Review of rattail and skate by-catch and analysis of rattail standardised CPUE from the Ross Sea toothfish fishery in Subarea 88.1 from 1997/98 to 2001/02

Little is known about the bycatch of skates, rays and macrourids in the target longline fishery for toothfish in the Ross Sea. Following concerns about the accuracy of reporting of bycatch raised by the 2001 CCAMLR bycatch subgroup, the processes for recording bycatch in this fishery were reviewed and the accuracy of data recording was investigated. Current systems were considered to be appropriate, and current bycatch protocols were found to perform adequately against CCAMLR guidelines. Insufficient data have previously been available to evaluate the usefulness of a standardized CPUE analysis of macrourid bycatch in this fishery. The review of data suggest that the toothfish fishery has not yet had a detectable effect on the CPUE, and hence probably the abundance of rattails. Standardised CPUE analysis may be a useful method for the on-going monitoring of this bycatch species, and continued monitoring of CPUE is suggested.