Captured tiger had highest home range, says expert

Captured tiger had highest home range, says expert

Realignment of highways in forests will prevent big cat deaths

Captured tiger had highest home range, says expert

The recent capture of a ‘man-eating’ tiger at Bommalapura hadi in HD Kote taluk in Mysore district (near Nagarahole Tiger Reserve) makes a case, once again, to defragment critical wildlife habitats.

The tiger, according to wildlife experts, had a home range larger than any in its species. It was frequently spotted on the Mysore-Mananthavadi highway as camera trap evidences show.

Sanjay Gubbi, a wildlife biologist and member of the State Board of Wildlife, during his research on the impact of vehicular traffic on wildlife along the Mysore-Mananthavadi highway had camera-trapped the tiger, now housed at the Mysore zoo, twice on  December 6, 2009 and on December 17, 2009 at Kalhebballa and Yeradane Mori, respectively, along the highway.

“Camera traps of the tiger have confirmed that this one had the longest home range of 17 km (aerial distance). In addition to this, we had pictures of the animal taken by some journalists on the same road. When we compared those pictures with pictures taken by us, it was established that it is the same tiger,” Gubbi told Deccan Herald.

Noting that the tiger, when camera-trapped, was a large, healthy male in its prime, he said that such big cats need uninterrupted home ranges to enable their survival for a long time.

The finding establishes that fragmentation of their habitats by linear intrusions (highways) has both a direct and indirect impact, which affect their behaviour, movement patterns and other ecological factors.

“This will also disrupt the genetic viability and dispersal of tigers. Vehicular traffic within tiger reserves also poses the risk of tiger mortalities due to speeding vehicles. Hence, avoiding highly disastrous highways in ecologically sensitive areas such as tiger reserves is very important,” he said.

The episode highlights the need for making tiger habitats free of fragmentation threats such as highways. Even the National Wildlife Action Plan drawn up under the chairmanship of the prime minister has suggested that highways should be realigned outside national parks and wildlife sanctuaries.

“The movement patterns of this tiger recorded by us depicts the value of realignment of this highway done by the government,” says Gubbi.

The scientist said there was a probability of tigers with large home ranges, such as the one captured by the forest department, crossing highways several times during their lifespan, thus increasing the chances of being killed by speeding vehicles. He pointed out that the Nagarahole Tiger Reserve had four major roads passing through it.