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Common Tern

Sterna hirundo

Length: 13 to 16 inches Wingspan: 30 to 32 inches Seasonality: Migrant / Summer
ID Keys: Long forked tail, black cap (breeding season), reddish slim bill, contrasting darker gray on upperside of wing-tip.

Common Tern - Sterna hirundo The Common Tern are so-named because they are the most common tern in much of the Northeastern U.S.  In much of the inland portion of the continent, they are outnumbered by the very similar Forster's Tern.  They were hunted to near extinction in the 1800s for their "fashionable" feathers, but rebounded in the 1900s.  As larger predatory gulls have learned to co-exist with human populations and thrive on their refuse, the Common Tern has once again suffered population declines from predation in the latter half of the twentieth century.

Habitat: Can be found in a wide range of aquatic habitats during the summer breeding months, including coastal and inland waters.  Primarily winters along coastlines in tropical regions of South America.

Diet: Primarily feeds on small fish.  Also will eat shrimp and other crustaceans, small mollusks, insects, marine worms, squid, and leeches.  

Behavior: Primarily feeds by hovering over water to spot prey, and then plunging below the surface to catch it.  Courtship often consists of high paired flights over breeding colonies.

Nesting: June

Song: Has a harsh long keee-arrrrrr, as well as other notes.  Click to listen to Common Tern song.

Migration: Breeds in much of southern Canada and the northern tier of U.S. states.  Most overwinter along the coast of South America, with only small numbers overwintering on the coasts of Central and North America.

Interactive eBird Map: Click here to access an interactive eBird map of Common Tern sightings

Similar Species: Forster's Tern, Arctic Tern

Conservation Status: Numbers are much lower than historical levels due to hunting in the 1800s.  Numbers rebounded in the first part of the 1900s, but the expansion in range and numbers of the large predatory gulls in the latter half of the century again caused reductions in their numbers.  

Further Information: 1) Patuxent Bird Identification InfoCenter, Common Tern

2) Cornell University's "All About Birds - Common Tern"

3) -- Common Tern

Photo Information: July 18th, 2004 -- Below Oahe Dam -- Terry Sohl

Additional Photos: Click on the image chips or text links below for additional, higher-resolution Common Tern photos.


Click on the map below for a higher-resolution view
Common Tern - Range Map
South Dakota Status: Uncommon migrant in the east and along the Missouri River.  Rare migrant in the western half of the state.  Uncommon summer resident in the northeast.

Additional Common Tern Photos
Click for a higher-resolution version of these photos
 Common Tern - Sterna hirundoCommon Tern - Sterna hirundo