Tiger populations in a national park in India are stable despite relentless poaching because the wild cats breed like rabbits.
A nine-year study conducted in India's Nagarhole National Park found that an average of 23 percent of the park's tigers either moved away or died each year from natural causes or from poaching by hunters who kill the animals for their body parts. Yet, despite the loss, the park's tiger population remained stable because the wild cats are fast breeders, with females giving birth to three to four cubs per litter every three to four years.
"This study shows that even well-protected wild tiger populations have naturally high rates of annual loss, and yet do fine because of their high reproductive rates," said lead research Ullas Karanth of the Wildlife Conservation Society (WCS).
The study, conducted by researchers from WCS and the U.S. Geological Survey (USGS), is detailed in the journal Ecology.
In other parts of the world, however, high breeding rates can't replenish tiger populations fast enough to counteract the negative effects of poaching. Another WCS study, detailed in a recent issue of the journal Animal Conservation, found that tiger numbers in a protected area along the Laos-Vietnam boarder are extremely low due to commercial killing of not only the big cats but also of their prey. By wiping out animals the tigers feed upon, hunters are inadvertently starving the very beasts they wish to profit from.
Humans are also threatening tiger survival by destroying the cats' natural habitats. Studies indicate that tigers now reside in only 7 percent of their historic range — 40 percent less than a decade ago.
"The good news is that given the chance, tigers can replenish their numbers; the bad news is that they are not being given the chance in many parts of their range," said Alan Rabinowitz, a WCS big-cat expert.
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