Threatened Frogs Disappear with Forests: Oil Palms Endanger Amphibians in Malaysia

Amphibians are one of the most threatened groups of species in the world. Now, researchers have found something else that should worry us. They've discovered that oil palm plantations in Malaysia are causing threatened forest frogs to disappear as they're replaced by common species that move in on their turf.

Amphibians play a crucial role in ecosystems. They act as efficient predators of insects and also provide valuable nutrients to creatures further up the food chain. In addition, some play an important role in nutrient cycling. Despite all of these positives, though, amphibians have been declining rapidly. In fact, researchers found in another study that overall, populations of amphibians are vanishing from their habitats at a rate of about 3.7 percent each year--that means these species will disappear from half of their habitats in about 20 years.

Unfortunately, it seems that this same trend is occurring in frog populations. Planting oil palm plantations leads to the loss of natural forests and peat lands. In addition, the practice plays havoc with ecosystems and biodiversity. In order to examine how this affects native species, researchers travelled to Peninsular Malaysia and spent two years studying communities of frog species in four oil palm plantations and two areas of adjacent forest.

"The impact we observed is different from that observed previously for mammals and birds," said Aisyah Faruk, one of the researchers, in a news release. "Instead of reducing the number of species, oil palm affects amphibian communities by replacing habitat suitable for threatened species with habitat used by amphibian species that are not important for conservation. This more subtle effect is equally devastating for the conservation of biodiversity in Malaysia."

Amphibians are the most threatened vertebrates in the world, and about 40 percent of them are at risk of extinction. This particular phenomenon in Malaysia may just hurry some frog species on their way to an eventual population collapse. The peat swamp frog is just one of the declining species currently threatened due to the deforestation. Since it only inhabits shallow gentle streams, swampy areas and very flat forests, it's likely to disappear entirely if palm oil plantations continue to take over the area.

"Existing practices in managing oil palm are not accommodating the highly threatened forest frog species in Malaysia which urgently need saving," said co-author Trent Garner, one of the researchers, in a news release.

Currently, the researchers are trying to figure out a way to make oil palm planting sustainable. They're working with Malaysian palm oil producers in order to determine if simple modifications to agricultural practices may bring back some of the forest species into certain areas.

The findings are published in the journal Conservation Biology.