Least Auklet
Least Auklet
Aethia pusilla
At a Glance
The tiniest member of the auk family, no bigger than a sparrow. Abundant around islands in Bering Sea, where scores at a time can be seen perched on rock piles above the beach, chirping and chirring. Sometimes in huge flocks, winging low over the waves on very rapid beats of its small wings, or circling in the air near nesting colonies. Least Auklets are oddly variable in the pattern of their underparts, which can be anything from white to spotted to solid dark gray.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Auks, Murres, Puffins, Upright-perching Water Birds
IUCN Status
Least Concern
Habitat
Coasts and Shorelines, Open Ocean
Region
Alaska and The North
Behavior
Direct Flight, Rapid Wingbeats
Population
20.000.000
Range & Identification
Migration & Range Maps
Birds from northernmost colonies move south to evade the solid ice that surrounds their colony sites in winter. Those from Pribilof and Aleutian islands may be permanent residents in general region of colonies. Very rare stray as far south as British Columbia and Washington.
Description
6" (15 cm). Tiny, with very small bill, usually a thin streak of white behind eye. Pattern of underparts is highly variable in summer, from white to spotted to heavily mottled gray-brown. In winter, all white below.
Size
About the size of a Robin, About the size of a Sparrow
Color
Black, Gray, Orange, White
Wing Shape
Pointed, Short, Tapered
Tail Shape
Short
Songs and Calls
Various twittering notes around breeding colonies.
Call Pattern
Flat, Simple
Call Type
Chatter, Chirp/Chip, Odd
Habitat
Ocean, northern islands. May forage close to shore or far out at sea. Favors areas with turbulent water, upwellings, strong gradients of water temperature or salinity, edges of currents, or tide rips. Nests on islands in boulder fields, talus slopes, lava flows, rock crevices.
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Behavior
Eggs
One. White, becoming nest-stained. Incubation is by both sexes, 25-39 days, usually about 30 days.
Young
Both parents feed young, bringing food to nest in throat pouch. Young develops faster than young of most auks, leaves nest 25-33 days after hatching.
Feeding Behavior
Forages while swimming underwater. Fast and agile underwater but probably not able to dive very deep.
Diet
Crustaceans and other marine invertebrates. Diet in summer is small creatures that occur in swarms in cold waters, mostly very small crustaceans known as calanoid copepods, also some euphausiid shrimp, amphipods, others. Diet at other seasons not well known.
Nesting
First breeds at age of 3 years. In courtship, male perches upright and makes chattering calls; female approaches in exaggerated stretching and crouching postures, then both birds engage in bill-touching and chattering in duet. Pair-bond often lasts more than one season. Nest: In colonies located in talus slopes, rock piles, other areas with abundant small rock crevices for nest sites. No nest built, egg laid on bare rock, soil, or pebbles. Pair may re-use nest site for several years.
Climate Vulnerability
Conservation Status
Abundant, with North American population estimated at 9 million in late 1980s. Accurate counts very difficult, however, so trends in numbers hard to detect. Many populations have disappeared or declined after introduction of foxes or rats to their islands. Accidental introduction of rats to additional islands may be single greatest threat.