- On 10 April 2016, WWF and the Global Tiger Forum announced that the world’s tiger population had finally increased “after several decades of constant decline”.
- But tiger experts Ullas Karanth and Dale Miquelle of Wildlife Conservation Society, John Goodrich of Panthera, and Arjun Gopalaswamy of the University of Oxford have called WWF’s report, and its implications, “scientifically unconvincing”.
- Governments at the 3rd Asia Ministerial Conference on Tiger Conservation also agreed to double tiger populations by 2022, which the experts say is totally unrealistic.
On 10 April 2016, WWF and the Global Tiger Forum announced that the world’s tiger population had finally increased “after several decades of constant decline”.
From “as few as 3,200” tigers in 2010, tiger numbers have risen to 3,890 tigers now, they said in a statement. For a species struggling to survive, these figures look promising.
But tiger numbers may not have “truly” increased, four tiger experts warn. The experts — Ullas Karanth and Dale Miquelle of Wildlife Conservation Society, John Goodrich of Panthera, and Arjun Gopalaswamy of the University of Oxford — have called WWF’s report, and its implications, “scientifically unconvincing”.
Tigers are elusive, and counting them is hard. Over the years, scientists have developed better monitoring methodologies that allow conservationists to miss fewer tigers in the field, and estimate tiger numbers more accurately.
An increase in tiger numbers could indicate that tiger conservation measures are working. But it could also mean that better tiger monitoring techniques have allowed more individual tigers to be counted.
“The latest report of an increase in the world’s global tiger population is based on the compilation of greater and better data due to these improved monitoring efforts, rather than valid, scientific evidence of tiger population increases,” Goodrich said in a statement.
The increase in tiger numbers could also be a result of using flawed survey techniques that may over-estimate and inflate tiger numbers. One problem, according to the experts, is that tiger numbers reported by the various tiger range countries tend to be largely unreliable.
Survey methodologies used to estimate tiger numbers are not uniform across all tiger range countries. While some countries employ rigorous camera trap or DNA surveys to estimate size of tiger populations, others use unreliable and unscientific methods such as counting tiger pugmarks or droppings. Sometimes, methodologies vary in different parts of the same country, resulting in widely varying estimates of tiger numbers.
“Using flawed survey methodologies can lead to incorrect conclusions, an illusion of success, and slackening of conservation efforts, when in reality grave concern is called for,” Karanth, Miquelle, Goodrich and Gopalaswamy write in their statement.
What the actual global tiger numbers are is difficult to say. But threats to tigers have not abated, the experts write.
Currently, tigers occupy less than six percent of their historic range, according to the IUCN. Moreover, some countries seem to be rapidly losing their viable tiger populations. For example, on April 6, conservationists concluded that the Indochinese tiger in Cambodia was “functionally extinct.” The last time a tiger was seen in the country was in 2007. Similarly, China, Vietnam and Lao PDR may have lost all viable tiger populations, the experts write.
Tigers have also lost around 40 percent of their habitat in the last decade. Poaching of tigers too has increased in recent years, they add. So “this is not a time for conservationists to take their eyes off the ball and pat each other on the back,” the experts write.
All is not gloom though. Some countries, such as India and Russia, have taken large strides towards improving tiger conservation and have seen some success.
But does this mean that tiger populations can be doubled by 2022 as governments at the 3rd Asia Ministerial Conference on Tiger Conservation believe? It is unlikely, according to the four experts.
A 2010 study found that more than 70 percent of the world’s tigers survive at 42 “source sites” or sites where “tigers occur at high densities, and which are likely to produce ‘surplus’ animals that can disperse and expand populations.” The remaining tigers occur in “sink” sites, or in habitats that are suboptimal for the tigers.
While source sites have the potential to repopulate other sites, tiger populations are growing slowly at these sites, experts say. And the slow growth is only in those source sites that are protected well. Since doubling of tiger numbers over the next decade at source sites looks improbable, tigers would have to rapidly multiply in the sink habitats. This is highly unlikely, the experts say.
“I do not believe the goal of doubling tiger numbers by 2022 is realistic,” Karanth told the FirstPost.
Goodrich added, “Tigers continue to be persecuted across their range – threatened by poaching for the illegal wildlife trade, deforestation and conflict with people when tiger prey is overhunted. Better law enforcement and rigorous scientific monitoring of tigers, their prey, and even of human effort, are all needed in order to protect wild tigers.”
Updates 04/21/2016 11:40 Eastern:
In relation to the statement by Karanth, Miquelle, Goodrich and Gopalaswamy, WWF has released a response statement.
“WWF and the GTF compiled the updated tiger population figure from the IUCN Red Data listing completed in 2015 (Goodrich et al, 2015),” the statement notes. “The IUCN assessors (including three of the authors of the statement) totalled the global number at 3159. Since then, India, Russia, Bangladesh and Bhutan published the results of their national tiger surveys. WWF and GTF updated the IUCN 2015 data with data from these surveys. Where a range was stated by the IUCN assessment, the lower end of the range was used for the updated tiger population figure. This brought the total to 3890. No additional survey work or analysis was undertaken by WWF or the GTF.”
The complete statement can be read here.