Stress takes a toll on tigers in Sariska

Study says human disturbance affecting breeding in Reserve.

Tigers reintroduced in the Sariska Tiger Reserve in Rajasthan between 2008 and 2010 have been producing fewer offspring.

High stress levels in tigers, caused by human activity, have affected their breeding in the Sariska Tiger Reserve in Rajasthan, a study says.

Tigers were reintroduced in the Sariska and Panna tiger reserves after poaching, habitat loss and prey depletion made them extinct in those protected areas. As part a species recovery programme, tigers were reintroduced between 2008 and 2010 in Sariska and 2009 and 2013 in Panna.

While the reintroduced tigers have given birth at regular intervals in Panna, it is not so in Sariska, though the tigers have been mating. This led to a study by scientists from the Laboratory for the Conservation of Endangered Species (LaCONES) of the CSIR-Centre for Cellular and Molecular Biology (CCMB); the Wildlife Institute of India (WII), Dehradun; and the Endocrine Research Laboratory, Department of Anatomy and Physiology, University of Pretoria, South Africa.

Govindhaswamy Umapathy from LaCONES, in collaboration with Kalyanasundaram Sankar of the WII, studied the stress responses of the reintroduced tigers in relation to human disturbance. They used a non-invasive approach to study stress by monitoring faecal glucocorticoid (fGCM) metabolite concentrations in the tigers over 18 months and collected 120 samples. It was found that 80 per cent of the 881-sq.km Sariska reserve had some kind of disturbance, such as livestock movement, woodcutting and human and vehicular movement, elevating fGCM concentrations in the monitored tigers.

Dr. Umapathy says prolonged stress might have affected reproduction. The study recommended regulation of vehicular traffic, shifting of artificial waterholes away from tarred roads and relocation of eight villages from the core area of the reserve.

The relocation has been due since 1984. Once that is done, an inviolate area of 300 sq.km will be available for breeding, the study noted.

CCMB Director Ch. Mohan Rao says reproductive studies in endangered species are immensely useful in developing breeding protocols and creating stress-free habitats for tigers and other wild animals.