Friday, May 17, 2019

Caspian Tern

During a 7 May 2019 stroll at the Nisqually National Wildlife Refuge, we spied a flock of about a dozen Caspian Terns. These terns are found almost around the world. In North America, they breed along our coasts, and in the Midwest. They winter from our southern coasts to Venezuela and Columbia.

Caspian Terns dive for fish. Like the tern in the bottom photos, they also court with fish. Males carry their prey over a tern colony. A male then lands near the other birds, often near a female at the edge of the flock. Still carrying the fish, the male bows. The female might ignore the male, try to steal the fish, or initiate copulation. She may beg for the fish, which the male is often hesitant to give her. If the male is successful, he may feed the fish to the female. Copulation oftren follows courtship feeding. Males may make several different colony sites a day until her acquires a mate (Cuthbert and Wiens 1999)

No comments:

Post a Comment