Based on the coloration, the Black Tern posted by Catbird8 is a 1st winter juvenile or non-breeding adult. Photo was taken 9-01-09 at Bitter Lake Wildlife Refuge, Chaves Co., N.M. There were two terns alternating in diving down and catching minnows or dragonfly larvae, then flying up to drop and recatch their food. Seemed like they were playing a game. Got a photo of one of the terns chasing a dragonfly.