The croaking of the Houston toad is virtually never heard in its namesake: none of the toads live in the wild in Houston. And efforts to help them live in other areas have run up against drought, wild fires and bulldozers. But there’s a new effort to help the little toad survive.

If you know exactly where to listen, you can hear the shrill call of the Houston toad, living many miles west of Houston in one of the few places where you can still find them. There may be only hundreds remaining and that's why the toad is a federally designated Endangered Species.

To see a Houston toad up close, we were allowed inside the Houston Zoo's special breeding facility. Here in rows after aquariums, they've been breeding the toad and have harvested over a million eggs since 2013. The zoo is the only place in the world doing this work on this scale. The eggs are eventually released into ponds in protected habitats.

Toad keeper Melissa Spradley is holding a male that here indoors doesn't give that shrill call but instead gives us a little chirp: "He's making a quiet little croak." (Click above on "Listen to the Radio Story” to hear it).

"This animal is uniquely Texas," says Stan Mays who joined us in the breeding facility. He's the Zoo's curator for amphibians.

"It was well adapted to the Houston area before there was urbanization. It's a Texas native and you hate wiping out anything that's a Texas native," Mays says.

But stopping the Houston toad from being wiped out hasn't been easy. Unlike the Gulf Coast toad that you see all the time, the Houston toad is much more sensitive. It could not adapt to the Houston region's transformation from prairies and forests to parking lots and subdivisions.

Now, one of the only remaining habitats for it is in and around Bastrop State Park, 35 miles east of Austin. But the drought and then the wildfires in 2011 decimated that habitat, driving the Houston toad north and east of the park. So critical is this area to the toad's survival that the Federal government designated 124,000 acres for protection under the Endangered Species Act. The point is to limit land use so the toad can thrive. At least, that's the idea.

"They bulldozed several hundred acres," says biologist Mike Forstner, at Texas State Univeristy. He is considered by many to be "the" Houston toad expert. He’s talking about what happened earlier this year outside Bastrop.

Forstner says some of the supposedly protected habitat where they had previously heard "choruses" of the toads’ call was destroyed.

"In the spring of 2016, extensive clearing, bulldozing, chain-sawing, and tree removal occurred within the chorusing habitat and in 2016 we did not detect those large choruses," Forstner says.

According to Colton Stabeno at Bastrop County's Lost Pines Habitat Conservation office which manages the habitat and issues land use permits, a farming operation cut down 400 acres of trees. Stabeno says his office reported the de-forestation to the federal wildlife service. But the service couldn't tell us anything more. However, state wildlife officials had plenty to say about working with landowners.

"What we have going right now that's up for public review and comment is a programmatic safe harbor agreement,"says Meredith Longoria with Texas Parks and Wildlife.

She’s helping develop a "Safe Harbor" program. It would be a legal agreement to allow landowners to do things to help toads thrive but still be able to maintain, say, ranching and not be held liable if some of the toads are inadvertently killed by, say cattle. Longoria says the hope is "…to really boost, ramp up that effort of partnering with landowners to improve habitat for the toad."

Will it work? No one knows but back at the Houston Zoo, Stan Mays says, it's worth the effort: "The last Houston toad was found about 1975 in Houston just south of Hobby Airport. It's only found in Texas, no place else in the world. For that reason alone we feel an obligation to help preserve it."