Common Murres nest on rocky cliffs and headlands at the edge of the ocean. During the breeding season, they forage at sea, normally over waters deeper than 100 feet and well away from land, at places where warm and cool currents meet and concentrate their prey, mostly fish. They forage closer to shore for much of the nonbreeding season, often coming quite close to land. When not breeding, they remain on the ocean rather than coming ashore to rest or roost. Where their range overlaps with the Thick-billed Murre, that species tends to forage over deeper waters, farther from shore, than Common.Back to top
Common Murres eat mostly fish, along with squid, octopus, and—especially in the nonbreeding season—small marine crustaceans such as krill and amphipods. In the Pacific, rockfish (genus Sebastes), pollock, arctic cod, saffron cod, tom cod, surfperch, sandlance, sculpin, hake, greenling, capelin, herring, smelt, anchovy, and sardine are common prey items. In the Atlantic, they take capelin, sandlance, shad, menhaden, flounder, lanternfish, and Atlantic cod. Murres forage alone or in flocks, often with other seabird species. They catch prey in the bill during deep dives. Murres “fly” underwater, using their wings for propulsion and steering. Dives as deep as 591 feet have been recorded, but murres take most prey at depths of 66–164 feet. They usually consume their prey while still underwater (except when bringing fish back to feed young).Back to top
Murres lay their single egg directly on a cliff ledge or similar site above the ocean, sometimes in a hidden crevice or under a boulder.
Murres don't build a nest, but adults sometimes arrange small pebbles around the egg, and these become cemented by guano, which perhaps helps the egg to stay on the cliff.
|Clutch Size:||1 egg|
|Number of Broods:||1 brood|
|Incubation Period:||26-39 days|
|Egg Description:||Very pointed at one end. Color variable, ranging from white to tan without markings, to dark green or turquoise with extensive black spots and scrawls.|
|Condition at Hatching:||Covered in down, able to stand within one day.|
Common Murres are monogamous and often stay partnered for several years consecutively. Before nesting, groups of murres near the nesting cliffs sometime display. A “water dance” display features birds chasing one another, pattering over the sea but not flying. In another display known as “joy flight,” they fly in circles, sometimes quite high in the air. Pairs begin, and maintain, their bonds with a greeting ritual, in which both birds spar with bills, bow, and preen one another, usually while calling.
Males guard females intensely before egg-laying, chasing off rivals with sudden lunges and bill jabs. Although murres do not have true territories, they defend the immediate area where the egg or chick is present. Pairs use the same precise sites for nesting for consecutive years, and young murres usually return to the same cliff where they hatched. Both parents feed the single chick. The male takes the chick to sea and teaches it how to capture prey.Back to top
In North America, Pacific populations of Common Murre have declined in recent decades, but Atlantic populations appear to be increasing slightly in some areas. Partners in Flight estimates the global breeding population at 12 million individuals, with about 7.4 million breeding in the U.S. and Canada. The group rates the species an 11 out of 20 on the Continental Concern Score, indicating a relatively low level of conservation concern. Despite the current large population, global climate change is forecast to modify ocean temperatures and currents and thus the distribution and availability of prey species. Such changes could have significant, even catastrophic effects on murres and other seabirds. They are also vulnerable to pollution from oil spills, drowning in gill-netting operations, overfishing of prey species, and the introduction of mammalian predators such as foxes. Murres are hunted for food, with around 100,000 taken annually in Canada in regulated hunting, as well as additional hunting in Greenland and Faeroe Islands. Historically, eggs were taken for food by the hundreds of thousands each year.Back to top
Ainley, David G., David N. Nettleship, Harry R. Carter and Anne E. Storey. (2002). Common Murre (Uria aalge), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.