Craveri's Murrelet
The Craverialk ( Synthliboramphus craveri ) is a monotypic species of the family of the Auks. It is a small and hitherto little explored Auk, the year-round wearing as the Lummenalk a black and white plumage. It is found only on the coasts of the North Pacific.
The IUCN classifies the Craverialk one due to the small distribution area and the small population number as threatened ( vulnerable ).
Appearance
The Craverialk reaches a body length of 25 centimeters and weighs about 152 grams. Adult Craverialken have a year-round black-brown head and neck, as well as just such a head. In face, the black -brown coloration extends to the beak base. Trunk and tail are also black-brown. The lower chin, throat, chest and under tail-coverts are against bright white. The beak is long, slender and expires at the end to a point. The bill color is black. The iris is dark brown. The feet and legs are light blue with darker webbed.
The wings are pointed and the body is slim. Typical of Craverialken is a fast flight low over the water surface. On land, the Craverialk moves due to its far back on the body located just clumsy legs. He is unable to stand upright on his feet, but squats usually on the legs.
Young birds have, in contrast to adult Craverialken shorter wings and a shorter beak. The plumage looks deep black; he still lacks the luster that is typical of the plumage of adult birds.
Distribution area
The only proven breeding sites can be found on the coast of the Gulf of California, a 160,000 km ² of sea bordering the Pacific Ocean between Mexico and the Baja California. Other breeding colonies are possibly on the Pacific coast of Baja California. Outside the breeding season, the Craverialk in subtropical waters off the west coast of Mexico and the south of the U.S. state of California holds on. He then happens to the coast before Monterey, where it can be regularly observed in the period from mid-July to mid-October. In November, the birds return to their breeding areas.
Way of life
Craverialken preferably eat fish with a body length of four to seven centimeters. Your favorite foods are panamense juveniles of the genus Sebastes, herring and Benthosema.
The breeding colonies are found preferentially on islands with only a sparse desert vegetation and low rainfall. Some of the islands have a high level of hitting. However, mammals are missing on these islands. The nests are built in crevices and caves of the rocky coast. Eggs are laid in the months of February and March. The nest consists usually of two eggs. Scrim, which have three eggs, probably go back to a common use of a nest by two female birds. The eggs have an elliptical to oval in shape and are of a greenish - brown color. They have a speckled pattern, but this is not as pronounced as in Lummenalk. About the breeding season is not known, but presumably it is similar to the Lummenalk 31 days. The chicks hatch in March and April. You leave as when Lummenalk already with one or two days of life, the nest box and are raised on the high seas by their parents birds. The breeding begins, little is synchronized within a colony.
Stock
The stock in the Gulf of California is estimated at 5,000 pairs. Together with the non-breeding birds of the total population is estimated at 15,000 to 20,000 individuals.