New Research Suggests Tigers Can Come Back From Brink of Extinction If Habitats Are Preserved
Apr 1, 2016
Satellite analysis reveals tiger habitats are more intact than expected: an area large enough to double the wild tiger population remains
RESOLVE researchers published findings today in the journal Science Advances on the status of habitat for tigers. Some key takeaways from the study:
- Tigers need large areas to survive but if well protected, populations can rebound quickly – Nepal and India experienced 61 and 31 percent increases, respectively, in their tiger populations recently thanks to better habitat protection and anti-poaching efforts.
- The global tiger population now stands at fewer than 3,500; the international commitment is to double the population by 2022.
- Scientists found less than 8 percent (79,600 km2) of global tiger habitat was lost between 2001 and 2014, habitat that could have supported about 400 tigers.
- 98 percent of forest loss in tiger habitat occurred in just 10 landscapes, primarily in Indonesia and Malaysia, where oil palm plantations are driving deforestation.
- This is the first major study to use high and medium-resolution satellite data from Global Forest Watch to examine the impact of forest loss on tiger populations.
Enough forested habitat remains to bring the tiger back from the brink of extinction, according to new analysis published in Science Advances today by researchers at the University of Minnesota, RESOLVE, Smithsonian Conservation Biology Institute, Rainforest Alliance, Stanford University and World Resources Institute (WRI). The study found forest loss was lower than expected in tiger habitats, suggesting there is more than enough habitat remaining to achieve the international commitment of doubling the wild tiger population by 2022 (an initiative known as “Tx2”) with additional conservation investment.
Tiger populations can rebound quickly when habitat and prey are abundant and hunting is controlled. For example, Nepal and India have reported 61 and 31 percent increases in their tiger populations, respectively. This is partly thanks to conservation initiatives like the preservation of the cross-boundary Terai Arc Landscape. Reaching the Tx2 goal will require that any significant future tiger habitat loss is prevented, key corridors are restored between remaining forest fragments, nations implement green infrastructure to prevent habitat fragmentation, and conservation managers translocate and reintroduce tiger populations where necessary.
The study, “Tracking changes and preventing loss in critical tiger habitat,” shows that less than 8 percent (nearly 79,000 km2 or 30,000 mi2) of global forested habitat was lost from 2001-2014. This rate of forest loss is lower than anticipated, given that tiger habitats are generally distributed in fast-growing rural economies, some with high population densities and facing severe pressures from industrial agriculture.
Despite lower-than-expected levels of forest loss within tiger habitat, the study also confirms the precariousness of the species’ survival. The researchers estimate that forest clearing since 2001 resulted in the loss of habitat that could have supported an estimated 400 tigers. This is potentially devastating, considering the current global tiger population is fewer than 3,500 individuals. Furthermore, the study did not consider the deleterious effects of poaching and prey loss within these landscapes.
“After decades of working in tiger conservation, it is great to have some encouraging news for once,” said Eric Dinerstein, Director of the Biodiversity and Wildlife Solutions Program at RESOLVE and a Senior Fellow at WRI. “But illegal hunting of both tigers and prey can result in ‘empty forests’ without enough food or shelter to support large predators like tigers. Measuring and combatting this sort of forest impoverishment and its effects will be essential. It complements our efforts to identify habitat poaching in this study.”
The vast majority (98 percent) of tiger forest habitat loss occurred within just 10 landscapes, often driven by the conversion of natural forest to plantations for agricultural commodities such as palm oil. The landscapes with the highest percentage of forest clearing were in areas of Malaysia and Indonesia with heavy oil palm development, such as the Bukit Tigapuluh ecosystem in Sumatra, which has lost more than two-thirds (67 percent) of its forest since 2001, resulted in a loss of habitat sufficient to support an estimated 51 tigers. Palm oil development remains an ongoing threat— in Indonesia alone, more than 4,000 km2 (1,544 mi2) of forest habitat, an area five times the size of New York City, have been allocated for oil palm concessions.
GFW also provides monthly and in some cases weekly tree cover loss alerts that can empower park rangers and communities to monitor and protect tiger habitat, even at the finest scale of a single forest corridor used by a dispersing male tiger.
“It is remarkable and unexpected that tiger habitat has been relatively well-preserved over this 14-year period,” said the study’s lead author, Anup Joshi from the University of Minnesota. “It is not a sign that we are in the clear yet, but it does show us that tigers can potentially recover from the edge of extinction if we make the right forest management choices. We are seeing this already in areas like the border between Nepal and India, where forest cover is recovering with the help of communities and tigers are coming back in a big way.”