A MARTINEZ, HOST:
A small bird called the Florida grasshopper sparrow was on the brink of extinction just three years ago. Now it's coming back thanks to an emergency effort to breed the birds in captivity and release them on the central Florida prairie. That's the only place on Earth that they're found in the wild. WMFE environmental reporter Amy Green reports.
AMY GREEN, BYLINE: The Florida grasshopper sparrow is a drab, brown-colored bird no larger than the palm of your hand.
(SOUNDBITE OF BIRDS CHIRPING)
GREEN: That captive-raised sparrow was 45 days old when he was released last year among the saw palmetto and wiregrass of the central Florida prairie, not far from Walt Disney World. After surviving the winter, he established a breeding territory and paired with a wild mate. He was recorded this spring by a conservation group documenting the releases.
JUAN OTEYZA: They sound a bit like an insect. They go like, (mimicking sparrow).
GREEN: Juan Oteyza of the Florida Fish and Wildlife Conservation Commission has spent hours on the prairie observing the sparrows. Wildlife agencies began releasing the sparrows on the prairie in 2019 after agonizing debate. No one knew whether the effort would be successful. The sparrow was North America's most endangered bird, with only about 80 left in the wild. Some feared the releases would condemn the sparrows to extinction - for example, if a disease spread from captive birds to wild ones. Since then, the sparrows have wowed researchers with their resilience. The captive-raised sparrows have paired and bred with their wild colleagues, producing offspring that also are breeding. Oteyza says the number of birds at the initial release site has doubled. And the wild population has jumped to more than 120.
OTEYZA: We often just see them and don't really think of them as released birds. And that's a great thing, right? They just incorporated into the wild population really well.
GREEN: Some of the captive-raised sparrows began their lives far from the prairie at the Brevard Zoo.
(SOUNDBITE OF DOOR SLAMMING)
GREEN: The zoo's Kelly Currier keeps her voice low to avoid spooking the skittish sparrows, as her colleague steps inside a wooden and wire-mesh enclosure with a morning meal of crickets and worms.
KELLY CURRIER: It is how you act when you're in here. If you are calm, they can feel it. And if you are slow, it affects how they are going to act as well.
GREEN: It's just like a baby.
CURRIER: Exactly. Yeah.
GREEN: The Brevard Zoo is one of four locations where the sparrows are being raised. Here, each enclosure is like a little patch of the prairie, with tall, wild grasses and branches where the sparrows can perch and look out. The staff spends hours preparing their meals and observing them. Currier has a favorite sparrow she nicknamed Wild One for the bird's fierce devotion to her hatchlings. Still, Currier says, she is never sad to see them go to the prairie.
CURRIER: I want for every one of these birds to be out there living their life that they want to live. So I'm so happy when they go. It's like, bye. Good luck.
GREEN: The Florida grasshopper sparrow still faces many threats. The population remains so small that one thing could wipe it out, like a disease or weather event. And Oteyza says the sparrows' plight is a sign of other problems.
OTEYZA: This problem may be associated with climate change. It may be associated with habitat degradation or habitat loss.
GREEN: Perhaps the biggest threat here in fast-growing central Florida is the prairie itself is vanishing as it is overtaken with development.
For NPR News, I'm Amy Green in Melbourne, Fla.
(SOUNDBITE OF ANOMALIE'S "DRIBBLE") Transcript provided by NPR, Copyright NPR.