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).