Auks, Puffins, and Murres: Alcidae

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AUKS, PUFFINS, AND MURRES: Alcidae

COMMON MURRE (Uria aalge): SPECIES ACCOUNTS
PUFFIN (Fratercula arctica): SPECIES ACCOUNTS
GREAT AUK (Pinguinus impennis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Alcids, species in the Alcidae family, range from 6 to 17 inches (12 to 45 centimeters) in length and from 0.17 to 2.4 pounds (0.4 to 1.1 kilograms) in weight. They have narrow, short wings and short tails. Their toes are webbed. Alcids are primarily black, white, and gray in color, although some species have brown feathers during parts of the year. Males and females are similar in coloration. These birds also have a striking upright posture, one of the physical features that makes them well-suited to diving and "flying" underwater. All species are also able to fly in the air, although many need a running start to become airborne.

Bill shape varies a great deal in the group. The razorbill has a long, sharp bill. Puffins have deep bills that are laterally compressed, flattened left to right. The dovekie has a short, pointed bill. Guillemots have straight bills. The parakeet auklet has an unusual bill in which the lower half turns upward at the tip. This bill helps it catch its primary prey, jellyfish.

GEOGRAPHIC RANGE

Auks and their relatives are found in the Northern Hemisphere, in oceanic habitats in the Arctic, North Atlantic, and North Pacific.

HABITAT

Auks and their relatives are found in cold ocean waters. They breed in seashore areas such as shorelines, seaside cliffs, and, in some species, coastal forests.

DIET

Large members of the auk family, including murres, razorbills, puffins, and guillemots, eat primarily small fish. They sometimes also eat invertebrates, animals without backbones, such as squid and crustaceans. Smaller members of the family, such as the dovekie, eat primarily marine invertebrates such as crustaceans and mollusks. Many species fly far out over the ocean in search of food. Auks and their relatives capture food by resting on the surface of the water and then diving down after prey, propelling themselves forward with their wings.

BEHAVIOR AND REPRODUCTION

Auks are capable, but not strong, fliers. Most species require a lengthy running start over water before they are able to take to the air. However, all species are very good swimmers and divers. Auks and their relatives use their wings to propel themselves through the water. Their webbed feet, which are stretched out during swimming, act as a rudder and help them change or maintain direction. Some species have been known to reach depths as great as 600 feet (183 meters).

Auks and their relatives are monogamous (muh-NAH-guh-mus), a single male mates with a single female. However, the same mates are not necessarily kept from one breeding season to the next. Many individuals do, however, return to the same nesting site year after year. Eight of the twenty-three auk species mate on the open ocean. Both parents help incubate, or sit on, eggs, and both help feed and protect the young once they hatch. In most species, the female lays only one large egg which may represent 10 to 20 percent of the female's total weight. Chicks are covered with dense down at birth and are able to see. In several species, chicks leave the nest after two or three weeks and go with their fathers to live on the open ocean until they become independent.

MATING AT SEA

Eight species in the auk family mate at sea, an unusual breeding strategy. There are several possible reasons why this may be advantageous. Mating at sea may help auks avoid land predators. It may help male auks avoid competition and interference from other males of the same species. Finally, some biologists believe that female auks may use sea mating to figure out which males are healthiest and strongest, and would therefore make the best mates.

AUKS, PUFFINS, MURRES, AND PEOPLE

Several species are hunted in large numbers in parts of Greenland, Canada, and Alaska.

CONSERVATION STATUS

The great auk became Extinct, died out, around 1844 c.e. due to hunting by humans. Several currently existing auk species are considered Vulnerable, facing a high risk of extinction in the wild in the medium-term future, including Xantus's murrelet and the marbled murrelet. Xantus's murrelets are threatened by habitat damage in their breeding grounds in Baja California and on islands off the coast of Southern California. They have also been affected by predators associated with humans such as cats and rats. Marbled murrelets, which occur in areas of the United States, have been affected primarily by habitat loss. Both species are listed as Threatened by the U.S. Fish and Wildlife Service. Other members of the auk family are affected by habitat destruction and damage as well as by oil spills and fishing nets.

COMMON MURRE (Uria aalge): SPECIES ACCOUNTS

Physical characteristics: Common murres have black-brown heads and backs. Their bellies are white. They have long, slender, pointed black bills.

Geographic range: Common murres are found from California to Alaska on the western coast of North America. On the eastern coast of North America they can be seen from New England to Labrador. They are also range from Siberia to Japan and Korea.

Habitat: Common murres inhabit rocky seashore areas during the breeding season, but spend most of the rest of the time on the open ocean.

Diet: Common murres eat primarily fish. They also eat some marine invertebrates.

Behavior and reproduction: Common murres are fast, able fliers often found in large flocks. Their calls sound like the purr of a cat. During the breeding season, common murres nest in large colonies, which may include other species of birds. The female lays a single egg on bare rock. Parents are able to recognize their egg visually by its markings, and can find their own egg if it happens to roll away. Eggs hatch after thirty-two to thirty-five days. The chick leaves the nest after twenty to twenty-two days. Chicks follow their fathers to open ocean and are cared for until they become independent.

Common murres and people: Common murres are hunted in large numbers in Newfoundland.

Conservation status: Common murres are not considered threatened at this time. However, populations have been affected by habitat disturbance and hunting. ∎

PUFFIN (Fratercula arctica): SPECIES ACCOUNTS

Physical characteristics: Puffins have a very distinctive large, yellow and orange bill with a blue-gray base. Their faces are white to gray with a thick black band from the forehead back. Their backs are black and their bellies white. Their legs and feet are orange.

Geographic range: Puffins breed on seashore areas of North America and Europe. They spend the winter in the waters of the North Atlantic.

Habitat: Puffins inhabit rocky seashore areas and islands during the breeding season. They spend the winter at sea.

Diet: Puffins primarily eat fish. When feeding young, adults are known to carry dozens of fish back at a time in their large bills.

Behavior and reproduction: Puffins are strong fliers and spend most of their time at sea, except during the breeding season. At sea, puffins may be found in flocks with other species such as murres and razorbills. Puffins also mate at sea. Courtship, behavior that leads to mating, involves the male and female tapping their bills together. Puffins build nests at the end of long burrows which they dig in the ground. The female lays a single egg. The chick hatches with a thick coat of down and is able to leave the nest after thirty-six to forty-seven days.

Puffins and people: No significant interactions between puffins and people are known.

Conservation status: Puffins are not considered threatened at this time. ∎

GREAT AUK (Pinguinus impennis): SPECIES ACCOUNTS

Physical characteristics: Great auks were the largest members of the auk family, measuring 30.5 inches (78 centimeters) in length and 11 pounds (5 kilograms) in weight. They had black heads and backs, black wings, black feet, and white bellies.

Geographic range: Great auks were once found in the North Atlantic, between the Arctic Circle, New England, and the British Isles.

Habitat: Great auks were found in rocky seashore areas as well as in adjacent open ocean.

Diet: Great auks ate mainly fish.

Behavior and reproduction: Great auks were unable to fly. They spent the winter primarily at sea. During the breeding season, great auks were found in huge colonies on a small number of islands. Females laid a single egg on bare rock. Eggs had unique markings which likely allowed parents to recognize their own egg.

Great auks and people: Great auks were driven to extinction by human hunting. Because they were unable to fly and gathered in large numbers during the breeding season, they were extremely easy to hunt. Their feathers were collected and their bodies were boiled to extract valuable oil. Their eggs were also collected.

Conservation status: Great auks went extinct sometime around 1844 c.e. due to human hunting and egg collection. ∎