Examination of the gut contents of Patagonian toothfish (Dissostichus eleginoides) from the toothfish pot fishery trials around South Georgia

To undertake the 'ecosystem approach' to fisheries management recommended by CCAMLR, an understanding of the trophic relationships of exploited species is vital. Toothfish, (Dissostichus eleginoides), represents an important target species for fisheries not only in the study area around South Georgia (CCAMLR Sub-area 48.3), but also in other CCAMLR areas. To improve the knowledge on the trophic relationships of this species, stomach analyses were performed on individuals caught during the toothfish pot fishery trials undertaken in the area during the period March to May 2000. 3,640 individuals were examined and their stomach contents identified. The proportion of individuals found with empty stomachs was greatly reduced in fish caught using pots rather than longlines, increasing sample sizes. This was hypothesised to result from fish caught in pots suffering reduced levels of trauma. The most common prey item for fish caught using pots was prawns. This prey category was localised in location and depth. However prawns were not common in the stomachs of fish caught from this location using longlines. The next most common prey category was fish, as found in previous studies of this species. This confirms that D. eleginoides s an opportunistic carnivore, whose feeding habits vary dependent on the availability of food items as well as Factors such as depth.