 Antarctic toothfish have been released and 225 recaptured, and 818 Patagonian toothfish released and 25 recaptured. Tagging rates by area over the past three years have been in the same proportion as the catch by area. However, recapture rates have tended to be higher in SSRUs 88.2E, 88.1C, and 88.1H. About 17% of the recaptures could not be matched to a release observation, mainly because of missing release data.
Two fish tagged and recaptured in the fishery have moved over 200 km, but the majority (>80%) of Antarctic toothfish have moved less than 50 km. Sub adult fish (80–100 cm) have tended to move further than adults over all time periods at liberty. In 2006, New Zealand vessels greatly increased the size of toothfish being tagged so that for the first time the size distribution of the tagged fish in the Ross Sea was very close to the size composition of the catch.