With help, tigers clawing back in Southeast Asia

Moreover, the scientists feel even better days lay ahead for this population of the iconic carnivores.

The Government of Thailand in collaboration with WCS (Wildlife Conservation Society) established an intensive patrol system in in Huai Kha Khaeng Wildlife Sanctuary (HKK) in 2006 to curb poaching of tigers and their prey, and to recover what is possibly the largest remaining "source" population of wild tigers in mainland Southeast Asia.

Monitoring of the population from 2005-2012 identified 90 individual tigers and an improvement in tiger survival and recruitment over time.

"The protection effort is paying off as the years have progressed, as indicated by the increase in recruitment, and we expect the tiger population to increase even more rapidly in the years to come," said Somphot Duangchantrasiri, the lead author of the study."

To monitor the tigers, the scientists employed rigorous, annually repeated camera trap surveys (where tigers are photographed and individually identified from their stripe patterns) combined with advanced statistical models.

"This collaboration between WCS and the Thai government used the most up-to-date methodologies for counting tigers," said Dr. Ullas Karanth, a senior scientist with WCS and one of the authors of the study. "It's gratifying to see such rigorous science being used to inform critical conservation management decisions."

Analyses of the tigers' long-term photo-capture histories and calculations of tiger abundances and densities, annual rates of survival, recruitment and other information provided scientists with direct, comprehensive measures of the dynamics of the wild tiger population in HKK.

Joe Walston, WCS Vice President of Field Conservation said, "This is an outstanding conservation success coming from an area where wildlife has been struggling for some time. The result to date is reflective of the commitment made by the Thai government and its partners to Thailand's natural heritage. And despite the considerable gains made already, we believe the future looks even brighter."

The authors note that 10-15 years of intensive protection of source sites is required before prey populations attain optimal densities necessary to support higher tiger numbers.