Metodología de monitoreo: el crecimiento del tarso de pichones de petrel de Wilson (Oceanites oceanicus) en Antártida

ARCHUBY D.I.; CHIALE M.C.; MONTALTI D.

IBIME, Buenos Aires

Congreso; XI Jornadas de la Sociedad Argentina de Biología; 2009

Sociedad Argentina de Biología

Wilson's Petrel Oceanites oceanicus is a pelagic bird widely distributed in Antarctica and subantarctica. It nests in caves among the rocks of up to a meter of depth. The aim of this work was to develop a methodology of monitoring using the rate of growth of the tarsus of chicks of O. oceanicus in the 25 Mayo Island, South Shetland Island, Antarctica. The capture of measures was realized in the reproductive seasons 2007 (n = 21) and 2009 (n = 15). As soon as the chicks were found alone inside the nest, the length of the tarsus was registered every 3 days by a digital caliper (precision 0,01). The chicks of every season were grouped by age (5, 10, 15, 20 and 25 days of age), for which calculated the rates of average growth. The rates of growth didn't show significant differences on having compared each of 5 groups of ages in both seasons (Student's Test). Using the calculation of the rate of growth of the tarsus for the zone of study, indirect information linked to the food availability in the sea, changes in the Antarctic ecosystem product of anthropic activities or the climatic global change. It was chosen for the length of the tarsus as variable due to the fact that the margin of mistake on having taken this measure diminishes with regard to such others as, body mass, length of the head or chord of the wing. With this methodology, we propose a protocol for monitoring to this so abundant and widely distributed species.