The Sundarbans tiger: adaptation, population status and conflict management.

Abstract

The Sundarbans of India and Bangladesh is the only mangrove in the world where tigers still live. The Sundarbans is of relatively recent origin and has gone through substantial changes over time, driven by sea level changes, sedimentation, neotectonics, climate change, and human use. The area is of great economic value, provides essential ecosystem services, and is deeply embedded in the culture of the region. The Sundarbans has been under various forms of management for about 2,000 years, and is classified as a Tiger Conservation Landscape of Global Priority. Little is known about the Sundarbans tigers, which are threatened by habitat destruction, prey depletion, and direct tiger loss. This goal of this study was to increase understanding of tiger evolution, population status, and human-tiger conflict. Skulls and body weights of Sundarbans tigers were found to be distinct from other subspecies, indicating that they may have adapted to the unique conditions of the mangrove habitat. Female home ranges, recorded using Global Positioning System collars, were some of the smallest recorded for tigers, indicating that the Bangladesh Sundarbans could have one of the highest densities and largest populations of tigers anywhere in the world. A survey based on tiger track frequency along creek banks in the Bangladesh Sundarbans showed that tigers are still present throughout the landscape, but that abundance is variable. A monitoring program based on this technique has a reasonable power to detect future change in tiger abundance. A review of human-tiger conflict data showed that the number of tiger and human deaths has declined in recent decades. A management framework was developed to support activity selection for the mitigation of human-carnivore conflict, and was applied to human-tiger conflict in the Bangladesh Sundarbans. Collaring problem tigers and creating teams to respond to tiger attacks were identified as the most cost-effective means to reducing the conflict. The monitoring program allows managers to evaluate the effectiveness of conservation strategies. The activity selection framework supports decision-making for the mitigation of human-carnivore conflict. This study highlights the Sundarbans as a high priority area for tiger conservation, and the information collected has been used to help create a national tiger action plan.