Being immersed in CI’s “Search for the Lost Frogs” campaign, I was excited to read another piece of amphibian news this week from the Wildlife Conservation Society: 100 captive-bred Kihansi spray toads (Nectophrynoides asperginis) could help bring the species back from the brink of extinction in its native African habitat.
The toads, which were bred at the Bronx Zoo and the Toledo Zoo, were recently flown to Dar es Salaam, Tanzania’s commercial capital, where they will be held at a propagation center before reintroduction into the wild.
The Kihansi spray toad’s range is a classic example of the micro-habitats that many amphibian species have evolved to inhabit. The species was discovered in 1996, living exclusively in the spray of the waterfalls of Kihansi Gorge in eastern Tanzania – an area smaller than 2 hectares (5 acres). After the construction of a hydroelectric dam in the gorge, decreased water flow dramatically reduced its habitat. IUCN declared the species Extinct in the Wild in 2009… but not before several hundred individuals were collected for captive breeding.
As a former zookeeper who has spent countless hours cleaning monkey exhibits, chopping frozen fish and de-worming poison dart frogs, I can personally attest that zoo employees are among the world’s most dedicated animal lovers and conservationists. The Kihansi spray toad project is just one example of the huge role that zoos can play in breeding and reintroducing threatened species into the wild. There are many uncertainties with a project like this; 100 individuals is, after all, an incredibly small population that could easily be wiped out by a variety of factors. Fortunately, in addition to the toads waiting to be released into the wild in Tanzania, thousands more remain in captivity at the Bronx and Toledo Zoos – providing a lifeline for the species in case the first reintroduction attempts are unsuccessful.
The government officials and field conservationists in Tanzania are also working hard to preserve this high-profile species. In order to re-create the toad’s habitat in the Kihansi Gorge, the Tanzanian government has set up a sprinkler system that mimics the waterfall spray on which the amphibians depend.
Although the Kihansi spray toad’s decline in the wild may be the result of human action, its survival now depends on it.