The population of Indian tigers has increased according to one of the detailed wildlife surveys conducted. The number has increased by 6% bringing up the total to roughly 3000. This huge survey may set a record in the counting of large carnivores. The results reflect India’s investment in the conservation of tigers.
Large predators do not want to be seen. Their whole existence revolves around avoiding prey detection and sneaking close before an attack. So, tigers don’t help in their counting. However, correct numbers are important for proper conservation. Since 2006, Government of India conducts a national census of tigers and other wildlife animals every four years. 44,000 field staff conducted nearly 318,000 habitat surveys in 20 states in India which are tiger occupied. A total of 381,400 square kilometres was checked for tigers and their prey. An application has been filed with the Guinness Book of World Records to check if this is the largest wildlife survey ever conducted in the world.
Camera traps were placed at 26,760 locations across 139 study sites which took nearly 35 million photos of which there were 76,523 tiger and 51,337 leopard photos. These covered nearly 86% of the tiger distribution in the country. In the remaining 14% where it was dangerous to work due to political reasons, population numbers were estimated by robust models.
This volume of data collection needs proper analysis. Teams took advice from experts for sorting the photos. Pattern matching experts identified whether a photo taken in monsoon matched the one of the tiger taken in dry season walking at a different angle. Machine learning experts increased the pace of identification of species while spatial analysis experts estimated the population of tigers and their prey. The research team took this help along with their own knowledge of tiger ecology to create a unique census for large carnivores.
A total of 2461 individual tigers aged more than a year were photo-captured. The total tiger population in India was estimated to be 2967 with an error margin of roughly 12%. Among this, 83.4% were estimated from camera photos and the others using robust modelling. The tiger population increased at 6% per year, continuing the trend from 2014 which depicts the success of Indian conservation.
However, there has been a decline of 20% in areas occupied by tigers from 2014, although tigers have moved to some new areas which is 8% of the Indian range. Coordinators of the survey, Yadvendradev Jhala and Qamar Qureshi stated that secure and established tiger populations in some parts of the nation have increased and small, isolated counts between the corridors of the established population have gone extinct. This brings up the issue of conservation to improve the connectivity between isolated populations also relocating the people out of core tiger areas and decreasing poaching and improving the habitats to better the prey resources.
Achieving this needs investment from the private sector tourist corporations for acquiring land in the corridors and creating community conservancies to supplement the government funding. India’s success has led Nepal and Bangladesh to employ the same project team for their own tiger populations. These techniques should be used for species which can be individually identified such as jaguars, leopards, cheetahs.