CCAMLR

The status of the worlds albatrosses are reviewed within the framework of the taxonomic changes proposed by Nunn et al. (1996) and Robertson and Nunn (this volume). The latest estimates of size of breeding populations (pairs) at all known localities of each of the 24 proposed species are presented; population trends are assessed where sufficient data are available. Despite increased efforts in population monitoring the status (i.e. population trends) of two-thirds of the worlds ca. 150 albatross populations remain unknown. For those that are known, almost half are declining. The threats currently facing each species are briefly reviewed. The best available evidence indicates that longline fishing is the most serious threat facing albatrosses today. Twenty of the 24 species are known to be killed on longline hooks, including rare and endangered species. Widespread implementation of appropriate mitigation measures is urgently required.

This paper presents a model of Sequential Population Analysis (SPA), based in catch at age data, for the evaluation of the state of the stock of Dissostichus eleginoides from the area 48.3 between 1992 to 1996. This, with the objective of knowing the results of management of this stock made under CCAMLR procedures. The model was programmed in a spreadsheet (Excel v.5) using the Solver function for the non-lineal calculus process. The application of this model, tuned by auxiliary information of effort, shows that the estimation of recruitment and the level of the TAG are extremely similar to those calculated by the WG-FSA in 1995 when F2/3 was applied, which allowed height level of spawning biomass per recruit escape. This event was even higher than that suggested by the rule of decision γl of CCAMLR. By other hand, the descent trends in Total, Fishable and Spawning Biomass showed a stabilization during the last year (1996) in relation to the previous ones. This result supports the idea that the use of the stochastic projections adopted by consensus last year, has produced an appropriate and promising assessment.

Data from individual trawls carried out by vessels operating in the krill fishery at South Georgia are examined and a range of descriptive measurements reflecting the operation of the fishery are produced. The measurements indicate that the krill fishery at South Georgia is geographically focussed, operating in a limited area along the shelf edge on the northern coast of the island. Each day a large number of trawls were undertaken by each ,vessel, with trawls being shorter in duration during the middle of the day. Daytime trawls were also generally deeper and produced a larger catch. Individual trawls were examined to establish the time required for each phase of the operation. The times associated with shooting and hauling the net were usually short and showed little variation, whereas the time associated with the actual trawl phase was longer and more variable. The distance between consecutive trawls was generally small, indicating that little effort was spent searching beyond the near neighbourhood. However, this phase of the operation took almost as long as the trawl itself and showed similar levels of variability. The range of measurements indicate that differences existed between years. Particular aspects of the variability are discussed in relation to the biology of krill, others are discussed in relation to the fishery operation.