The data collected will be used for tabulating the tiger census programme in the country.
As part of the tiger census programme, for the first time 506 camera traps have been set up in a 925 sq-km area of the Periyar Tiger Reserve, one of the single largest compact forest blocks in south Western Ghats, to intensively monitor the population of the feline.
The reserve has been divided into 253 grids, with each grid covering an expanse of four sq-km and having one pair of camera.
The programmed started today, Deputy Director PTR Krishan Kumar said, adding that 506 camera traps have been put up at the reserve.
"This is the first time that this exercise is being done on such a large scale in the Tiger Reserve," he told PTI.
The data collected will be used for tabulating the tiger census programme in the country, which is done once in four years, he said.
Camera trapping exercise is normally done twice a year, one before the start of Sabarimala pilgrim season in November-January and another during March-April.
But this is the first time the entire reserve has been covered, Mr Kumar said.
The photographs using camera traps will be segregated after a one month period ending on November 17.
"We will extract the images from the cards, segregate the images and tiger analysis will be done and we will know how many have been captured in the cameras during the exercise," he said.
The exercise is to help keep track of the animals. "We have a data base. This is to monitor the tigers, preys, leopards, sambars, porcupines and such other animals," he said.
The strength of the tigers in PTR is believed to be around 35-40. The photographs of tigers which have been captured in the cameras will be monitored.
Each tiger has different pattern of stripes, like finger prints of humans, and identification is done on the basis of their stripes, he said.
The report will be handed to the National Tiger Conservation Authority.