Larus michahellis VERDE ZDM0* Mi viejo amigo "Petróleo" anillado en GALICIA (Anduriña).
En la playa de Meirás, unas 150 gaviotas.Larus fuscus MARRÓN S* Anillada en INGLATERRA Warren Claydon).
Este tipo de anillas no identifica al ave, ya que cada año solamente cambian el color de la anilla.Esta u otra, fue observada en la playa de Pantín el 19-11-2008.
Esta es la foto del año pasado.Una Larus argentatus, limpiaba sus plumas en la arena.
3 comentarios:
Hola de nuevo, Antonio.
He aquí otro interesante artículo, cuyo resumen te copio y pego:
Helberg M., Systad G.H., Birkeland I., Lorentzen N.H. & Bustnes J.O. (2009) Migration patterns of adult and juvenile Lesser Black-backed Gulls Larus fuscus from northern Norway. ARDEA 97 (3): 281-286
To explore migration patterns of Lesser Black-backed Gulls Larus fuscus breeding in northern Norway, this study presents resightings of 16 adult and 83 juvenile birds marked in this region. Adults of the endangered nominate subspecies L. f. fuscus had a low probability of being observed (only 3.5% of marked birds were observed), probably because the adults winter in areas with few observers, such as eastern and central Africa. In contrast, birds of the greyish-mantled subspecies L. f. intermedius or L. f. graellsii had a high probability of being observed (45.5%). Adults of intermedius/graellsii had a western migration route and wintered mainly in western Europe and northwest Africa. Adults exhibited a high site fidelity to wintering areas. Birds marked as juveniles had two different migration routes. (1) 30% of the observed birds crossed the Scandinavian Peninsula to Finland and the Baltic countries, and then migrated to the eastern Mediterranean (Israel and Egypt) down to eastern and central Africa (Kenya and Cameroon). (2) The other 70% followed the European coast and overwintered in UK, the Iberian Peninsula, Morocco, Mauritania and Senegal. There were no indications that juvenile migration patterns differed among subspecies as juveniles from mixed and pure fuscus colonies exhibited similar patterns. The apparent differences in migration patterns between adult and juvenile fuscus may be a result of juvenile exploratory migration.
oño:
Lo conozco, muchas gracias. El la fantástica web del mGull research organisation: http://www.gull-research.org/index.html
hay un apartado lleno de artículos de gaviotas(Pinchando en "Papaers on the WWW):
http://www.gull-research.org/papers/paper.html
Gracias a los dos por la información.
Antonio, entonces me equivoqué, la que ví yo en Pantín el pasado 21 de Noviembre y di por negra era marrón. Tiene que ser la misma, es fácil confundir y muy difícil la casualidad de que sea del año que tocara negro.
Un saludo a todos.
Paco
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