Monday, August 15, 2022

Gull-Billed Tern

The gull-billed tern, in summer, has a black cap, bill and legs, white underparts and gray upperparts. In winter it loses the black cap and gets a dark patch through its eye, kind of like Bonaparte's gull. It is a cool looking bird. 

It has a weird, splotchy distribution: only along the coasts of North America; a big splotch of mid-south Argentina; a long stripe through eastern Africa (perhaps the Nile), and a dashed strip through West Africa; and a big chunk of west/central Asia. We saw it in the Tagus Estuary of western Portugal which is not shown on the range map as part of it's territory. 
Gull-billed tern range from Wikipedia. Orange is breeding and blue is non-breeding. 

2 comments:

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  2. The name is interesting. It is somehow a genetic cross between two species?

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