Monday 10 January 2011

GOOSANDER. ANOTHER FIRST FOR EXTREMADURA

Goosander (Mergus merganser), first winter female. La Torrecilla, Plasencia, Cáceres. 09-01-11. Top, resting on land among a small flock of Teal (Anas crecca); Bottom, swimming next to a female Shoveler (Anas clypeata). Photographer: Javier Prieta. See more photographs.

Extremadura clocks up another first, the third new species since this blog came online eight months ago in May 2010. The species this time is Goosander (Mergus merganser), joining the Pied Billed Grebe and Buff-Breasted Sandpiper, which featured in earlier blog entries.

The sawbills are fish-eating diving ducks that take their name from the serrated edges of their thin beaks. A solitary female Red Breasted Merganser (Mergus serrator), spotted by Santiago Villa in Brozas back in March 1997, was hitherto the only sawbill previously seen in Extremadura. Now another young female, this time of its cousin species the Goosander, found by Sergio Mayordomo in Plasencia on 9 January 2011, can be added to this meagre list (other observers: Ricardo Montero and Javier Prieta; on 11 Jan was found by SM, JP, Miguel Ángel Muñoz y Eva Palacios).

The Goosander breeds in the Taiga of North America and Eurasia, wintering further south but without reaching Spain, where it is classed as a rare vagrant. From 1984 to 2008 there were only 28 accepted records involving 62 birds, all on mainland Spain (CR-SEO, 2006-2010). In Portugal it has been recorded only twice (Catry et al. 2010). According to De Juana (2006) it turns up in Spain only when driven further south by cold spells on continental Europe, so some years there are no records at all. Until 2003 only one bird among 28 records turned up in an inland province (Navarre) and only two were in the southern half of the country (Albufera de Valencia and Odiel, Huelva). All the birds were recorded between November and March, with 83% of the birds being seen in only three winters, females clearly outnumbering drakes (2:1). In the 2004-2008 period only five single birds were accepted (CR-SEO, 2006-2010); these records were atypical since three of the birds turned up inland (Huesca, Ciudad Real-Toledo and Granada) and two of them were in spring (one in May and the other in June). In 2009, a year for which the rarity report has not yet been published, there were several typical records in Galicia and Asturias and another in Zamora (Rare Birds in Spain).

The cold snap that hit the centre and north of Europe in December 2010 produced a considerable influx of Goosanders into Spain. To find something similar we need to go right back to 1984-1985, with 6 records involving a total of 22 birds. The first bird appeared on 04/12/2010 with over 30 birds then being observed in 20 different sites in 15 provinces by 10/01/2011. As well as the sheer number, this wave of observations is also notable for the total lack of drakes, only females being seen, and also because over half of the provinces involved, 8, were inland (sources: Rare Birds in Spain and Reservoir Birds).

Spanish provinces with Goosander (Mergus merganser) records between 04/12/2010 and 10/01/2011 (sources: Rare Birds in Spain and Reservoir Birds).

References: - De Juana, E. 2006. Aves raras de España. Lynx Edicions. Barcelona. - Catry, P., Costa, H., Elias, G. and Matias, R. 2010. Aves de Portugal. Ornitologia do território continental. Assírio & Alvim. Lisbon. - CR-SEO (SEO Rarities Committee). 2006-2010. Observaciones de aves raras en España. 2004-2008. Ardeola 53, 54, 55, 56 and 57.