The sparrows' extinction would likely be the nation's first loss of a bird since the late 1980s, according to the Cornell Lab of Ornithology. That's when the dusky seaside sparrow, also a Florida native, slipped out of existence. The threat of losing another bird unique to Florida alarms scientists, who also worry that the grasshopper sparrow's rapid decline might be symptomatic of profound problems with the state's dwindling prairie environment.

"This seems to be the most highly imperiled bird in all of mainland North America," said Reed Noss, a biology professor at the University of Central Florida. "At the present rate of decline, it's going to be extinct in as few as three years and, unbelievably, we don't know why."

The small bird is firmly adapted to giant expanses of "dry prairie." Florida had more than 1.2 million acres of that treeless terrain, but 90 percent of it was turned into inhospitable cattle pasture by the end of the 20th century.

The bit that still remains constitutes one the state's last, old-growth landscapes, an ecosystem carpeted with an astounding variety of grasses and flowering plants; pasture, in contrast, is often dominated by planted Bahia grass.

Scientists have no doubt that the extensive loss of habitat caused most of the bird's decline. As for what's behind the recent population dive, they think invading fire ants are eating chicks and increasingly variable weather is flooding more nests. They also suspect disease and loss of genetic diversity.

The reason could also be all of the above, Noss said, with the various factors acting together in what scientists call an "extinction vortex."

The bird, a subspecies of grasshopper sparrows, eats grasshoppers and sings like one, with a "tick, tick, buzz." It also runs - hidden by dry-prairie grasses - as much or more than it flies, bedeviling researchers' attempts to learn more about it.

Sparrow advocates and researchers, including those at Audubon of Florida, Archbold Biological Station and government agencies, think it's likely that some sparrows will have to be captured and bred in captivity to prevent them from disappearing altogether.

Such a possibility is hauntingly reminiscent of an earlier, shameful chapter in the history of Florida's environment, when the dusky seaside sparrow of east Central Florida was all but annihilated by mosquito eradication in marshes surrounding Kennedy Space Center.

A frantic effort to net the last of those birds for captive breeding in the 1980s had a tragic ending; only males were found, and attempts to have them mate with a related subspecies failed.... more. ..