Saturday, 25 June 2011

Pigeon guillemot

Cepphus columba

Photo by Glenn Bartley (Glenn Bartley Nature Photography)

Common name:
pigeon guillemot (en); airo-d'asa-branca-do-Pacífico (pt); guillemot colombin (fr); arao colombino (es); taubenteiste (de)

Order Charadriiformes
Family Alcidae

The pigeon guillemot is found in the North Pacific, breeding in Russia from the Kuril islands and the Kamchatkan Peninsula to the eastern tip of Siberia, and from the western tip of Alaska down through the Pacific coast of Canada and the United States to southern California. This includes colonies on the Commander and Aleutian islands.

These birds are 30-35 cm long and have a wingspan of 58-60 cm. They weigh 450-550 g.

Pigeon guillemots are pelagic, fishing out in the sea and only coming to shore to breed. They nest in rocky shores, cliffs and islands.

These birds take fish and marine invertebrates, including Pacific sandfish Trichodon trichodon, capelin Mallotus villosus, cods (Gadidae), sculpins Myoxocephalus, gunnels Pholis laeta, pricklebacks Lumpenus sagitta and some flounders (Pleuronectidae). Invertebrates include red rock crab Cancer oregonensis, shrimps (Crangon, Pandalus and Heptacarpus), polychaetes, gastropods, and a bivalve mollusks.

Pigeon guillemots start nesting in March-April. They nest under logs, in rock crevices or holes, under bridges, in tree roots, in abandoned puffin burrows, pilings, and waterfront structures, such as wharves, bridges, navigation aids, walls of disused buildings, and old tires, pipes, boxes, and beached ship hulls, all usually within 30 m of the high water mark. The female lays 1-2 greenish or bluish-white eggs with brown marks. The eggs are incubated by both parents for 30-32 days. The chicks are fed by both parents and fledge 29-39 days after hatching.

IUCN status - LC (Least Concern)
This species has a very large breeding range and a global population of 470.000 individuals. The population in North America may have undergone a slight increase, but overall the population trend is believed to be stable. This population is not considered threatened at present.

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