Here is another cover from USA badly postmarked. The bird stamps from left to right were issued in 1969, 1971, and 1994. The last two were a joint issue with China. We already talked about California Condor so I will focus on the other three stamps.
Northern Flicker (Colaptes auratus): It is a member of the woodpecker family. This migratory bird lives in North and Central America in woodlands. It has three subspecies of which one is unfortunately extinct. It feeds on insects, fruit, berries, nuts and seeds.

Whooping Crane (Grus americana): It lives in North America and it is an endangered species. They feed on crustaceans, mollusks, aquatic insects, fish, frogs, snails, small rodents, berries etc.

Black-Necked Crane (Grus nigricollis): It lives in Asia and it is an endangered species. Like all cranes, they are too omnivorous.