Only 100 Tigers Are Left in Bangladesh’s Famed Forest
More accurate counting methods for assessing tiger populations reveal that far fewer tigers live in Bangladesh’s Sundarbans region than thought.
Only about 100 tigers roam the mangrove forest, according to a new survey conducted by the Bangladesh government—hundreds fewer than recorded in 2004.
The new numbers come after a yearlong survey that wrapped up in April and used footage from camera traps placed around the 3,860-square-mile wildlife reserve to identify individual tigers, Agence France-Presse reported. That’s compared with the 2004 survey that estimated that 440 tigers were living in the region.
The new survey—yet to be publicly released—depicts a more accurate figure for the region’s royal Bengal tiger population, Bangladesh wildlife conservator Tapan Kumar Dey told AFP. “Plus or minus, we have around 106 tigers in our parts of the Sundarbans.”
The wildlife reserve contains the largest mangrove forest in the world, straddling India’s east end—where 72 tigers were reported in that country’s tiger census earlier in the year—and Bangladesh’s southwestern border, the site of the new census. The region was thought to contain the highest density of the endangered tigers in the world—something the new figures discount.
So what changed? Aside from possible increases in poaching and habitat degradation along the edges of the reserve, the previous population estimate may not have been accurate.
The 2004 survey was based primarily on wildlife tracking skills—paw prints were the main source of data gathering—while the new survey used camera traps in combination with tracking signs for a more accurate count.
“The 440 figure was a myth and an imagination,” Y.V. Jhala, professor at the Wildlife Institute of India, told AFP. “Bangladesh parts of the Sundarbans with its prey size can support up to 200 tigers.”
The news comes following India’s announcement in January that its population of endangered big cats was on the rise, increasing nearly a third from 1,706 tigers in 2011 to 2,226 tigers in 2014.
Worldwide, only an estimated 3,200 tigers are left in the wild—a majority of them living in India. That’s compared with the more than 100,000 that survived at the turn of the 19th century. Tiger numbers in India dipped to a record low of 1,411 in 2008, with many fearing the animals were on the fast track to extinction. Better management across the world’s 40 tiger reserves, renewed efforts to curb the tiger skin trade, and making way for more tiger habitat—even relocating whole villages—have stopped the downward trend.
But obtaining accurate counts across country lines is important for governments and conservationists in determining the true health of the species and figuring out where poaching and habitat degradation is having effects.
Bangladesh is one of 13 countries that has a population of tigers, and the new census is the first attempt in more than a decade to get an accurate count of the animals within its boundaries. Wild tiger populations have been counted in India, Nepal, and Russia; China, Bhutan, and Bangladesh will soon release census data as well. That leaves the tiger populations in Malaysia, Indonesia, Thailand, Myanmar, Laos, Cambodia, and Vietnam still unknown.
Without an accurate count, it will be hard for these countries to meet the goal established in 2010 of doubling the world’s tiger population by 2022.
“Many countries don't know the reality on the ground and can't take the appropriate action” to meet the goal, said Mike Baltzer, head of World Wildlife Fund’s Tigers Alive Initiative.
Even with the new camera-trap style of surveys, Arjun M. Gopalaswamy, a professor at Oxford University, said the tiger figures could still be inaccurate. He and fellow researchers worked on a paper that identified potential shortcomings in the new Indian data that showed a surge of tigers.
Such studies involve laying out a large number of camera traps along well-used tiger trails and sampling within a short period of time over a portion of an animal’s range. The data is then analyzed and statistically modeled over a wider area to give estimates of an entire population range.
“Any violation of these assumptions starts compromising the accuracy of tiger density estimates,” Gopalaswamy said. “The new report indicates that the sampling went on for about a year, which will likely produce unreliable results, and there are no details about the sampling procedure.”
Still, the new camera trap studies are an improvement on the tiger paw tracking studies, which probably contributed to the inaccurately high number given for tigers in Bangladesh in 2004.
“It is not entirely surprising that tigers survive in low densities in the Sundarbans,” Gopalaswamy said. "There was a separate study conducted about 15 years ago that used camera-trap surveys along with capture-recapture sampling, which indicated low tiger densities.”