BENGALURU: The more recent method of tracking animals in the wild by using camera traps is only as good as the previously followed cost-effective method of identifying them based on footprints and fecal matter, new research has revealed. In fact, results of both types of surveys have been found to be nearly identical, paving the way for a mix of both methods in the future.The new studies were conducted by Wildlife Conservation Society-India Programme, the Centre for Wildlife Studies and the University of Florida-Gainesville.
Wildlife scientists point out that direct sighting of animals or from camera trap captures involve greater cost and effort. They studied sloth bears in Bhadra Wildlife Sanctuary employing the two methods for monitoring the distribution of the bears in the habitat. The sign survey was conducted along forest and plantation roads and intensively searched for fresh scats and tracks.The scientists felt that surveys of animal signs are more abundant and easier to find. These finding have important implications for conservation as animal sign surveys are a cheaper data source compared to direct detection methods.
The study (based on a long-term ecological study of tigers) was led by Wildlife Conservation Society scientist Dr Ullas Karanth and, for the first time, it provides a rigorous comparison of two different methods to estimate the proportion of a habitat occupied by sloth bears in a 754 sqkm area. “This study demonstrates the importance of using rigorous statistical methods in surveys of rare and elusive species to optimise the quality of results as well as efficiently use substantial investments being made in such surveys now,” said Karanth who co-authored the study.
According to Arjun Srivathsa, lead author of the paper, sloth bears were chosen as a study species as they offered clear advantages in ensuring no false positive detection. In fact, photos of sloth bears from camera-trap surveys and indirect signs of the species are unmistakable.