Journal Article

2014

Koustubh SharmaBelinda WrightTito JosephNitin Desai

Tiger poaching and trafficking in India: estimating rates of occurrence and detection over four decades

Poaching, prey depletion and habitat destruction have decimated the world’s wild tiger population tofewer than 3200–4000. Despite focused efforts, poaching continues to be the key threat to tiger populationsin India, home to more than half of the world’s tigers. A rise in the number of incidences of tigerpoaching and trafficking may not essentially represent an increase in the actual occurrence of tigerpoaching and trafficking, but can instead be an indication of better enforcement. With ad hoc detectionrates, it becomes difficult to estimate the true quantum of poaching and the efficiency of enforcement.We empirically estimate the probability of occurrence of tiger crime and that of detecting it during periodsof 3–7 years in the past 40 years in the 605 districts of India. We test the hypotheses that tiger crimeis influenced by the presence of tiger trade hubs, proximity to a number of tiger habitats, and that tigerpoachers prefer to use rail routes over road highways. The annual probability of detecting tiger crime wasestimated to be highest (0.46, 95% CI = 0.38–0.54) in the period between 1993 and 1995. Our results identify73 districts as current tiger crime hotspots with high (>0.5) probability of occurrence of tiger crime.We propose that the probability of occurrence of tiger crime can be a more reliable estimator of changingpoaching pressures and that probability of detecting tiger crime provides a robust estimate of the efficiencyin tackling tiger poaching and trafficking.

Biological Conservation, doi: 10.1016/j.biocon.2014.08.016