![]() We can't blame anyone but ourselves, prairie-bird experts say.Īnd there's no mystery at all about the underlying cause: Land development, primarily for agriculture, has destroyed or degraded vast stretches of the birds' grassland habitat leaving the animals bereft of home and food. They winter mainly in the Sunbelt states, which means their population declines are not due to problems in Latin America, as is the case in part with some forest birds. Moreover, many North American grassland birds are short-distance migrants. ![]() Grasshopper sparrow numbers have plummeted by 96 percent in New York. Illinois, for example, has lost 94 percent of its nesting bobolinks. The disappearance of once-familiar species often is more acute at the state level. Sprague's pipit, which spends the spring months aloft, broadcasting the sound of tinkling sleighbells across northern prairies-down 75 percent. The grasshopper sparrow, whose buzzy vocalizations are above the hearing range of some birdwatchers-down 66 percent. The eastern meadowlark, the original fence-sitter, with its natty sunflower vest and black cravat-down 53 percent. ![]() The bobolink, whose aerial courtship song bubbles like aural champagne over hayfields and old pastures-down 37 percent across its range since 1966. BBS projections for a few grassland species in addition to Henslow's sparrow underscore what Van Remsen, an ornithologist at Louisiana State University, calls "America's most neglected conservation problem." Geological Survey, the BBS depends on 2,000 expert volunteers who, at the peak of every nesting season, count birds along permanent routes in order to track population changes. "These declines are prevalent from the Great Plains eastward across the United States and southern Canada," Peterjohn emphasizes, "and they probably began long before the BBS was conceived."Ī part of the Biological Resources Division of the U.S. In contrast, more than 50 percent of bird species that nest in forests have increased in numbers since 1966, the year of the first BBS counts. He points out that only 10 percent of all grassland species show positive population trends. "Grassland birds exhibit the most consistent, widespread and steepest declines of any habitat group," says Bruce Peterjohn, coordinator of the North American Breeding Bird Survey (BBS). Indeed, Henslow's sparrow serves to dramatize the plight of many of the songbirds that nest in North American grassland habitats, from the shortgrass prairie that rubs against the Rocky Mountains to the few hayfields that still sit atop New England's weathered hills. While the bird is still common enough to make listing unlikely anytime soon, no one doubts that the species, whose continent-wide breeding population is estimated to have declined by 93 percent during the past 30 years, is in serious trouble. ![]() Fish and Wildlife Service biologist in Bloomington, Indiana, whose mission last year was to assess Henslow's sparrow as a possible candidate for the federal Endangered Species List. But to defend its territory, the secretive bird "will get atop a dead plant from last summer and sing its guts out," says Lori Pruitt, a U.S. Henslow's sparrow shyly announces itself with an insectlike hiccup (se-LICK) that would mortify most other sparrows-a clan that includes a couple of nature's finer musicians. Field-guide maven Roger Tory Peterson once remarked, "Were it not for its song, this bird would go almost undetected." At times it behaves more like a mouse than a bird, scurrying through the grass. Henslow's sparrow, in birdwatcher lingo, is an LBJ or little brown job: one of those cryptically colored songbirds that are annoyingly adept at revealing themselves for only a split second, defying identification. From Maine to Colorado, mounting evidence indicates that many grassland bird species, like this Henslow's sparrow, are disappearing as fast as the prairies that support them ![]()
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