During the summer nesting season, songbirds can be heard trilling their hearts out as they go about the romantic business of attracting a mate and setting up housekeeping. If you`d like to be able to translate those twitters and recognize a bird just by its song, a new audiocassette, ”Backyard Bird Song” (Houghton Mifflin, $19.95), can help.
The one-hour cassette, which comes in a vinyl case and is accompanied by a 32-page illustrated booklet, features the songs and calls of 28 common back- yard birds, including the house finch, northern cardinal, mourning dove, American crow, house sparrow, American robin, red-winged blackbird, European starling and tufted titmouse. The cassette also includes the vocalizations of squirrels and chipmunks, whose sounds sometimes are mistaken for birdcalls by beginning birders.
As naturalist Dick Walton explains in his narrative, bird sounds are divided into songs and calls. Generally, adult males do the singing, though some females also sing. They sing to attract and woo a mate and announce to a rival that the territory is occupied.
Bird calls generally are shorter and less melodic than songs and are given year-round by birds of both sexes and all ages. Calls often are given as alarms or to impart other nonsexual information.
”A bird`s song can tell us a lot about what is going on in his or her life,” Walton says.
”Backyard Bird Song” is the latest in the series of Peterson Field Guides, which are co-sponsored by the National Audubon Society, the National Wildlife Federation and the Roger Tory Peterson Institute.
