Forster's Tern Life History


Habitat Marshes

  • Breeds in marshes, generally with lots of open water and large stands of island-like vegetation.
  • Winters in marshes, coastal beaches, lakes, and rivers.
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Food FishSmall fish and arthropods.Back to top


Nest Placement

Nest Floating

Nest Description

Varies from unlined scrape in mud or sand, to elaborate raft of floating vegetation, or on top of a muskrat lodge. Typically placed in clumps of marsh vegetation close to open water.

Nesting Facts
Clutch Size:1-6 eggs
Egg Description:Olive to buff, marked with numerous small spots and blotches of dark brown, often concentrated around the larger end.
Condition at Hatching:Downy, eyes open, able to walk but stays in nest.
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Behavior Aerial Dive (water)Plunges into water from flight; may hover briefly before plunging.Back to top


Conservation Low ConcernForster's Tern appear to have experienced declines between 1966 and 2015 according to the North American Breeding Bird Survey, but there is not enough data to estimate numbers with certainty. The North American Waterbird Conservation Plan estimates between 47,000-51,500 continental breeding birds, and lists it as a Species of Moderate Concern. Forster's Tern ranks an 11 out of 20 on the Continental Concern Score. The species is not on the 2016 State of North America's Birds Watch List, but is of special concern in some states due to declines resulting from the loss of wetland habitat.Back to top


Kushlan, J. A., M. J. Steinkamp, K. C. Parsons, J. Capp, M. A. Cruz, M. Coulter, I. Davidson, L. Dickson, N. Edelson, R. Elliott, R. M. Erwin, S. Hatch, S. Kress, R. Milko, S. Miller, K. Mills, R. Paul, R. Phillips, J. E. Saliva, W. Sydeman, J. Trapp, J. Wheeler and K. Wohl (2002). Waterbird conservation for the Americas: The North American waterbird conservation plan, version 1. Washington, DC, USA. 

Lutmerding, J. A. and A. S. Love. Longevity records of North American birds. Version 2015.2. Patuxent Wildlife Research Center, Bird Banding Laboratory 2015.

McNicholl, Martin K., Peter E. Lowther and John A. Hall. 2001. Forster's Tern (Sterna forsteri), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.

Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski, Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2017). The North American Breeding Bird Survey, Results and Analysis 1966–2015. Version 2.07.2017. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.

Sibley, D. A. (2014). The Sibley guide to birds, second edition. Alfred A. Knopf, New York, USA.

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