Caspian Tern

Caspian Tern (Sterna caspia)
Species Code: STCA

Description: The Caspian Tern can be identified from other terns by the large bright red-orange bill. As large as a big gull, the Caspian Tern is the largest tern in the world. It has long light-gray wings, a white body and dark cap. The legs and feet are black. Males and females look alike.

Photo courtesy of Natures Pics.

Calls: The call is a raspy "kowk." Juvenile begging call is a high pitched whistling; heard frequently during migration and in winter.
Listen to calls of this species »

Range / Habitat: The Caspian Tern is one of the most widespread tern species in the world, occurring on every continent except Antarctica. Breeds in scattered locations across North America, along Pacific Coast, in central Canada, around the Great Lakes, in west-central United States, along the Gulf Coast, and along the Atlantic Coast.

The Caspian Tern breeds in wide variety of habitats along water, such as salt marshes, barrier islands, dredge spoil islands, freshwater lake islands, and river islands. During migration and winter they are found along coastlines, large rivers and lakes. Roosts on islands and isolated spits.

This species primarily occurs on freshwater bodies in eastern Washington, nesting on sandy islands.

Diet: Caspian Terns primarily eats fish. Occasionally hunts for crayfish and insects. In the Columbia River estuary, where most of Washington's population breeds, salmonid smolts are a major prey item.

Behavior: The Caspian Tern flies over water with the bill pointing down. When they spot a fish swimming, they hover, then plunge into the water to catch their prey.

Caspian Terns are less gregarious than other terns, nesting in smaller colonies. They aggressively defends its breeding colony.

Migration: Some Caspian Terns in Washington are medium-distance migrants, wintering on the coast of California, while others travel greater distances, wintering as far south as Colombia and Venezuela. (BirdWeb)

Nesting: Caspian Terns nest in colonies in areas with no vegetation, often on islands. Both parents help build the nest, which is located on the ground. The nest can range from a scrape in the sand to a small depression lined with a rim of vegetation and shells.

The female lays 1 to 3 eggs which are incubated by both parents for about three weeks. A few days after hatching, the young may leave the nest but stay nearby, or they may remain at the nest until they are ready to fly. Both parents help feed the young during the long period of development. The young first fly about a month after hatching. They tend to stay near the adults so they can be fed for many more months.

Did you know?

• The Caspian Tern aggressively defends its breeding colony.
• The young rely on the parents to feed them for several months after hatching.
• Average life span of Caspian Terns is estimated to be 12 years.

Caspian Tern on a beach

More information:
All About Birds: Caspian Tern
BirdWeb: Caspian Tern
Sound to Sage: Caspian Tern