Two years ago, after an intense 13-year quest, scientists concluded that the Formosan clouded leopard (Neofelis nebulosa brachyura) had gone extinct in Taiwan. But a new paper by the same scientists contains an interesting revelation: The island nation's ecology has improved so much since the leopards disappeared that they might once again thrive there.
Clouded leopards disappeared from Taiwan decades ago, probably in the 1980s after intense overhunting for their furs followed by destruction of their forest habitat and declining populations of the cats' prey species. Here's the thing, though: According to the new paper, published November 20 in Oryx, Taiwan has done such a good job slowing deforestation and protecting its other wildlife over the past few decades that the island could once again support populations of leopards.
As Po-Jen Chiang of the Institute of Wildlife Conservation in Taiwan and his fellow authors point out, Taiwan banned commercial hunting in 1973 and stopped logging its natural forests in 1991. Although poaching and habitat loss continue, populations of some mammalian species, such as the Formosan macaque (Macaca cyclopis) and Reeves's muntjac (Muntiacus reevesi), have grown—enough to make them pests on farmlands. The authors suggest that lack of predation by the now-missing clouded leopards could have something to do with this overpopulation of some mammalian species.
Meanwhile, Taiwan's natural forests have had time to regenerate. The researchers concluded that the island now has enough broadleaf, conifer and cypress forests, along with natural vegetation to support the prey mammals. Not only that, but prey populations appear to be large enough to support clouded leopards. Populations of the five species most likely to serve as prey for the big cats have all declined over the past 50 years due to human encroachment on their habitats, but their numbers are still healthy enough to withstand predation.
All told, the researchers calculated that 24 percent of Taiwan—more than 8,500 square kilometers—contained suitable habitat for between 500 and 600 clouded leopards.
Where would those leopards come from? The authors suggest that the cats of mainland Asia would make strong candidates for reintroduction. Genetic studies published in 2006 and 2011 indicate that the cats on Taiwan probably weren't a unique subspecies after all, so mainland clouded leopards would not exactly be aliens to the island.
The main clouded leopard species (N. nebulosa) is currently considered vulnerable to extinction, with a total population of fewer than 10,000 individuals and no populations larger than 1,000 animals. Their habitats are "undergoing the world's fastest regional deforestation rates" according to the IUCN Red List and trade in their skins and bones continues to devastate their populations. As the authors wrote, Taiwan could become a much-needed refuge for clouded leopards in the future. That is not only something the species sorely needs, it could benefit the island's ecology as well.
Photo: An 1862 painting of a Formosan clouded leopard by Joseph Wolf, public domain
