Forster's Tern

Sterna forsteri

Forster’s Terns reside on Swanquarter National Wildlife Refuge in the fall and winter. They occupy the refuge’s brackish marshes, water bodies within the marshes, and the shorelines of the sound. They eat small fish, shrimp, and crabs. They plunge into water from flight; may hover briefly before plunging.


Forster’s terns are medium-sized terns. They have comma-shaped black ear patch in winter plumage is distinctive, but some other plumages are very confusing. They are white with black cap, have long tails that is deeply forked. Their wings are very white in most plumages. Their legs are orange and relatively long. Immature Forster’s Terns resemble the winter adults, but has even darker primary feathers. They may have dark center and end feathers. Forster’s Terns are 13 to 14 inches long and have weigh 4 to 7 ounces.


Forster’s Terns nest in the Upper Midwest and south-central Canada. They breed in marshes, generally with lots of open water and large stands of island-like vegetation. Their nests vary from unlined scrape in mud or sand, to elaborate raft of floating vegetation, or on top of a muskrat lodge. The nests are typically placed in clumps of marsh vegetation close to open water.

Facts About Forster's Tern

  • Eat small fish, shrimp and crabs.
  • Seasonal visitors in Fall and Winter.
  • Comma shaped black ear patch in winter plumage.