Black Tern

Chilidonias niger

Black Tern with chicks. Photo credit: Dana Cofell


  • COSEWIC – Not at risk.
  • COSSARO – Special Concern


  • Small, 25 cm, boldly marked tern with black head, chest and belly.
  • Wings slate grey with black wing tips.
  • Tail slate grey with white underneath.
  • Bill is black. Legs dark red
  • Sexes appear similar.

Habits and Reproduction:  

  • Floating nests in loose colonies in shallow mainly cattail marshes
  • Monogamous and breeds at 2 yrs of age.
  • Typically 2-3 eggs are laid late May to early July.
  • Migrate to north coast of South America and return early May.
  • Eats mainly insects picked off while hovering above the water surface and also other aquatic invertebrates and small fish.


  • Mainly found on the Great Lakes in coastal marshes.


  • Wetland loss, water pollution, and disturbance of nesting areas by boat traffic.

Conservation Actions:

Thanks to the official sponsors of the Ontario Breeding Bird Atlas (Bird Studies Canada, Canadian Wildlife Service, Federation of Ontario Naturalists, Ontario Field Ornithologists, and Ontario Ministry of Natural Resources) for supplying Atlas data, and to the thousands of volunteer participants who gathered data for the project.