A characterisation of the toothfish fishery in Subareas 88.1 and 88.2 from 1997/98 to 2005/06

The exploratory fishery for Antarctic toothfish (D. mawsoni) has been operating for nine years in Subarea 88.1 and for five years in Subarea 88.2 with a large amount of data collected on toothfish and the associated bycatch. All SSRUs in the two subareas except for 881D and 882C have now been fished. The 2006 D. mawsoni catch was the second highest on record with a total of 3388 t against a combined catch limit of 3451 t. The subarea catch limit was almost reached in both Subarea 88.1 and 88.2. The management of the SSRUs within the two subareas was changed for the 2006 season as part of a 3-year experiment (SC-CAMLR-XXIV). One of the aims of the experiment was to simplify the administration of the fishery by having fewer catch limits. This appeared to be moderately successful, with only one catch limit being slightly exceeded in the 2006 season. Concentration of effort within a smaller spatial area also increased the recovery of tags by over 50% (Dunn & Hanchet 2006).
Interesting patterns are beginning to emerge concerning the size distribution of fish from the different areas in Subareas 88.1 and 88.2. The occurrence of large adult fish from relatively shallow waters on the Ross Sea Shelf as well as the occurrence of small juveniles in much deeper water on the continental slope in Subarea 88.2 suggests that depth alone does not explain all the variation in toothfish length in the areas. Further sampling from along the continental slope of the continent is needed to determine the extent of these small fish.