African-toads - how captive breeding programmes can save a species

Submitted by shelley.fischer on Sun, 05/09/2010 - 16:53

The Kihansi spray toad Nectophrynoides asperginis was declared extinct in the wild last year. Thanks to a breeding programme in two US zoos a population of the toads has been returned to Africa.

The Extinction, as reported by November 2009: The Kihansi spray toad Nectophrynoides asperginis, which still survives in a number of zoos in the United States, had lived on just two hectares along the Kihansi gorge in Tanzania. The toad was specially adapted to the spray region of the Kihansi waterfall, which kept its small environment at a constant temperature and humidity.

The construction of a dam, funded by the World Bank, upset the flow of the waterfall and devastated the species. The toad was only discovered a year into construction of the dam, along with two plants, which were endemic to the microenvironment like the toad.

In 2009 the IUCN Red List updated its assessment of the Kihansi spray toad, moving the species from Critically Endangered to Extinct in the Wild. With that another amphibian species has been lost to a combination of habitat loss and the devastating amphibian disease, the chytrid fungus.

Update - The 20th August 2010

One hundred extremely rare Kihansi spray toads, a species last seen in Tanzania in 2004 after their habitat was destroyed by a new hydroelectric dam, have been flown home from the Bronx and Toledo zoos in the US.

They were taken to a "state-of the-art propagation centre" in Dar es Salaam where staff, presumably detecting a lot of tiny smiles, described the toads as "cheerful".

Well they might be. If all goes well they will soon be returned to their parents' old hopping grounds, cooled by an artificial sprinkler system to mimic their original misty home.

Unusually among toads, the females do not lay eggs that hatch into tadpoles, instead giving birth to fully formed young.