Population of tigers in the Sathyamangalam forest in the district has risen to 28 in 2011 as against 18 in 2009, a census by forest officials stated.
Forest officials said in 2007, there were only eight tigers. The number declined to seven in 2008 but increased to 10 in 2009 and at the end of that year there were 18 big cats in the area. In 2011, the number increased by 10.
"Camera trapping technique was followed in detecting the number of tigers," they said.
The number of elephants has increased from 815 in 2007 to a little over 900 in four years.
Officials said it was proposed to dig 75 km long trenches in Erode and Sathyamangalam forest divisions following complaints from farmers that elephants were entering their lands and damaging standing crops like banana, coconut and other fruits.
Strict vigil is being maintained to prevent poaching, they added.