The researchers found that the 20 most promising tiger landscape preserves could support 10,500 tigers, including 3,400 breeding females. They also pointed to historical examples of success. During civil conflict in Nepal, tiger numbers plummeted, but the cats did not disappear. Tigers from India were able to follow networks of wilderness to re-populate the area.
In the 1940′s tigers were nearly wiped out in eastern Russia, but tigers from northeast China repopulated the area. Russia's tigers are currently returning the favor and moving back into China's Changbaishan mountains after tiger populations there hit new lows in the 1990′s. A recently developed series of habitat corridors makes this migration possible.
A connected network of parks in India keeps a healthy population of 300 tigers in Nagarahole National Park and other connected preserves.
On the other hand, tigers were wiped out by poachers in Sariska and Panna tiger reserves in 2005 and 2009, but could not return on their own because the parks were isolated.
Tigers currently range across 13 Asian countries. The feline predators once numbered about 100,000 in the early 1900′s but current estimates are as low as 3,200. Tigers have died out due to poaching, habitat loss, and loss of prey to human hunters.
"We absolutely need to stop the bleeding, the poaching of tigers and their prey in core breeding areas, but we need to go much further and secure larger tiger landscapes before it is too late," said World Wildlife Fund chief scientist Dr. Eric Dinerstein, a co-author of the study.