Abstract
We present information on a new colony of Olrog’s Gull Larus atlanticus, endemic to Argentina and internationally considered as vulnerable. The colony, visited on November 16 2001, was on an islet located in the Canal Ancla (38°56'S, 62°11'O), 13 km southeast from Punta Alta. Nests were distributed in four groups of between 17-238 nests, adding to a total of 340 active nests. The Olrog’s Gull colony was located within a colony of Kelp Gulls (Larus dominicanus). Olrog’s Gulls did not breed in this islet during 1995. As this species may change colony sites between breeding seasons, future work should evaluate their spatial and temporal patterns of habitat use.
References
BIRDLIFE INTERNATIONAL (2000) Threatened birds of the world. Lynx Edicions y BirdLife International, Barcelona y Cambridge.
DELHEY JKV, PETRACCI P Y GRASSINI CM (2001) Hallazgo de una nueva colonia de la Gaviota de Olrog (Larus atlanticus) en la ría de Bahía Blanca, Argentina. Hornero 16:39–42.
PARKER TE III, STOTZ DF Y FITZPATRICK JW (1996) Ecological and distributional databases. Pp. 113–136 en: STOTZ DF, FITZPATRICK JW, PARKER III TA Y MOSKOVITS DK (eds) Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.
YORIO P Y HARRIS G (1992) Actualización de la distribución reproductiva, estado poblacional y de conservación de la Gaviota de Olrog (Larus atlanticus). Hornero 13:200–202.
YORIO P, PUNTA G, RÁBANO D, RABUFFETTI F, HERRERA G, SARAVIA J Y FRIEDRICH P (1997) Newly discovered breeding sites of Olrog’s Gull Larus atlanticus in Argentina. Bird Conservation International 7:161–165.

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
