A Rare Chance to Save an Entire Nation’s Frogs From Extinction
The fungus (officially known as Batrachochytrium dendrobatidis, or Bd) has driven at least 100 frog species—and perhaps as many as 200—into extinction and caused catastrophic population declines in many others since it first appeared in the 1970s. It has traveled around the world over the past few decades, usually through the pet trade, and devastated frogs and other amphibians wherever it appears.
Madagascar has apparently been spared so far, but it’s easy to see why scientists and conservationists are worried. The island off the southeast coast of Africa holds more than 300 amphibian species—7 percent of the world’s total number of amphibians. Ninety-nine percent of those species live nowhere else on Earth.
Despite scientists’ warnings of a potential mass die-off in Madagascar, however, hope is not yet lost for the country’s unique frogs. A paper published this week in PLOS One finds that the chytrid fungus is not widespread on the island, and the frogs there do not show signs of disease.
“Although chytrid has been detected in the country, my analysis strongly contradicts the doom-and-gloom sentiment conveyed by other researchers,” said the paper’s lead author, Jonathan Kolby, a National Geographic Young Explorer and a doctoral candidate at James Cook University in Queensland, Australia.
Kolby’s research found that the chytrid fungus is not a permanent resident on the island in that it is not yet strong enough there to have self-sustaining populations. He said that means there’s enough time to take preventive action to help ensure that Madagascar’s frogs remain safe.
He describes “simple biosecurity measures” that could stop the flow of Bd into the country. The steps he suggests include inspecting cargo entering the country to prevent the appearance of invasive, disease-carrying amphibians, creating surveillance programs for those potential invaders, and using bleach on—or burning—any export cargo containers on which Bd has been detected.
He also recommends teaching conservation staff to wear gloves whenever they handle amphibians, changing them for each animal, and to bleach their boots and other equipment whenever they travel to new field sites to prevent the likelihood of moving disease from one area to another.
Kolby is critical of the direction chytrid prevention has taken in Madagascar, saying it focuses too much on “preparing for disease outbreak rather than prevention.” He said efforts such as searching for anti-Bd probiotic treatments and building sites in which to store captive populations are important, but they miss the opportunity to block the fungus in the first place.
“The amphibian conservation community has never before had a clear opportunity to interrupt and prevent Bd establishment,” Kolby said. His new research shows there may be time in Madagascar to make that happen.