Nashville Zoo recently sent its fifth group of Puerto Rican crested toad tadpoles to Puerto Rico for reintroduction at different parts of the island, as part of the Puerto Rican Crested Toad Species Survival Plan (SSP). These tadpoles are helping to bolster the population size of the federally endangered Puerto Rican crested toad in its native habitat.
The 958 tadpoles produced at Nashville Zoo will be released in Puerto Rico at the same time as tadpoles produced at other zoos and aquariums in collaboration with the U.S. Fish and Wildlife Service (USFWS). This method provides greater genetic diversity, increasing the overall health of the population.
The most recent tadpoles born on June 17 were the first tadpoles Nashville Zoo Puerto Rican crested toads had produced since 2015. Breeding protocols for Puerto Rican crested toads are extremely precise. One breeding event occurs at the Zoo each year, which involved cooling the recommended toads who live in a bio-secure room, from 81°F to 66°F. The toads are then transitioned back to a warmer temperature and placed in a rain chamber that stimulates breeding.
In recent years, breeding has been unsuccessful because the Zoo’s toads were too young to breed and or the eggs were infertile.
For a decade, Nashville Zoo has been involved with Puerto Rican crested toad conservation. The Zoo first acquired the species in 2008 and had its first successful breeding in 2012. From 2013 to 2015, the Zoo sent 10,365 tadpoles to Puerto Rico for release.
Puerto Rican crested toads were the first amphibian placed on an SSP. The species experienced drastic population declines due to habitat loss and the introduction of invasive species. At one point, this critically endangered species was thought to be extinct, but a small wild population has remained in Guanica National Forest. Nashville Zoo, the USFWS, Puerto Rican Wildlife Agencies, other zoos and aquariums and local institutions have all contributed to improving the status of Puerto Rican crested toads in the wild.
As the only toad native to Puerto Rico, Puerto Rican crested toads play an important role in their environment. Nashville Zoo plans to continue breeding Puerto Rican crested toads and participating in their SSP.