Kerala to estimate wild elephant and tiger populations

Kerala to estimate wild elephant and tiger populations

Subject: Environment

 Section: Species in news

Context: The Kerala Forest department is set to launch surveys to enumerate wild elephant and tiger populations as part of its efforts to mitigate man-animal conflict in the State.

Tiger census

• The national tiger census is conducted once every four years.
• The Nation-wide tiger census was earlier held in 2006, 2010, 2014, 2018.
• The National Tiger Conservation Authority (NTCA) conducts tiger censuses in partnership with state forest departments, conservation NGOs, and the Wildlife Institute of India (WII).
• Census methodology
  • Double sampling based on ground-based surveys and actual images captured on camera-traps.
  • Double sampling method was introduced in 2006 after the “pugmark” surveys were found to be inaccurate.
  • In 2018 census, 83% of the big cats censused were individually photographed using camera traps.
  • In Phases 1 & 2, ground-based surveys were carried out by Forest Department officials to collect signs of tiger presence like scat and pugmarks.
  • In phase 3, the information was plotted on the forest map prepared with remote-sensing and GIS (MSTrIPES).
  • In the last phase, data were extrapolated to areas where cameras could not be deployed.

Elephant census

• Elephant numbers largely rely on States directly counting the number of elephants.
• Elephants are counted once in five years.
• Census methodology
  • The direct elephant counting method is based on sightings of elephants.
  • In the indirect method, surveyors follow a dung decay formula for arriving at population estimation which is being used by Tamil Nadu and Karnataka at present.
  • A variation of about 8% to 9% has been noticed between the two methods.