The tiger census held in 1997 estimated the number of adult Bengal tigers in the Bangladeshi part of the Sundarbans to be 362. On the other hand, according to the same tiger census held that year, the number of adult tigers in the West Bengal part of the forest was 263.
The Bangladesh part of the forest is about two-thirds of the total forest area, of about 10,000 square kilometers (about 6213 square miles). The Sundarbans is the largest mangrove forest as well as the largest home to wild tigers in the world. In this forest, the density of the tiger population is the highest in the world.
There are four indirect techniques to count tigers in a forest: The pugmark technique, scratches on trees, radio tracking (or radio-telemetry technique) and camera traps. Among these four techniques, the first one is frequently used, especially in the Sundarbans, for conducting a census. This technique is based on impressions of pugmarks left on the ground by tigers.
Walking in this forest, even for a short distance, is impossible without coming across pugmarks of a tiger. Tiger pugmarks may stay unaltered for about two weeks, but a fresh pugmark can be differentiated from an old one. An experienced person can tell how old the pugmark is.
The pugmarks of one tiger are distinguishable from those of another. Hind pugmarks are used for the purposes of a census, because the front pugmarks of both male and female tigers are almost square in shape; but the hind pugmarks of a male tends to be square, and rectangular for females. This difference in the shape of pugmarks helps in counting male and female tigers separately.
Pugmarks of a tiger cub under six months of age may be confused with that of a leopard. But as a tiger cub always moves with its mother, a small pugmark unaccompanied with bigger ones can be taken as that of a leopard.
The depth of the pugmark on the ground helps determine the weight of a tiger; and the distance between the pugmarks of the hind and front legs helps to get the measure – from the tip of the nose to the tip of the tail – of a tiger. The forests in other parts of India, except the part of the Sundarbans in West Bengal, are home to around 3,750 Bengal tigers. In Bhutan, this subspecies of tigers counts at around 240. There are 230 in Myanmar, 220 in Nepal, and 35 in China. Out of 5,000 zoo tigers around the world, 4,000 are Bengal tigers.
If we count all these figures together, we find that the present Bengal tiger population in the world is around 9,000. Only at the turn of the 20th century was their number about 100,000. Of them, 40,000 probably used to live in the South Asian subcontinent. The condition of the other subspecies of tigers, from the viewpoint of their numbers, is much more miserable.
To date, the surviving Chinese tigers count at less than 30, and Siberian tigers, found in Russia, China and, North Korea, are at no more than 400. Tigers seen in the vast tracts of China, Cambodia, Laos, Malaysia, Myanmar, Thailand, and Vietnam tally up to around 1,780. Of the eight subspecies of tigers, three – the Balinese tiger, Caspian tiger, and the Javanese tiger – have become totally extinct in the 20th century. The way the number of tigers has been decreasing in the Sundarbans, soon this natural habitat will have no tigers at all.
This article was first published in Dhaka Tribune, Bangladesh’s leading newspaper. Click here to go to the original.