Protecting forest corridors can preserve tigers, leopards
Two independent genetic studies led by a team of Indian scientists at the Smithsonian Conservation Biology Institute (SCBI) have pointed out the need for protecting the natural forest corridors in India to ensuring a future for tigers and leopards.
The Indian subcontinent contains the largest number of tiger conservation areas, which are home to 60 percent of the world's wild tigers. Leopard range has historically extended through most of sub-Saharan Africa, along parts of the North African coast, through central, south and southeast Asia and north to the Amur River valley in Russia.
The SCBI, world's largest museum and research complex, includes 18 museums and galleries, as well as the National Zoo in Washington.
The results of the study that focused on tigers were published recently in Ecology and Evolution, and the other that tracked leopards in Diversity and Distributions. The corridors are successfully connecting populations of tigers and leopards to ensure genetic diversity and gene flow..
'This research provides crucial information about the need to maintain these vital veins to support tiger and leopard populations. These habitats and corridors in India are threatened by infrastructural developments and need to be conserved if we want to save these species for future generations,' says Sandeep Sharma, SCBI visiting scholar and lead author of the Ecology and Evolution paper.
Habitat fragmentation can divide populations of species into isolated groups, which can lead to inbreeding and a genetic bottleneck that affects the long-term viability of the population. Scientists can determine the scope of such isolation by analysing the extent to which groups of the same species from one range have become genetically distinct, the studies say.
The researchers used fecal samples to analyze the genetics of tiger and leopard populations in four reserves in central India: Satpura, Melghat, Pench and Kanha. These reserves are connected via forest corridors that tigers, leopards, humans and cattle share.
The researchers found that both tiger and leopard populations in the reserves had maintained a high level of genetic diversity. Neither tigers nor leopards were genetically distinct, with one exception among the leopards, which the scientists hope to explain with additional research.
The corridors appear to allow individuals to move between reserves, facilitating genetic exchange. However, the proliferation of roads, rail lines, mining, urbanisation and other forms of development through the corridors jeopardise these species' ability to move between reserves.
Several coal mines have been proposed in the forest corridor between the Satpura and Pench tiger reserves, as has the widening of a national highway (NH-7) and a broad-gauge railway line that cut across the corridor between the Kanha and Pench tiger reserves.
'By looking at two species, we were really able to illustrate the functionality of these corridors. Conserving a whole landscape, rather than piecemeal protected areas, would ensure a better chance for the long-term persistence of these and other species," says 'Trishna Dutta, lead author of the other paper.
Other authors of the papers include Jesus Maldonado, a research geneticist at SCBI's Center for Conservation and Evolutionary Genetics, and John Seidensticker, head of SCBI's Conservation Ecology Center, Thomas Wood in the Department of Environmental Science and Policy at George Mason University and HS Panwar, former director of Project Tiger India and Wildlife Institute of India.
The SCBI plays a key role in global efforts to understand and conserve species and train future generations of conservationists.