A black bodied tern that
is easily identifiable in South Dakota, especially in its dark breeding
plumage. The bird at the right is an adult, breeding plumaged bird, with a
black body and silvery-gray wings. Non-breeding birds are much lighter in
coloration, with white underparts and head, gray wings, and a small amount of
black on the back of the head. Black Terns lead a unique life, nesting on
freshwater marshes in the interior of North America, while wintering at sea
around South America. They gracefully pluck food items in flight from the
surface of the water. They will also chase flying insects, doing much of
their foraging over aquatic habitats, but they will also forage over nearby
terrestrial habitats. As with some other gull and tern species, they will
sometimes follow farm equipment to pursue insects that are stirred up.
Habitat: Marshes, ponds, lakes, flooded fields
Diet: Mostly insects and fish, also
frogs and tadpoles, earthworms, and crustaceans.
Behavior: Forages while in flight, dipping down to
the water's surface to grab food, or also by catching insects in mid-air.
Nesting: June. They breed in small colonies,
sometimes associated with other species such as the
Forster's Tern. The nest is a mound
of wetland vegetation with a slight depression on the top. The female lays
between 2 and 4 eggs, and both parents help to incubate them. When the
eggs hatch, both parents help tend to the yong. The young fledge as soon
as 3 weeks after hatching, but parents typically feed the young for another few
weeks after fledging.
Song: Harsh kik-kik-kik-kik.
Migration: Summers in much of the northern Great
Plains, the Great Lakes, and western U.S., as well as southern Canada. Winters along northern coasts of South America.
Similar Species: Generally distinctive compared to
other tern species in North America. Very similar to the
White-winged Tern, a Eurasian species
that is a rare vagrant to North America.
Conservation Status: Populations have declined sharply in the past 40 years, likely
due to drainage of wetlands required for nesting. Farm chemical runoff is
another possible reason. Despite population declines, they are still found
over a wide geographic area, and are common in some areas.
The IUCN lists the
Black Tern as a species of "Least Concern".
Cornell University's "All About Birds - Black Tern"
-- Black Tern
Photo Information: May 14th, 2010 - Lake Whitewood in
South Dakota -- Terry Sohl
Additional Photos: Click on the image chips or
text links below for additional, higher-resolution Black Tern photos.