Some of Asia's largest animals, including tigers and elephants, are defying 12,000 years of extinction trends by coexisting with humans, according to a study led by the University of Queensland.
|Sumatra tiger on the forest's edge. Credit: UQ/Matthew Luskin|
Researchers combed through paleontological records to compare the historic distribution of Asia's 14 largest species to their current populations in tropical forests.
According to UQ's School of Biological Sciences and the Ecological Cascades Lab's Ph.D. candidate Zachary Amir, four species—tigers, Asian elephants, wild boars, and clouded leopards—have increased populations in areas with human infrastructure.
"These findings demonstrate that, under the right conditions, some large animals can coexist with humans and avoid extinction," Mr. Amir said.
"These findings call into question the widely held belief in some conservation circles that humans and megafauna are incompatible."
"There is a global trend toward 'trophic downgrading,' which refers to the disproportionate loss of the world's largest animals."
"Trophic downgrading is typically worse near humans because hunters prey on larger species." However, tigers, elephants, wild boars, and clouded leopards have larger Asian populations near humans.
"This could be the result of more aggressive anti-poaching efforts in national parks closer to human settlements and more frequently visited by tourists."
The study also discovered that deforestation was still having an impact on species, with clouded leopard numbers in particular experiencing a significant decline in those areas.
However, Mr. Amir stated that the research demonstrated that if large animal species were not hunted, they could live in relatively small habitats and close to humans.
"Previously, there have only been a few examples of large Asian species thriving in small habitats near humans," Mr. Amir explained, referring to a previous UQ study.
|An elephant in Borneo. Credit: UQ/Zachary Amir|
"Fortunately, we discovered that a broader range of animals can coexist with humans."
Two large animal species are thriving again at one of their study sites in Singapore, where poaching has been eradicated and significant forest restoration efforts have been undertaken.
Mr. Amir stated, "Singapore has actually experienced the natural re-wilding of sambar deer and wild boars, which are now frequently observed in an urban forest, the Bukit Timah Nature Reserve."
"We may see positive effects all over the world if we replicate those protection efforts in larger forests and other countries."
"However, before this can happen, humans must get their act together and limit poaching."
While there are some encouraging findings, UQ's Dr. Matthew Luskin reports that the study also found significant declines in tapirs, Sumatran rhinoceros, sun bears, guars, and other large animals.
"The key innovation of this work was to conduct a systematic investigation of the population trends of many different wildlife species across the region," Dr. Luskin said.
"We then examined whether all species showed consistent trends and whether similar parks retained similar species." Surprisingly, we discovered that no two forests now have the same group of wildlife that existed thousands of years ago."
Dr. Luskin stated that the study, which was published in Science Advances, provided an opportunity to shape the future of nature.
"These findings give hope to wildlife in forests that were previously thought to be too degraded or too close to cities," he said. "We're now looking into new conservation strategies for these unexpected locations."
Journal information: Science Advances