Interior Least Tern: Nest, Eggs, Chicks

Nests:

  • nest in colonies
  • place nests on the ground in bare sand
  • lay 2 - 3 eggs in a small cup-like depression
  • produce one per season
  • may re-nest up to three times if the nest is lost early in the season
  • do not nest until their 3rd summer
  • can live 20 years or more (record is 24 years)

Eggs:

  • Well camouflaged (pale to tan with dark spots but coloration is highly variable)
  • Take about 21 days to hatch
  • A little larger than a quarter

Chicks:

  • Coloration varies from grayish-brown to yellow to nearly reddish or sandy-brown with white undersides and tiny dark spots on head and back
  • Semiprecocial which describes young that have open eyes, down, and are mobile at hatch but don't leave the nest right after hatching
  • Typically leave the nest within two days of hatching
  • Flightless and depend on parents for food (small fish) and protection until about 21 days

Defensive Behavior

  • Adults are aggressive
  • Adults defend nest and chicks by mobbing, dive bombing, and defecating on intruders
  • Chicks will usually lay flat on the sand pretending to be a rock or they will hide under a plant, rock, or piece of driftwood

Nest and Chick Predators:

  • American Kestrels (Falco sparverius)
  • Great Blue Herons (Ardea herodias)
  • American Crows (Corvus brachyrhynchos)
  • Owls
  • Skunks
  • Raccoons
  • Foxes
  • Coyotes
  • Cats
  • Dogs
  • Humans

 

Chick hiding under a tree branch
Chick hiding under a tree branch