Monday, 3 January 2011

THE 2010 SPOONBILL BREEDING POPULATION

Eurasian Spoonbill (Platalea leucorodia), adults and juvs, and Grey Heron (Ardea cinerea), adult and chicks. Mixed breeding colony in the Province of Cáceres. 17-06-2010 (Javier Prieta).

A previous entry of this blog gave a brief account of Spoonbill breeding in Extremadura from 2000, when breeding was first confirmed, to 2009. A best-guess figure was also given for 2010. Now that all the 2010 figures are to hand, we offer the actual info as a worldwide scoop!

The four habitual breeding colonies were visited in 2010. One of them lacked any Spoonbills and the other had succumbed to the rising waters of a reservoir. Happily the birds themselves shifted to a new site, although it was not found until June, when a single count was made. The other two colonies were visited several times. An occupied nest with no clutch was also found in a new locality.

The total 2010 Spoonbill breeding population in Extremadura was 50 pairs, shared out among four colonies: Monfragüe and environs (23), Montijo Reservoir (16), Alqueva Reservoir (10) and Alagón Valley(1). This is the biggest known figure, so the birds are still on an upward trend. Participants: Javier Prieta, Sergio Mayordomo, Emilio Costillo and Agustín Mogena.

Fortnightly monitoring of breeding in the biggest colony showed the following result: 23 nesting pairs, 19 clutches laid and 33 chicks raised by 17 successful pairs. The breeding parameters obtained were: productivity 1.43 chicks per pair, breeding success 1.74 chicks per clutch and fledgling rate 1.94 chicks per successful pair. To our knowledge this is the first time ever that detailed information has been gleaned on Spoonbill breeding in Extremadura. Participants: Javier Prieta and Sergio Mayordomo.
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Graph. Breeding Spoonbill (Platalea leucorodia). Trend in Extremadura (2000-2010).