Bird Families

Aleutian fawn

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Home / - Next species Volume 4 / Aleutian fawn / Ptychoramphus aleuticus Pallas, 1811

Species name:Aleutian fawn
Latin name:Ptychoramphus aleuticus Pallas, 1811
English name:Cassin's auklet
Latin synonyms:Uria aleutica Pallas, Aethia aleutica Pallas
Detachment:Charadriiformes
Family:Acuts (Alcidae)
Genus:Aleutian Fawn (Ptychoramphus Brandt, 1837)
Status:A rare vagrant species.

Description

Coloring. Male and female in breeding attire. There is no sexual dimorphism. The top is blackish-slate, the sides of the head, chin, throat and craw are somewhat lighter, dark smoky gray, the underwings are gray-brown, the chest and belly are white (there is no sharp border). Above and under the eye along a white spot, at the base of the mandible there is a light spot. The iris is white, the beak is pointed black, the legs are bluish or bluish-brown. The throat sac in birds that have started breeding begins to lengthen, reaching 130 mm by the time the chicks emerge, and in the fall it shortens to 65 mm (Buturlin, 1934, Thoresen, 1964, Manuwal, 1978, Tuck, Heinzel, 1978).

Male and female in winter dress. The color of the plumage is similar to that of the breeding, but the throat is light (Tuck and Heinzel, 1978).

Downy outfit. The top varies from black to brown-gray, the bottom - from gray to fawn or pale gray. The area of ​​the skin around the eyes is not pubescent. Paws are pink with black claws. The eyes are dark brown. Up to 10-12 days, chicks are still small and fluffy. Compared with other species, it is easy to mistake them for 2-3 days. The color of the legs changes to dark gray with a bluish tinge on the 10th day. The first feathers appear on the 12-16th day, first - on the belly, sides, midline of the back and wings, at 18 days - on the head and neck. Primary flight feathers develop at 20–23 days. Juvenile plumage forms by 30 days of age, when most of the down is replaced by feathers, but patches of down can remain on the back of the head and rump for up to 42 days. Tail feathers begin to develop on the 14th day, at 18 days they reach 10 mm and by the time they fly out - 40 mm (Thoresen, 1964).

Chick outfit. In color, it almost does not differ from an adult, but the throat is white, the beak is somewhat shorter (Gabrielson, Lincoln, 1959, Thoresen, 1964).

First wedding dress. Very similar to an adult, with a shorter beak and a slightly whitish throat. Eyes are dark or with dark streaks. There is usually no prelingual sac. Until the end of summer, the plumage remains fresh, black-gray, like in molted adults, without a brown tint (Gabrielson, Lincoln, 1959, Manuwal, 1978).

Spread

Nesting area. Islands of the western coast of North America from the Alaska Peninsula, the Aleutian Islands, the Kodiak and Shumagin Islands to 27 ° N. sh., California Peninsula, Guadalupe Islands. All colonies known to date are located south of 57 ° N. sh., but the species is regularly recorded north of the Strait of Alaska (Thoresen, 1964; Stepanyan, 1975; Tuck, Heinzel, 1978).

Figure 28. Distribution area of ​​the Aleutian pyzhik
a - the border of the nesting area, b - places of flights in the USSR

Wintering

Hibernates within the nesting area, roams in the same area (Belo-Polsky, Shuntov, 1980). The population of the Farallon Islands has settled; outside of breeding, fawn visit the nesting sites throughout the year, but irregularly, usually at night (Manuwal, 1974).

Aleutian pyzhik was caught in the Kuril Islands by I. G. Voznesensky, who worked there in 1844-1845. Liechtenstein in 1854 mentions a specimen of the Aleutian fawn "from Kamchatka" in the Berlin Museum (quoted from Buturlin, 1934). Probably the same cases are meant by K. Vori (Vaurie, 1965) and L.S. Stepanyan (1975).

Introduction

Aleutian fawn (lat. Ptychoramphus aleuticus ) is a small seabird of the auch family. The only representative of the genus.

1. Appearance

The plumage is dark gray, lighter on the abdomen. The beak is yellow, there is a white speck under the eye. It differs from lyurik in dark sides. In winter, the throat is light.

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