Movimientos post-reproductivos de la Gaviota de Olrog nidificando en Bahía San Blas: primeras evidencias de migración parcial

COPELLO, S.; SUÁREZ, N.; YORIO, P.; GARCÍA BORBOROGLU, P.; GRAÑA GRILLI, M.; RAVASI, M. T.; SECO PON, J.P.

Puerto Iguazú

Congreso; Ornithological Congress of the Americas (XVII RAO/XXIV CBO/XCV AFO); 2017

Association of Field Ornithologists, Sociedade Brasileira de Ornitologia y Aves Argentinas

The Olrog´s gull (Larus atlanticus) is a threatened marine birdendemic of the south coast of South America. It breeds only in Argentina (95%in south of Buenos Aires province and 5% in Chubut). Theobjective was to study the spatial migration patterns of breeders from BahíaSan Blas (Buenos Aires) by means of geolocators (GLS). Ending October 2014, 32GLS were deployed on 18 males and 14 females in Islote Arroyo Jabalí Oeste. The70% of the GLS were recovered at the beginning of October 2015. A total of 8198fixes were obtained from January to August 2015 (during the non-breedingseason). Spatial density analysis (kernel) showed that during all the studiedperiod core areas of the gulls included the colony, Bahía Blanca and marineareas to the south of the colony. However, 23 ringed Olrog´s gulls banded inBahía San Blas were sighted during the non- breeding season between the2009-2013 in coastal areas of Quequén, Mar del Plata and Mar Chiquita. Theseresults are relevant for the knowledge of the seabirds? movement ecology andalso highlighted the importance of enforced protection measures during the non-breeding period in breeding areas of the species such as Bahía San Blas andBahía Blanca.