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Alcids

David A. Oehler

Natural History

The family Alcidae, or auk, is a group of marine, neritic, and pelagic birds with a circumpolar
range, found exclusively in the Northern Hemisphere. The name auk was derived from the Norse
word ãlka, given to describe the calls of these seabirds. Alcids have been divided into 11 genera
represented by 22 species. These species are represented by six major species groups divided into
two phyletic lines, one involving puffins and the other comprised of the auklets, murrelets, guil-
lemots, Dovekie, and the auks. All members of this group are highly specialized, wing-propelled,
diving birds with thickset, torpedo-shaped bodies and short wings and tails. Typical morphology
consists of plumage that is mainly black or gray above and white below. Dramatic alterations of
this plumage occur during the winter months, with certain species obtaining gray-and-white
plumage. The specific diving abilities of particular species, coupled with variations in prey items
from zooplankton to fish, alleviate competition among species. There is a close correlation between
diet to body mass and bill type (del Hoyo et al. 1996).
Due to their prey selection, alcids are normally found in the waters of the continental shelf
located in low and Arctic waters, with only members of the genus Synthliboramphus located in
subtropical waters. Foraging entails remaining on the water for a majority of the year and coming
to land only to nest and propagate. Alcids normally use islands and sea cliffs to establish breeding
colonies of up to more than one million birds in size. Nests within these colonies usually are found
within rocky substrates, earthen burrows, or inaccessible cavities, with only one species utilizing
an arboreal platform nest. Adult feeding of chicks typically follows a pattern of increased provi-
sions affected by the nutritional status of the chicks, followed by restricted amounts prior to fledg-
ing (Hudson 1979; Ashcroft 1979; Emms 1987; Harding et al. 2002).

­ Criteria­for Intervention

Very few alcid species’ chicks are encountered by rehabilitation facilities, which may be due to the
inaccessibility of most breeding colonies and nest sites. Logging activities have resulted in a small
number of Marbled Murrelets (Brachyramphus marmoratus) requiring intervention, since this
species nests on the branches of old-growth conifers (Hamer and Nelson 1995). Murres and
Razorbills (Alca torda) have an intermediate developmental strategy, allowing the chicks to depart

Hand-Rearing Birds, Second Edition. Edited by Rebecca S. Duerr and Laurie J. Gage.
© 2020 John Wiley & Sons, Inc. Published 2020 by John Wiley & Sons, Inc.