Common murre(Uria aalge)
Habitat and Distribution: Found along the Pacific Coast from the Arctic Ocean above Norway down to San Francisco, California and also along the shores of eastern Canada.
Size: 15-18 inches tall; 800-1125 grams (about 2 pounds)
Predators: Eggs and chicks are prey to gulls, ravens, and eagles
Life Span: 20-25 years
Reproduction: Their nesting colonies, with 28-34 birds per square meter, are the most densely packed of any bird. Rather than building nests, females lay a single egg on bare rock ledges, under rocks, or on the ground. Eggs are usually laid between March and July and they are pear-shaped, which prevents tipping and allows them to roll in circles instead of rolling off the cliff's edge. Incubation is 4-5 weeks and both male and female incubate the egg and feed the chick after it hatches. The chick leaves the nest with a parent, usually the male, at about 2-3 weeks of age.Behavior: While nesting, common murres may live on rock pillars near the coast known as “sea stacks” or on rocky cliffs on islands with little vegetation. The rest of the year, they are out at sea. They are diving marine birds and forage primarily during the day. One parent stays behind with the chick while the other is foraging.
The main threats to common murres are oil spills, over-fishing, and fishing nets. They are also highly sensitive to human disturbance. When startled by planes, boats, or humans on foot, they may accidentally crack or break their eggs.
Did you know?
- Nests are located so close together that incubating adults actually touch their neighbors on both sides.
- When common murres dive underwater, they use their wings to swim.
- They have a variety of vocalizations, including purrs, croaks, growls, and moans.