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Auks, puffins, and murres

(Alcidae)

Class Aves

Order Charadriiformes

Suborder Alcae

Family Alcidae


Thumbnail description
Small to medium-sized marine diving birds with short, narrow wings, short tails, and a great variety of bill shapes and sizes

Size
6–18 in (12–45 cm): 0.17–2.4 lb (80 g–1.1 kg)

Number of genera, species
13 genera: 23 species

Habitat
Oceans, shorelines, and islands

Conservation status
Extinct: 1 species; Vulnerable: 4 species

Distribution
Circumpolar distribution in North Atlantic, North Pacific, and Arctic oceans

Evolution and systematics

The auks are quite different, both in appearance and behavior, from all other waders and gull-like birds. Although the alcids have been associated with several different families in the last century—penguins (Spheniscidae) and grebes (Podicipedidae) among them—current taxonomy leaves Alcidae in a separate suborder of the Charadriiformes. The predominance of species that breed in the North Pacific indicates that the family's ancestry may lie in that region, and some fossil evidence supports this premise. Existing geological information puts modern Alcidae in the North Pacific as early as six million years ago, but also suggests an unknown ancestry extending over 40 million years before that time. While the suborder is uniform enough to include all of the auks in one family, there are still some very interesting differences between species, both in physical characteristics and in life patterns. Not surprisingly, there are also some discrepancies among experts in alcid taxonomy. As of 2002, ornithologists recognize 13 genera and 22 living species, with some experts condensing the number of genera to as few at 10.

Although there are no formal subfamilies, the living auks can be divided into eight lineages. The dovekie or little auk (Plautus alle, also known as Alle alle) is the sole member of the first group. The second group numbers three species: the razorbill (Alca torda), the common murre (Uria aalge), and the thick-billed murre (Uria lomvia). Three species of guillemots (Cepphus) form the third group, while the fourth and fifth are comprised of murrelets: Brachyramphus (two species) and Synthliboramphus (four species), respectively. The sixth group holds five species of auklet (genera Ptychoramphus, Cyclorrhynchus, and Aethia) while the seventh holds a single species, the rhinoceros auklet (Cerorhinca moncerata). Comprising the final group are three species of puffin (Fraturcula). The great

auk (Pinguinus impennis), a flightless North Atlantic seabird and the only extinct member of the Alcidae, disappeared in 1844.

Physical characteristics

The auks are well-developed for their role as marine birds; so well, in fact, that they use land only for breeding. Living species range 6–18 in (12–45 cm) in length and weigh 0.17–2.4 lb (0.4–1.1 kg). (The extinct great auk [Pinguinus impennis] reached over 11 lb [5 kg].) The wings are relatively narrow and short, and the tail is short. The foretoes are webbed, with no toe on the back of the foot. The plumage is generally black, white, and gray, although the Brachyramphus murrelets develop brown summer plumage.

Many peculiarities distinguishing this family involve adaptations to diving and underwater "flight." These include dense, firm plumage; short, narrow wings; displacement of the feet toward the back, and consequently, a rather upright posture when standing on land; great development of the sternum, the coracoids, and the furcula; strongly developed breast muscles; large air sacs; a high blood hemoglobin content when compared to many land birds; and a high concentration of erythrocytes. While the alcids share many adaptations with their unrelated ecological counterparts in the Southern Hemisphere, the penguins (family Spheniscidae), the northern seabirds have almost all retained their flying abilities.

The larger species lose all their flight feathers at once in a molt shortly after the summer breeding season. The auks are then flightless for up to 45 days. Due to their small wings, most auks need a running, splashing start on the surface of the water to become airborne.

The bills of auks display a bewildering variety of forms and functions, unmatched by any other family and especially striking in such a small family. The razorbill was named because its long, sharp bill looks like an old–fashioned straight razor. The puffins have very deep bills that are laterally compressed. The dovekie has a very short, pointed bill that resembles that of a passerine. The guillemots have simple, straight bills. The parakeet auklet (Aethia psittacula) has the oddest-looking bill, with a lower half that turns up towards the tip—this feature apparently facilitates the capture of jellyfish.

Distribution

Exclusively in the Northern Hemisphere, throughout the Arctic, North Atlantic, and North Pacific.

Habitat

Alcids live almost exclusively on the surface of colder ocean waters, with breeding on shorelines, seaside cliffs, islands, and (in a few species) coastal forests.

