Thursday, May 3, 2012

Green Jay

The suite of Texas bird specialties we found at Laguna Atascosa National Wildlife Refuge surprised me. I thought you had to be right on the Rio Grande to see them. The first of these birds was the Green Jay, found just north of the Rio Grande south through South America to Peru and Bolivia. As I ran about in chasing jays, Erika took these photographs.

South Texas Green Jay flocks contain related nonbreeding birds. Flocks contain a breeding pair, the current year's young, and jays from the previous year. What is unusual is that these nonbreeders do not help at the nests, as do many other birds. They do, however, provide territorial defense for the breeding pair. The birds from the previous year are run out of the flock when the current year's nestlings fledge. Oddly, Green Jays in Colombia do help their parents raise the current year's young. This difference may be the result of less abundant food resources in Colombia (Gayou 1995).

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