black tern, credit: Ingrid Taylar CC BY 2.0

Special Concern Provincially, Not Listed Nationally


• Small, boldly marked tern with black head and underparts; forked tail;
straight pointed bill; slender shape; long, narrow wings
• Eats insects
• Builds floating nests in loose colonies in shallow marshes, especially in cattails


• Breeds in temperate regions of Europe and North America, and in Canada from British Columbia to New Brunswick
• Scattered throughout Ontario, breeding mainly in marshes along the Great Lakes. There are also confirmed breeding sites scattered throughout northern Ontario, as far north as Dryden


• Habitat loss (wetlands)
• Water pollution
• Human disturbance at nesting colonies (especially boat traffic)
• Invasive species
• Climate change


• Federally protected under the Migratory Birds Convention Act, 1994
• Not protected under the Endangered Species Act, 2007


The black tern has experienced a continuous decline across its global range since the 1950s, with a 61 percent decline between 1966 and 1996 in North America.