And then there were the river dolphins, gray ones and pink, and many, many birds. By category I can name birds that were identified to us: kingfishers, wading birds, vultures, hawks and kites, ibis, herons and egrets, flycatchers, swallows and swifts, tanagers and honeycreepers, orioles and blackbirds, parrots, macaws and parakeets, trogons and hummingbirds, nighthawks and nightjars, toucans and barbets, woodpeckers and woodcreepers. I must admit I didn't see many of these birds very well, half the time asking where? where? but when I heard our guide call out ''There's a black-fronted nunbird,'' I really tried to find it. My favorite was the ''Horned Screamer.''