Crested Auklet

Identificazione

The crested auklet can measure 18–27 cm (7.1–10.6 in) in length, 34–50 cm (13–20 in) in wingspan and weigh 195–330 g (6.9–11.6 oz). They have a reddish-orange and yellow tipped bill, yellowish white irises, and white auricular plumes from their eyes to their ears. Their bodies, wings, and tails are primarily dark sooty grey, while their legs and feet are grey and claws black. The males and females are very similar, although the females have slightly smaller and less curved bills, additionally slightly smaller crests.<p>Crested auklets are known for their forehead crests, which is made of black forward-curving feathers. These forehead crests are highly variable, and can have between two and twenty three narrow forward curving feathers. The average auklet has 12 crest feathers, which are of variable length, between 8.1 and 58.5 millimetres. Auklets have auricular plumes and a bright orange bill with curved accessory plates. Like forehead crests, these features vary widely within auklet populations.<p>The crested auklet is recognized primarily by two characteristics during the breeding season. The first is its crest, a group of bristle feathers located on top of its head above its eyes. The second is a social odor that the auklets produce during the breeding season, described as smelling like tangerines. This odor originates from tiny wick feathers, located in a small patch of skin between the shoulder blades. In winter plumage, their bills are smaller and dull yellow. They lack accessory plates and their crest and auricular plumes are reduced.<p>Juveniles are similar to winter adults, but without auricular and crest plumes. Their bills are smaller, and colored a dull brownish yellow. Juveniles take 33 days to reach adult size.

Tassonomia

The crested auklet was first described as Alca cristatella in 1769 by the German zoologist Peter Simon Pallas. The specific epithet cristatella is Neo-Latin for "little crested" from Latin cristatus "crested" or "plumed". It is now placed in the genus Aethia that was introduced by the German naturalist Blasius Merrem in 1788. The genus includes four auklet species. There are no recognised subspecies of the crested auklet. Within the genus. it is most closely related to the whiskered auklet (A. pygmaea). The family Alcidae consists of many species of shorebirds including other auklets (not in the genus Aethia), puffins, razorbills, guillemots, and murres.

Nome scientifico

Aethia cristatella

Autorità

(Pallas, 1769)

Ordine

Caradriformi

Famiglia

Alcidi

Genere

Aethia

Areale e habitat

Crested auklets are found throughout the northern Pacific Ocean and Bering Sea. They are particularly prevalent during the non-breeding winter months along the Aleutian Islands, Kuril Islands and the Russian island of Sakhalin. They travel to breeding locations on the islands and shorelines of the Sea of Okhotsk and the Bering Sea during the late spring and summer. Their habitats consist of slopes, boulder fields, lava flows, and sea cliffs. They are often found with other auklet species such as the least auklet. On a daily basis, crested auklets circle 500 meters above the sea and the breeding colonies. This circling is triggered by disturbances and predators posing a threat.

Areale riproduttivo

PAL, NA : nw to ne North Pacific coasts: patchily from e Chukotka, ne Kamchatka, Sea of Okhotsk, Sakhalin, Kuril and Commander is. (e Russia); Bering Sea is. and Aleutian Is.

Areale non riproduttivo

pelagic to Hokkaido and n Honshu (n Japan) and Gulf of Alaska

Migrazione

Specie stanziale

Comportamento

Comportamento migratorio: Specie stanziale.

Conservazione

Tendenza della popolazione: in diminuzione.

Tendenza della popolazione

in diminuzione