The Terai Arc Landscape Project (TAL) - Rhino Count

A scientific census in a challenging terrain

To conserve an endangered species, it is important to determine the number of animals, and whether that number is increasing or decreasing. For this purpose, the rhinos of Chitwan National Park - the world's second largest population of the greater one-horned rhino - are counted every 5 years.

This can be done by counting a few samples in typical areas and extrapolating the total figure of the population from that. But in this case, that will not do.

"When the population of the species is small, it is really important that the counting method is a total count, in order to get reliable numbers", says Jhamak Karki, Assistant Ecologist from the Department of National Parks and Wildlife Conservation, who was the coordinator of the technical part of the Rhino Count 2005. The Count was also co-supported by King Mahendra Trust for Nature Conservation.

Through jungles and tiger habitats
"There have been rhino counts here in 1994, 2000, and now 2005. The method is the same, making figures comparable", Karki says. The method, scientifically validated by biologists, involves systematically combing through all rhino habitats and recording the sex, approximate age, and individual markings of each rhino that is been seen, as well as date, time, and location.

Nepal is the only country in Asia to use this method. The great advantage of the method is its preciseness. Recording individual markings enables the comparison of all the different sightings with each other, revealing instances where the same individual has been sighted twice.

But combing through most of the 968 square kilometres of the park, plus the surrounding buffer zones is easier said than done. Inside the park, the jungle is often too dense to enter with a jeep, and the presence of tigers makes walking too dangerous. The only way to make this possible is to use tame elephants, and experienced riders and counters.

"In the count 2005, there were 25 elephants moving parallel to each other", Karki explains. "The distance between them depends on the sightings between the two elephants in the rows. This is largely determined by the presence of vegetation in the site. For example in grassland the sighting between the two counting elephant is highest and therefore the distance between them is maintained about 150-200 m. In a dense forest it is less, maybe 50 m. When the crew observes a rhino, the two nearest elephants move closer together, and individual markings of the rhino are recorded. Then they move ahead again, to let the rhino pass."

For some of the people working in the 2005 count, this was already the third time. Even though some of the local participants are illiterate, they know every aspect necessary to carry out this operation.

Time to bring them back again
"From the 1994 to 2000, the rhino population in Chitwan National Park had grown by 3.8%", Karki says. In the count of 2005, however, the news was grim. As was expected, the ongoing insurgency had taken a heavy toll on rhinos, and the population had shrunk by a third.

The number of rhinos in the park had dropped from 544 in 2000 to 372 today. Without the anti-poaching measures that have been implemented actively by the park, with the financial and technical support from the TAL project, the numbers would have fallen a lot more sharply.

As long as there are rhinos, there is hope. "We brought Nepal's rhinos from the brink of extinction once, and we will do it again, with the joint effort of conservation partners from around the world," says Dr. Chandra Gurung, Country Representative for WWF Nepal.