Behavior

Their flight is fast and boisterous, although rather clumsy in appearance. The relatively small wings of most species require fast wingbeats, and most auks need some distance to become airborne. Auks are most often seen flying low over the surface of the ocean. Auks are superb swimmers and divers: studies using depth recorders attached to the birds have indicated that some species may reach depths of 600 ft (183 m). Under water, auks propel themselves with powerful beats of their half-open wings, while the legs are stretched back with the webbed feet functioning as a rudder.

Feeding ecology and diet

Auks draw their sustenance exclusively from the ocean. The larger species, such as murres, razorbills, guillemots, and puffins, prefer small fish that live in great numbers in the open ocean or on the ocean floor; they also feed, to a lesser degree, on small cephalopods, larger crustaceans, and other invertebrates. The smaller species, such as the dovekie, feed mainly on crustaceans, mollusks, chaetopods, and various other marine invertebrates. Many species fly well out over the ocean in search of food. Marbled murrelets (Brachyramphus marmoratus),

which nest further from the water than other auks, will commonly fly 50 mi (80 km) from their nesting areas to forage.

Auks do not skim food from the surface of the water, nor do they dive into the sea directly from the air. Instead, they rest on the surface, then poke their heads under and tip forward, thrusting their bodies down and driving themselves forward with their wings as they swim in search of prey. This technique is called "pursuit diving."

Reproductive biology

All auks are monogamous, although pairs do not always stay together for life. Most species also show a strong inclination to return annually to the same nesting site.

Eight species of alcids copulate only at sea, a somewhat mysterious breeding strategy. Theories include avoidance of predators, avoidance of interfering males of their own species, and the possibility that females use this situation to select the more fit males.

Both sexes share in incubation and rearing of the young. Most species lay only one egg, the weight of which is roughly one tenth to one fifth that of the female. The newly hatched chicks, which are able to see, are covered with a dense downy coat. In a strategy unique to the Alcidae, young birds of several species leave the nest two to three weeks after hatching and venture out to live on the sea with their male parent until they become independent. The plumage of the juveniles resembles the winter plumage of the adults in color. Males and females have the same breeding plumage.

Conservation status

While the great auk is extinct, none of the extant species is considered Endangered. Several species, however, are classed as Vulnerable, with Xantus's murrelet (Synthliboramphus hypoleucus) and the marbled murrelet of particular concern. Xantus's murrelet, whose breeding grounds are restricted to the Baja peninsula and coastal islands off southern California, is threatened by introduced predators such as cats and rats as well as habitat degradation. The marbled murrelet population in the contiguous United States as of 1999 (perhaps 17,000 pairs) was estimated to be declining at about five percent per year due to habitat loss, and the U.S. Fish and Wildlife Service lists the species as Threatened. Human predation is no longer a critical threat to alcids, but oil spills and other ecological threats are cause for concern. Thousands of auks drown every year in fishing nets.

Significance to humans

The auks no longer support the kind of industry that flourished on the bodies of great auks, but significant hunting still takes place. Several species are hunted for subsistence in Greenland, Canada, and Alaska, and large hunts for two species are permitted in Newfoundland.

Species accounts

List of Species

Common murre
Thick-billed murre
Razorbill
Black guillemot
Puffin
Dovekie
Marbled murrelet
Great auk

Common murre

Uria aalge

taxonomy

Uria aalge Pontoppidan, 1763, Iceland. Five subspecies.

other common names

English: Atlantic murre, common guillemot, thin-billed murre; French: Guillemot marmette; German: Trottellumme; Spanish: Arao Común.

physical characteristics

15–17 in (38–43 cm); 33.5–37 oz (950–1,050 g). Black to brownish head and upperparts; white underparts. Black bill is long, slender, and pointed; mouth lining is yellow.

distribution

North American coast from New England northward to Labrador, central California to northern Alaska, and from Siberia as far south as Japan and Korea.

habitat

Rocky coastlines and adjoining seas.

behavior

Pelagic. Rarely comes ashore except to breed. Common murres are fast fliers and sometimes travel in large flocks. Their most common vocalization has been described as purring.

feeding ecology and diet

Primarily fish; less commonly consumes a variety of marine invertebrates.

reproductive biology

Breeds in large colonies, often with other species. Courtship and copulation take place on land. A single egg is laid on bare rock. The egg is marked with a distinct pattern so the parents can recognize it; a common murre will find and retrieve its own egg if the egg rolls away. Incubation takes 32–35 days. The chick is fledged at 20–22 days after hatching and follows the male parent out to sea to complete the period of parental care.

conservation status

Widespread and numerous. Concern in some areas due to hunting and habitat degradation.

significance to humans

The common murre is hunted legally in large numbers in Newfoundland.


