NC Zoo aids effort to conserve Puerto Rican crested toads

The N.C. Zoo doesn’t usually release its animals into the wild, but it has made an exception for an amphibian from Puerto Rico.

The zoo recently shipped more than 400 Puerto Rican crested toad tadpoles to Puerto Rico to be released in the wild as part of the zoo’s increasing conservation efforts.

The crested toad – the only toad native to Puerto Rico – is a critically endangered species. The decline in its population can largely be attributed to habitat loss and degradation, said Dustin Smith, the curator of reptiles, amphibians, fish and invertebrates at the N.C. Zoo.

“The toads have always been rare,” Smith said. “They were described for the first time over 150 years ago, and even then, only a few were found. For more than half of their existence, they have been rare to the point where people thought they were extinct.”

During the past 30 years, the population of crested toads in the wild has fluctuated between 300 and 3,000. Since 1984, 19 institutions participating in a Species Survival Plan program have sent more than 350,000 tadpoles to Puerto Rico.

Smith said the N.C. Zoo currently has about 30 toads, which are bred so that tadpoles can be sent to Puerto Rico. He explained that the toads are “kept in a quarantine room” where zoo staff wear gloves and boots so that the toads don’t catch any local diseases, and don’t transfer any diseases to the local animals.

The project, Smith said, appears to be “moving in the right direction.” He said scientists have recently visited breeding sites on the north side of the island to listen for calling toads and look for breeding activity. The results suggest the efforts of zoos in the U.S. are paying off, because the toads had completely disappeared from that side of the island in the 1990s.

But he cautioned against declaring the project a success too early.

“We can’t say it’s a definite success yet because we have to see how long this can be sustained,” Smith said. “That’s the question with all projects like these – whether or not they’re sustainable in the wild.”

Richard Bergl, the curator of conservation and research, said conservation projects like those protecting the Puerto Rican crested toad are a “central part of the mission of the zoo.”

“As our work expands and as we embark on a refresh of a lot what’s going on in the public areas of the zoo, we’re going to be putting the conservation work we do out front,” Bergl said.

The Puerto Rican toads aren’t the first animals the zoo has set loose into the wild; the zoo also has been involved with a release of red wolves, Bergl said. But more common are conservation projects that don’t involve breeding animals, such as using satellite tracking devices to better understand the flight patterns of vultures in East Africa to determine when they might be exposed to poisons. In Southern Africa, Bergl said, the zoo has helped develop a “high-tech anti-poaching database” to help protect at-risk species of carnivores, such as lions and cheetahs.

He explained that the zoo’s conservation work is focused primarily in North America and Africa because those are the countries where animals at the zoo come from.

Visitors to the zoo often don’t realize the extent of the work the zoo does outside of animal exhibits, Bergl said. He added that when visitors make donations, that money often goes directly to the zoo’s conservation programs, which are funded through the North Carolina Zoo Society, donations and purchases at the gift shop.

“Often people in the U.S. might hear about elephant poaching or rhino poaching and think there isn’t a lot they can do,” he said. “But by coming to the zoo and supporting the zoo – even just by buying things at the gift shop – you are directly supporting that work. You’re taking steps to actually conserve these endangered species.”

This story was originally published October 31, 2016 at 6:04 PM with the headline "NC Zoo aids effort to conserve Puerto Rican crested toads."