General
Arctic Tern: Medium-sized slim tern with gray upperparts, black cap, white rump and throat and pale gray underparts. Tail is deeply forked and white with dark edges on outer feathers. Bill is dark red, rarely tipped with black. Legs and feet are red. Sexes are similar. Winter adult has dark red or black bill, black cap restricted to back of head, white forehead and underparts and black legs and feet. Juvenile has a white forehead in front of a partial black cap, black bill, red legs and feet and white and gray mottled upperparts.
Range and Habitat
Arctic Tern: Breeds on arctic tundra from Aleutians, northern Alaska & across northern Canada and south to northern British Columbia, northern Manitoba, Quebec, and Maine. Declining breeder in Massachusetts. Winters in Antarctica. Furthest migration of all birds: up to 22,000 miles round trip. They see more daylight than any creature since they are in both Southern and Northern Hemispheres during periods of longest days.
Breeding and Nesting
Arctic Tern: These terns often return to the same area they were hatched to breed. They are ground-nesting species. One to three buff to pale olive eggs with black and brown blotches are laid on bare rocks, often lined with nothing more than a few pebbles. The color and markings of the eggs are excellent camouflage. Both parents incubate the eggs for about 24 days and rear the young together.
Foraging and Feeding
Arctic Tern: These terns primarily eat small fish, crustaceans, insect adults and aquatic larvae, invertebrates, shrimp and krill. They frequently feed offshore over predatory fish that drive prey to the surface. They forage by swooping down and catching prey at the water surface. Inland, they principally forage at streams, rivers and lakes.
Vocalization
Arctic Tern: Call is a raspy "tr-tee-ar."
Similar Species
Aleutian Tern: Arctic and Caspian terns are larger and lack white forehead.