Thick-billed murre

Uria lomvia

taxonomy

Uria lomvia Linnaeus, 1758, Greenland. Four subspecies.

other common names

English: Brunnich's guillemot; French: Guillemot de Brünnich; German: Dickschnabellumme; Spanish: Asao de Brunnich.

physical characteristics

15–17 in (38–43 cm); 28–38 oz (800–1,080 g). Largest living alcid. Blackish head and upperparts; whitish underparts. Black bill is shorter and heavier than U. aalge and has a whitish line along the edge of the upper mandible near the gape.

distribution

North American coast from Maine to Baffin Island and the southern half of the Greenland coasts. Also coastlines in northwestern Canada, most of Alaska, the Aleutians, Kamchatka, and northern Japan, plus Arctic islands and the Arctic coast of Norway.

habitat

Rocky cliffs and adjoining seas.

behavior

Generally a more oceanic bird than the common murre. Their ranges are similar, although the thick-billed tends to stay further north. At sea, they are found in small groups or alone, but they congregate in thousands at established breeding cliff sites.

feeding ecology and diet

Fish, especially Arctic cod (Boreogadus saida), comprise most of the diet. A variety of crustaceans are also eaten.

reproductive biology

Thick-bills brood in huge rookeries. Brooding is done on bare rock, often on narrow ledges of cliffs, with incubation lasting an average of 32 days. Thick-bills are one of several alcid species in which a replacement egg may be laid if the first is broken or fails to hatch. When the chick is fledged, it follows the male parent out to sea.

conservation status

Widespread and numerous: at least two million breeding pairs in Iceland alone. No special concern.

significance to humans

The thick-billed murre is hunted legally in large numbers in Newfoundland.


Razorbill

Alca torda

taxonomy

Alca torda Linnaeus, 1758, Baltic Sea. Two subspecies.

other common names

English: Razor-billed auk; French: Petit Pingouin; German: Tordalk; Spanish: Alca Común.

physical characteristics

14.5–15.5 in (37–40 cm); 18–32 oz (515–900 g). Blackish head and upperparts; whitish underparts. Black bill is larger than Uria and appears rectangular; broken transverse white line across both mandibles and another white line extending from base of culmen to eye.

distribution

Winters in the open sea on the North Atlantic. Breeds on the both coastlines of the North Atlantic.

habitat

Rocky coastlines and adjoining seas.

behavior

The adults are silent at sea, while the juveniles give a whistling call. At the breeding sites, the adults are very vocal. When members of mated pairs approach each other, they will bow, then growl, and then put on a show of "billing," in which the head is tossed about, the bill swung all around, and the mandibles clicked together.

feeding ecology and diet

More than 90% of a razorbill's diet is fish, although the bird will ingest some invertebrates.

reproductive biology

Razorbills most often breed in breed in small groups, usually together with murres. The single egg is white or light cream-colored with brownish spots and streaks. Young razorbills are born after about 35 days and get their second down coat 17–22 days after that, when they have reached a quarter of the adult weight. At that time, they leave the nest to go to sea with their male parents.

conservation status

Some razorbills are killed during legal hunts for murres. Razorbills are the least numerous of North American Atlantic auks, and the population declined significantly in the 1960s and 1970s. However, the species is not in imminent danger.

significance to humans

None known.


Black guillemot

Cepphus grylle

taxonomy

Cepphus grille Linnaeus, 1758, Baltic Sea. Five subspecies.

other common names

English: Tystie; French: Guillemot à miroir; German: Gryllteiste; Spanish: Arao Aliblanco.

physical characteristics

11.8–13 in (30–33 cm); 1.6–3.9 oz (325–550 g). Overall black plumage except for white wing patches and underwing-coverts. Black bill is slender and pointed; mouth lining, legs, and feet are red.

distribution

Circumpolar distribution, with breeding grounds from the Gulf of Maine intermittently spaced across the top of North America to Alaska and across the Arctic coast of Asia. Winters in the North Atlantic, venturing as far south as France, although they generally stay closer to shore than many auks.

habitat

Rocky shores, including islands, and adjoining seas.

