The good news is there are tigers in the Buxa Tiger Reserve (BTR) in West Bengal. But, the worrying part is the scarce prey-base for the national animal. Net result is that the few big-sighted cats roaming are only a floating population.

In a DNA-based survey, it has been established that at least 12 to 14 tigers frequent the 800-square km reserve. However, the concern is they are not resident. Secondly, the gender ration is skewed, with very few (3-4) females, says the work done by Hyderabad-based LaCONES Lab of the Centre for Cellular & Molecular Biology (CCMB).

There is vast forest area around the BTR, with the Jaldapara wildlife sanctuary in the neighbourhood. Further, the adjoining border regions with Bhutan offer rich forest cover. For the tigers to thrive there is a need for a good population of deer and other animals in the forest.

The CCMB researchers took up the study following the request of the forest department of West Bengal, which in turn was told by the National Tiger Conservation Authority that the tiger density in the BTR was very low. They obtained faecal samples from the forest department and did DNA analysis during the period 2010-14.

Breeding issues

According to Anuradha Reddy, lead researcher who does extensive work on the population genetics of tigers in the country, the tiger population was also not a stable breeding group and the males were moving between forests using the Buxa-Assam corridor, which extends into Bhutan.

Interestingly, in Central India and Western Ghats, number of females were comparatively higher.

Talking to BusinessLine , she said urgent steps and conservation measures were required to ensure that the big cats make the BTR their home and reduce conflicts with humans. For example, in the Tadoba forest region of Chandrapur in Maharashtra, around a dozen human deaths have been reported in recent years due to this conflict.

A few years ago, the CCMB lab had also conducted a project in the Central and South Indian tiger reserves a few years ago. Their findings that four tigers (three males) were sighted in the Kawal region of Adilabad, Telangana, was used as a key evidence to declare around 1000-square km area as the Kawal Tiger Reserve, she said.

However, the tigers keep moving from the Chandrapur-Gadchiroli side of Maharashtra. With the prey-base being very poor, the survival of the tigers is at stake. Efforts such as trans-locating tigers has not really been effective.

Hence, in several reserve forest areas, there is an immediate need to improve the incentives for the tiger to reside and thrive. The small rise in tiger population reported after every four-year census in the country alone is not enough.