19 October : Tiger population at the famous Periyar tiger reserve (PTR) in Kerala’s Idukki district has increased from about 22 in the past to 38 with cubs constituting around 25 percent of it.
Due to stringent protection measures adopted by authorities at PTR, the density of tiger population has also gone up, a recent survey done using innovative camera trap techniques found. Tiger density, estimated at 3.4 tigers per 100 sq km in PTR, dominated with evergreen forests, is comparatively higher than similar habitat types such as Bukit Barisan (1.6 tigers) and Taman Negara (1.7 tigers) in Malaysia and Huai Kha Khaeng (2.2 tigers) in Myanmar.The survey through capture-recapture technique using camera traps covering 640.7 sq km was carried out by Conservation Biologist M Balasubramaninam and Ecologist A Veeramani of Periyar Tiger Foundation, Thekkady, between January and May 2008.
"We deployed 56 cameras in four-trapping blocks -Thekkady Range, Vallakdavu Range, Periyar Range and Periyar West Division," Balasubramaninam told a news agency.
A total sampling effort of 840 trap-days yielded 45 photos of 18 individual tigers over 15 sampling occasions.
Of the 18 identified animals, Theddaky and Vallakadavu ranges were seen with seven each, while three were in Periyar Range and one in West Division.
Of the 18, six were males, he said.
The photo capture probability and sample showed an estimated population size of 24 tigers and a density of 308 tigers in 100 sq km,Balasubramaninam said.
The tiger population has been estimated using the above sampling method at deciduous and grassland region in PTR.Studies showed that cubs accounted for 25 percent of the total population in the 925 sq km of PTR, he added.
On the survey method adopted, he said the results suggested that camera-trap technique was more effective and reliable in monitoring the tiger population in PTR.
The survey revealed PTR as a low-density region mainly due to the evergreen dominated landscapes resulting in low prey-base.
He said nearly 5,400 local families were actively involved in the conservation project, under the co-Development Committees (EDC) formed ten years back by the Forest department.
"Interestingly, some of the members of the EDCs were poachers-turned-conservationists and their contribution now for the protection of wildlife is very valued," he said.
For better protection and conservation of the PTR, it was recommended that adjacent forest areas, including stretches in Tamil Nadu, should be managed appropriately by declaring it as a buffer zone.
The area between Kalakkad-Mundanthurai and Periyar Tiger Reserves should be well connected by establishing a corridor at Aryankavu Pass to facilitate genetic exchange for long-term survival of the wildlife population, he said.