Call for action on lethal frog fungus

A Christchurch biologist would like to see the sale of tadpoles and frogs banned after the spread of a killer frog fungus in Canterbury.

Dr Bruce Waldman discovered the lethal chytrid fungus among southern bell frogs in a Godley Head pool last November. It has now spread to other parts of Christchurch, West Melton and Springston.

The pet trade frequently collects tadpoles and frogs from the Godley Head pool. In one case teenagers had sold tadpoles from Godley Head to the owners of a pool in West Melton. While tadpoles are not affected by the disease until they metamorphose, they are carriers and the tadpoles may have infected adult frogs living in the pool. Dr Waldman said he would like to hear from people who observed frogs which appeared lethargic and had trouble righting themselves. Less obvious was the colouration on their bellies and skin scarring. Frogs with the disease lived longer when they were out of the water.

“I don’t want to scare people,” said Dr Waldman. “Frogs are wonderful creatures.” However, until scientists had a clear idea of the extent of the problem he would like to see a ban on the sale of tadpoles and frogs from pet shops and also restrictions on the transport of frogs between the North and South Islands.

The fungus, which does not affect humans, has killed more than 90 per cent of infected frogs in Australia and is thought to have contributed to the extinction of six frog species there. It damages the frogs’ skin and kills them by either releasing toxins or by suffocating the frogs as they breathe through their skin.

No cure has yet been found for the disease which had not been identified in New Zealand until last November. Those who observe sick frogs should contact Dr Waldman at bw@zool.canterbury.ac.nz or ph (03) 364 2066.