CCAMLR

This study examined the relative contribution of environmental variation and the seasonal demands of pup rearing on the foraging behaviour of female Antarctic fur seals Arctocephalus gazella at Bird Island, South Georgia (54° S, 38° W), during 3 austral summers (1994 to 1996). Time-depth recorders measured the diving behaviour of 72 individuals during a total of 385 foraging trips totalling 1964 d at sea. The frequencies of krill, fish and squid in the diet were estimated from prey items contained in scats. In 1996, a year of high krill abundance, females made shorter foraging trips, fewer dives and spent more time ashore than in 1994 when krill was scarce. Females fed exclusively on krill in 1996, and frequent shallow daytime diving indicated that krill were close to the surface during the day. In 1994 and 1995 deeper and longer-duration daytime dives were associated with a higher proportion of fish and squid in the diet. Foraging trip duration, ashore duration and dive frequency increased through the course of the 1995 and 1996 lactation seasons. Females, therefore, appeared to match pup demands by increasing both time feeding at sea and energy delivery to the pup on land. However, the importance of sea surface temperature and duration of night in multiple regression models suggested that physical factors were also important in explaining the seasonal pattern of fur seal foraging behaviour.

El Uruguay ha desarrollado un Programa de Relevamiento de Desechos Marinos en las áreas costeras próximas a sus instalaciones en el Área del Tratado Antártico y por tanto en el Área de la Convención correspondiente a la Subárea Estadística 48.1, donde se encuentra la B.C.A.A. (Base Científica Antártica Artigas), en Isla rey Jorge (o Isla 25 de Mayo), realizándose el relevamiento de desechos en las playas seleccionadas de acuerdo al método establecido por la Comisión, en la costa accesible desde le base en la Antártida.
La finalidad del programa es la de colaborar con las funciones de la Comisión en el análisis de la efectivización de la conservación, mediante el seguimiento de indicativos que a través de su manifestación como factores que pueden afectar los recursos vivos marinos antárticos, dan pautas de la orientación de las actividades de recolección y conexas hacia la utilización racional de estos recursos, en el cumplimiento de las disposiciones de la Convención y las medidas acordadas en sur conformidad.

To assess large whale stocks following the cessation of land-based South Georgia whaling in 1965, we report three independent sighting databases: a cruise in 1997, observations from Bird Island (NW of South Georgia) between 1979 and 1998, and mariner sightings between 1992 and 1997. All species were rare, with southern right whale sightings being the most common event. Two right whales photographed off South Georgia matched animals known from Peninsula Valdes, Argentina, a population known to be growing at 7% per annum. In contrast, blue and fin whales appear to be less abundant. A single blue whale mother-calf pair was observed off the Shag Rocks in February 1997. Extirpation of animals from this particular feeding ground is the most likely reason for ongoing low numbers of all species. Other factors may include: competition for krill by traditional predators such as penguins and seals and more recently by humans, an unusually high rate of natural mortality, habitat change such as alteration in sea ice coverage, and/or the impact of ongoing whaling. The history of this critical area of large-whale habitat and this report demonstrate the need for improved, consistent long-term monitoring of population trends for these depleted stocks.

There is a high degree of spatial and temporal variability in the population of Antarctic krill Euphausia superba across the Scotia Sea. Resolution of the spatial component of this variability requires a 'snapshot' of the krill population over the region (eg the CCAMLR B0 survey) whereas temporal changes have been addressed using time-series of samples from the diet of predators. At South Georgia krill in the diet of Antarctic fur seal Arctocephalus gazella show a good level of concordance with scientific net samples. In order to examine the potential of using krill in the diet of predators to examine both the temporal and spatial variability across the Scotia Sea it is essential to determine the level of concordance at other sites. Samples of krill from South Georgia, the South Orkney Islands and the South Shetland Islands, where predator foraging ranges overlap with intensive krill sampling areas within the CCAMLR B0 survey, will he collected from Antarctic fur sea scats between December and March using a standard methodology. This data will he used to example the level of concordance between krill in the diet or predators and from net hauls, to compare the timing of temporal changes in krill population between sites and to create a basis upon which to assess how the population structure during the CCAMLR B0 survey fits into a longer a longer time frame.