The Straight Poop
June 18, 2009
You can count a tiger by its stripes, and now, in the latest breakthrough in the science of saving this endangered big cat, you can count it by its dung. Wildlife Conservation Society scientists are using high-tech fecal sampling to tally and assess tiger numbers. Tiger scat provides a unique DNA signature that allows researchers to accurately identify individual animals.
In the past, DNA was collected from blood or tissue samples from tigers that were darted and sedated. The authors of a new study say this advanced, non-invasive technique represents a powerful tool for measuring the success of future conservation efforts.
The study appears in the June 16th edition of the journal Biological Conservation. Authors of the study include: Samrat Mondol of the National Centre for Biological Sciences; K. Ullas Karanth, N. Samba Kumar, and Arjun M. Gopalaswamy of WCS and the Centre for Wildlife Studies; and Anish Andheria and Uma Ramakrishnan, also of the National Centre for Biological Sciences.
“This study is a breakthrough in the science of counting tiger numbers, which is a key yardstick for measuring conservation success,” said noted WCS tiger scientist Dr. Ullas Karanth. “The technique will allow researchers to establish baseline numbers on tiger populations in places where they have never been able to accurately count them before.”
The study took place in India’s Bandipur Reserve in Karnataka, a long-term WCS research site in the Western Ghats that is home to an abundance of tigers. Researchers collected 58 tiger scats following rigorous protocols, then analyzed their DNA. Tiger populations were then estimated using sophisticated computer models. These results were validated against data from camera traps, which remotely photograph individual tigers and allow researchers to identify the cats by their unique stripe patterns. Camera-trapping is considered the gold standard in monitoring tiger populations, but is difficult to implement in areas where tiger densities are low, or field conditions too rugged.
“We see genetic sampling as a valuable additional tool for estimating tiger abundance in places like the Russian Far East, Sundarban mangrove swamps, and dense rainforests of Southeast Asia where camera trapping might be impractical due to various environmental and logistical constraints,” said Karanth.
WCS has been engaged in saving tigers in the Western Ghats in association with the Indian government and several local conservation partners for more than two decades.