congresos y reuniones científicas
Effects of the features and conditions of pools on the distribution of non-breeding skuas
Buenos Aires
Conferencia; Open Science Conference; 2010
Institución organizadora:
Scientific Committee on Antarctic Research
Skuas are territorial birds that preclude other birds from their feeding territories by means of aggressive behaviours. While they are in their young stages they live in groups called clubs, usually located at a pool. The aim of this work was to monitor the number of birds at each pool at Potter Peninsula (King George Island), looking for any pattern explaining any change in their distribution. We monitored the distribution of the non-breeding groups of skuas between the three pools six times a day during the light hours for seven days during January-February. There were between zero and thirty-five skuas at two of the three pools whereas the third one had zero or a few of them. The number of skuas between these two pools varied from being almost the same in each group to being zero in one and thirty-one in the other. However, we found that when these two pools became frozen or dried, the skuas moved to the third pool, which is surrounded by hills and has a reduced area compared with the other two. The smaller size of the third pool in addition to its proximity to a group of breeding pairs, which show aggressive behaviours to the birds that approach the nests, might explain why the non-breeding skuas do not chose this pool all the time, and only go there when the other two pools are without water. The water availability might also explain the difference in numbers recorded between the pools usually chosen.