It spends most of its time at sea, only coming to land to breed on rocky cliff shores or islands.

They are highly mobile underwater using their wings to 'fly' through the water column, where they typically dive to depths of 30–60 m (100–195 ft).

They make no nest; their single egg is incubated between the adult's feet on a bare rock ledge on a cliff face.

Some 20 days after hatching, the chick leaves its nesting ledge and heads for the sea, unable to fly, but gliding for some distance with fluttering wings, accompanied by its male parent.

Adult birds balance their energetic budgets during the winter by reducing the time that they spend flying and are able to forage nocturnally.

The common murre was formally described and illustrated in 1763 by the Danish bishop Erik Pontoppidan under the binomial name Colymbus aalge.

[4] The species is now placed together with the thick-billed murre in the genus Uria that was described in 1760 by the French zoologist Mathurin Jacques Brisson.

French: Guillaume, but ultimately onomatopoeic from the loud, high-pitched "will, willem" begging calls of the newly fledged young of the common guillemot.

[12] The American name murre, also known from England (particularly Cornwall) from the 17th century, is by contrast, onomatopoeic of the growling call of adult common guillemots.

[16] In breeding plumage, the nominate subspecies U. a. aalge is black on the head, back and wings, and has white underparts.

[19] They jump from the breeding cliffs at 20–21 days old, long before being fully fledged, and are cared for by the male parent at sea.

[26] In general, potential threats include excessive hunting (legal in Newfoundland), pollution and oil spills.

Cape Meares, Oregon is home to one of the most populous colonies of nesting common murres on the North American continent.

UK populations are generally distributed near their breeding colonies year-round, but have been found to make long-distance migrations as far north as the Barents Sea.

In the black-legged kittiwake (which shares this winter habit) resting metabolism is 40% higher on water than it is in air.

[29] A marine heat wave killed off half the murre population in Alaska between 2014 and 2016, and as of 2024 the species has yet to recover.

Capelin and sand lances are favourite food, but what the main prey is at any one time depends much on what is available in quantity.

[32] The common murre nests in densely packed colonies (known as "loomeries"[citation needed]), with up to twenty pairs occupying one square metre at peak season.

The male points its head vertically and makes croaking and growling noises to attract the females.

When laying, she assumes a "phoenix-like" posture: her body raised upright on vertical tarsi; wings half outstretched.

[44] Colours include white, green, blue or brown with spots or speckles in black or lilac.

[43] Both parents incubate the egg using a single, centrally located brood patch for the 28 to 34 days to hatching in shifts of 1–38 hours.

However this rapid growth comes at a cost, first chicks have larger fat reserves and can withstand temporary shortages of food.

[citation needed] Once the young chick has left the nest, the male is in close attendance for up to two months.

[49] Major oil spills double the winter mortality of breeding adults but appear to have little effect on birds less than three years old.

[50] Nesting common murres are prone to two main sources of recreational disturbance: rock-climbing and birdwatching.

Sea cliffs are a paradise for climbers as well as birds; a small island like Lundy has over 1000 described climbing routes.

The provisioning time relates to the distance of the feeding areas from the colony and the numbers of available fish.

Eggers from San Francisco took almost half a million eggs a year from the Farallon Islands in the mid-19th century to feed the growing city.

[55] A 2024 study[56] in the journal Science has reported that an extreme marine heatwave has killed approximately half of Alaska’s Common murre.