Winter dispersion in Magellanic Penguins: differences between sexes and years

MELINA BARRIONUEVO; JAVIER CIANCIO; NAHUEL MARCHISIO; ANTJE STEINFURTH; ESTEBAN FRERE

Congreso; 10th International Penguin Conference; 2019

University of Otago

Winter dispersion in Magellanic Penguins: differences between sexes and years.Melina Barrionuevo, Javier Ciancio, Nahuel Marchisio, Antje Steinfurth, and Esteban FrereMagellanic Penguin migration has only recently started to be completely studied. This species is the most migratory of the Spheniscus genus and has a major role in balancing the marine ecosystem of the Patagonian shelf, because of its large prey consumption. To study its migration, we have attached 26 geolocators (MK3 & MK4) to adults during two years 2017-2018 in Puerto Deseado, Argentina (47°45'S, 65°53'W). Preliminary analysis of 12 devises revealed that the distance covered by penguins varied between years, being almost double in 2018 compared to 2017 (x2017=21803 km, x2018=45023 km, t=3.60, p=0.005). Kernels densities also showed differences in habitat use, being penguins in 2017 more widely distributed along the Argentinean platform than in 2018, specially during May and August. Each individual had a larger path in 2018, but the used area by all penguins was smaller in 2018 than in 2017. Preliminary analysis showed that penguins locations are closely related to SST~10°C and that there were differences in SST between years. There were differences in the longitudinal distribution between sexes: males reached further distances from the coastline (t=2.01, p=0.07), and were closer to the 200-isobath (t=-2.43, p=0.04) and more time behind the 200-isobath (t=-1.98, p=0.05) than females. In 2017, stable isotopes analysis of blood samples when arriving to the colony from migration revealed differences between sexes in C13 showing a possible segregation in the diet. Studying penguin migration during many years is key to help in their conservation and to understand the health of the oceans.