behavior

Strongly territorial concerning nesting sites, to which they return year after year. Rarely nests in mixed colonies with other species. Engages in courtship displays involving bowing, whistling, etc. Uses a variety of calls, mostly high-pitched, while at the breeding grounds. Swimming in line, apparently for cooperative feeding, has been observed.

feeding ecology and diet

Primarily eats fish, but will take many kinds of invertebrates, including sponges and barnacles.

reproductive biology

Normally broods in small groups, and sites may be either very close to the surf or 1.2–1.9 mi (2–3 km) off. Will use artificial cover, such as buildings, for nesting sites. Young leave the nest after 35–39 days. Clutch size is usually two eggs, deposited under rocks or in deep crevices in cliffs.

conservation status

Population appears stable, but local threats arise from oil spills and commercial fishing.

significance to humans

Some subsistence hunting takes place, but greatly reduced from the level of a century ago.


Puffin

Fratercula arctica

taxonomy

Fratercula arctica Linnaeus, 1758, Norway. Three subspecies.

other common names

English: Atlantic puffin; French: Macareux moine; German: Papageitaucher; Spanish: Frailecillo Atlántico.

physical characteristics

11–14.6 in (28–37 cm); 10.6–21.1 oz (300–600 g). Distinctive large, triangular, mostly yellow and orange bill with bluish gray base; yellowish mouth and tongue. White to grayish face, black

band from forehead to nape, grayish chin. Mostly black upperparts; snowy white underparts; orange to yellowish orange legs and feet.

distribution

The puffin winters at sea in the North Atlantic and breeds on the American and European coasts. Range includes the Baltic Sea and eastern Mediterranean.

habitat

Marine areas near rocky coasts and islands with suitable conditions for digging burrows.

behavior

A strong flier, the puffin is rarely seen near land except during the breeding season. The adults give moaning or bellowing calls. While at sea, puffins have been known to gather in groups with murres and razorbills, although the puffins tend to stay on the periphery of any mixed gatherings.

feeding ecology and diet

Puffins eat mainly fish. The species is known for its habit of packing dozens of small fish crossways in its bill to bring back to its young.

reproductive biology

Couples engage in mating displays in which they tap their prominent bills together. Mating takes place at sea. Puffins nest at the far end of long passageways, which they dig with their beaks and talons into the loose earth covering the rocks. Breeding places may be on crags close to the sea, or several hundred meters removed from the coast. The single egg shell is white and has almost invisible dots. The nestling wears a "furry" down that is dense and soft. Fledglings leave the nest after 36–47 days.

conservation status

Not threatened.

significance to humans

None known.


Dovekie

Plautus alle

taxonomy

Alle alle Linnaeus, 1758, Scotland. Two subspecies.

other common names

English: Little auk; French: Mergule nain; German: Krabbentaucher; Spanish: Mérgulo Atlántico.

physical characteristics

7–8 in (17–20 cm); 4.6–6.7 oz (130–190 g). Small, chubby bird with black head and neck, black upperparts, and white under-parts. Short black bill and blackish gray legs and feet.

distribution

The breeding territory includes all North Atlantic and Arctic coastlines. Outside the breeding season, dovekies are scattered far over the northern Atlantic; some winter amid the drifting ice.

habitat

Rocky coastlines and adjoining seas.

behavior

Silent while at sea as an adult, although the young birds have a high-pitched, peeping call. Adults give vent to a short, high-pitched trill while at breeding grounds.

feeding ecology and diet

Primarily small invertebrates and plankton.

reproductive biology

Greenland and Spitsbergen have colonies of dovekies consisting of thousands, possibly numbering in the hundreds of thousands. Nesting occurs within stretches of shingle or in rock clefts near the ocean, as well as at distances of from four to eight kilometers inland on mountain slopes. The single chick stays in the nest for approximately a month, after which it reaches adult size.

conservation status

Not threatened.

significance to humans

None known.


