Tuesday 21 June 2011

LAUGHING GULL. FIRST EVER RECORD FOR EXTREMADURA

Laughing Gull (Larus atricilla) in the foreground with a Black-Headed Gull (Larus ridibundus) in the background. Valdecañas Reservoir, Cáceres. 14-06-2011 (Ángel Sánchez)

On Tuesday 14 June 2011 Extremadura's first ever Laughing Gull (Larus atricilla) was spotted in Valdecañas Reservoir in the province of Cáceres. This American species is fairly similar to our Black-Headed Gull (Larus ridibundus). Gulls as a group are usually hard to identify; in this case, however, the bird was an adult in full breeding plumage so the few differences stood out well. The Laughing Gull's hood spreads much further down the neck; its mantle is a darker grey and its legs are longer. The lucky observers were Ángel Sánchez, Francisco Hurtado and Manuel Flores. Six days later, on Monday 20 June, the same bird was relocated on the opposite shore of the same reservoir, 7 km from the first site (F. Hurtado, M. Flores, Esmeralda Rodríguez y Carlota Gutiérrez).

Prima facie this seems a very surprising record, especially due to the date in late spring and the fact that the bird is an adult. A trawl of past records, however, shows both factors to be less extraordinary than might at first be thought. Maybe the most surprising fact after all is that it is an inland record, since all previous Spanish records were in coastal provinces, both on the Atlantic and Mediterranean side of the country.

Up to 2008, the most recent year with officially accepted records, a total of 51 Laughing Gulls had been recorded in Spain, 7 in the Canary Islands (CR-SEO, 2010). Still pending confirmation are two records from early 2009, in the Canaries and Málaga; there were no reported records in 2010. Up to June 2011 the Cáceres record seems to be the only one in the year (see the websites rarebirdspain and reservoir-birds). Nearly half (22) of the accepted sightings occurred in late 2005 when many storm-blown birds appeared after Hurricane Wilma.

De Juana's analysis (2006) of the 21 accepted sightings up to 2003 shows no clear seasonal pattern, with observations in almost every month of the year and peaks in winter (December-January) and during post breeding dispersal (July-August). The Cáceres record probably fits into the latter category. Broken down by ages, up to 2003 half the birds detected were adults, although there might be an in-built bias here as immatures are more likely to go unnoticed.
Sources: - De Juana, E. 2006. Aves raras de España. Lynx Edicions. Barcelona. - CR-SEO (Comité de Rarezas de SEO). 2010. Observaciones de aves raras en España, 2008. Ardeola 57(2).