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Among the most endangered birds in North America is the Florida grasshopper sparrow. The tiny sparrow is found only on the prairie of Central Florida. Fewer than 150 are believed to remain. And the reasons for the birds decline are not well understood. Amy Green of member station WMFE reports on the effort to rescue the Florida grasshopper sparrow from extinction.
AMY GREEN, BYLINE: The sun rises over the Central Florida prairie sending pink rays over the saw palmetto and wiregrass. In the distance, stands of oak trees obscure the horizon.
ERIN RAGHEB: When the light is like it is right now, we call it the golden hour.
GREEN: That's why Erin Ragheb of the Florida Fish and Wildlife Conservation Commission works quickly.
RAGHEB: Because you've got this little window of time where some of the birds like fledglings or females that wouldn't normally be singing - they may come up out of the wet grass to dry their feathers and preen.
GREEN: She drives a metal stake into the earth using her foot then steps through knee-high vegetation and ankle-deep water unfurling a 39-foot net across the prairie. Not far from Walt Disney World in the headwaters of the Everglades, the prairie is home to the last wild population of the Florida grasshopper sparrow.
Ragheb aims this morning to catch a fledgling. Beside the net, a speaker concealed in a shrub chirps recorded songs of the sparrow as she hopes to lure one out.
RAGHEB: The bird has a really fine-detailed, scalloped pattern on the back of, like, rusty browns and blacks and white. It's very striking.
GREEN: She wants to better understand the sparrow's population here so she can learn why it's collapsing even in a pristine habitat. The Florida grasshopper sparrow would be the first confirmed bird extinction in the continental United States since the dusky seaside sparrow, also found in Florida, died out in 1987.
PAUL REILLO: This might be the last gasp, genetically, to save the Florida grasshopper sparrow.
GREEN: Far from the prairie within a row of cages, fledglings perch on slender branches. Paul Reillo works at the Rare Species Conservatory Foundation's Captive Breeding Center outside of West Palm Beach. He says recordings of wild Florida grasshopper sparrows help them learn to sing.
The fledglings are among 21 Florida grasshopper sparrows housed here. Reillo says they were rescued from failing or flooded nests on the prairie after years of deliberation over whether taking sparrows for captive breeding might further diminish their fast-dwindling wild population.
REILLO: Captive breeding I think is universally recognized in the conservation community as being one of the last intervention efforts that you undertake. We want to keep species in the wild. We want endangered species to recover in the wild.
GREEN: The debate was settled last year when a mother was found dead outside of a nest of chicks. Then this spring, a series of heavy rains inundated the prairie, leaving eggs floating and threatening to wipe out a generation of the critically endangered sparrow. Reillo and his staff raised the orphaned chicks and incubated the eggs, feeding the hatchlings on an exhausting schedule of every 40 minutes up to 18 hours a day.
REILLO: We started with a rather motley misfit group of founders, and yet we saw amazing reproductive effort. That's a very hopeful sign.
GREEN: The goal is to reintroduce the captive-bred Florida grasshopper sparrows into the wild, but Reillo says that's at least a few years away.
Back on the Central Florida prairie, Ragheb checks the net for fledglings, but the net is empty.
RAGHEB: Even on a good day, it's hard to know if you're going to catch any birds.
GREEN: The Florida grasshopper sparrow is considered a flagship species representative of a habitat that few Floridians have seen. As much as 90 percent of the prairie has been lost to development, and that's believed to be a primary cause for the sparrow's collapse.
RAGHEB: So I'd say especially for fledgling captures, you know, probably every dozen nets we set up, we might catch one bird. So it's a lot of work. It takes a lot of patience.
GREEN: Researchers like Ragheb also are exploring other reasons like disease. They don't want to reintroduce captive-bred Florida grasshopper sparrows back to a broken habitat.
RAGHEB: Just look at the sparrow, and look at how determined they are at being successful. And so I feel like we need to persist with the same level of determination that the sparrow does.
GREEN: Ragheb says the work can be discouraging, but she hopes that even as the Florida grasshopper sparrow teeters on the brink of extinction, lessons learned from its conservation can help bolster other bird species of concern on the vanishing Central Florida prairie. For NPR News, I'm Amy Green. Transcript provided by NPR, Copyright NPR.