Marbled murrelet

Brachyramphus marmoratus

taxonomy

Brachyramphus marmoratus Gmelin, 1789, Alaska. Two subspecies.

other common names

English: Atlantic murre, long-billed murrelet; French: Guillemot marbré; German: Marmelalk; Spanish: Mérgulo Jaspeado.

physical characteristics

9.5–10.5 in (24–27 cm); 6.7–9.5 oz (220–270 g). Dark brown crown and upperparts, back feathers tipped in rusty brown; mottled brown and white underparts. Black bill is slender and pointed; flesh-colored legs and feet with dark webs.

distribution

Pacific coast of North America from the Bering Sea to central California, and in similar latitudes on the western side of the Bering Strait.

habitat

Nests in coastal forest, preferring large old-growth areas offering heavy cover, or on rocky ground in the northernmost sections of its range.

behavior

Marbled murrelets spend most of their time at sea, although individuals are occasionally still seen in the forests. Non-breeding birds spend the nights a few miles from shore, moving in closer during the day to feed. Mated pairs are often sighted together at sea throughout the year. Never seen in large flocks.

feeding ecology and diet

Fish and marine invertebrates.

reproductive biology

The murrelets build small, cup-shaped nests, flying to and from them at dawn and dusk. They nest solitarily or, in some areas, in small, loose aggregations. Accordingly, studies of nesting behavior remain limited. Egg is incubated for 27–30 days. After hatching. the chick is fledged and on its own after 27–40 days.

conservation status

Not threatened. There is some concern, especially in the Pacific Northwest, about the effects of increasing nest predation, the reduction in old-forest habitat, and the effects of commercial fishing nets.

significance to humans

None known.


Great auk

Pinguinus impennis

taxonomy

Pinguinus impennis. Formerly known as Alca impennis Linnaeus, 1758.

other common names

English: Garefowl, penguin (the original bird to be so named); French: Grand pingouin; German: Riesenalk; Spanish: Alca Gigante.

physical characteristics

30.5 in (78 cm); 11 lb (5 kg).

distribution

The great auk ranged across the North Atlantic, south of the Arctic Circle as far as New England and the British Isles.

habitat

Rocky coastlines and adjoining seas. Restricted to a few locations where the nesting sites could be reached without flying.

behavior

The great auk was the most dependent of the alcids on the ocean because, unlike its relatives, it had lost the power of flight. Because most observations were made during hunts, little is known about the species' normal behavior. We do know that great auks spent the winters at sea.

feeding ecology and diet

Presumed to have fed mainly on fish.

reproductive biology

Bred in enormous rookeries on a handful of islands: St. Kilda, the Orkneys, islands off Newfoundland, and islands off the southern coast of Iceland. A single pear-shaped egg, which weighed approximately 14 oz (400 g), was laid on rock. Each egg carried a unique pattern of spots and blotches, which probably aided the parents in identifying their own egg.

conservation status

Extinct. By the beginning of the nineteenth century, 300 years of reckless human predation of the easily-captured auks seriously

diminished their numbers. Hunting and egg-collecting continued at an unsustainable rate, exacerbated by a volcanic eruption in 1830 which destroyed one of the bird's last breeding grounds. In 1844, the last two auks known to exist were killed on the island of Eldey, off the southwest coast of Iceland, and their egg was collected and sold.

significance to humans

When the great auk was discovered by mariners, it was looked upon as an excellent source of provisions. The easily-caught birds soon became the focus of an unrestrained industry, in which their feathers were plucked and their bodies were boiled alive for their high oil content. This havoc continued until it became uneconomical due to the lack of auks.


Resources

Books

Fuller, E. The Great Auk. New York: Harry N. Abrams, 1999.

Gaston, A. J., and I. L. Jones. Bird Families of the World: The Auks (Alcidae). Oxford: Oxford University Press, 1998.

Elphick, Chris, John B. Dunning, Jr., and David Allen Sibley. The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf, 2001.

Periodicals

DeSanto, Toni L., and S. Kim Nelson. "Comparative Reproductive Ecology of the Auks (Family Alcidae) with Emphasis on the Marbled Murrelet." USDA Forest Service General Technical Report 152 (1995): 33–47.

Friesen, V. L., A. J. Baker, and J. F. Piatt. "Phylogenetic Relationships Within the Alcidae (Chadriiformes: Aves) Inferred from Total Molecular Evidence." Molecular Biology and Evolution 13, 2 (1996): 359–367.

Hipfner, J. Mark. "Timing of Nest Departure in the Thick-billed Murre and Razorbill: Tests of Ydenberg's Model." Ecology 80 (1999): 587–596.

Hunter, F. M., and I. L. Jones. "The Frequency and Function of Aquatic Courtship and Copulation in Least, Crested, Whiskered, and Parakeet Auklets." The Condor. 101 (1999): 518–528.

Other

IUCN–The World Conservation Union. "Alcidae." The 2000 IUCN Red List of Threatened Species.<http://www.redlist.org>

Matthew A. Bille

Cherie McCollough

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Auks, Puffins, and Murres (Alcidae)

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