downtoearth-subscribe

Terai damming away its wildlife

NEPAL'S Terai region seems hell-bent on courting environmental disaster. In the last 30-odd years wetlands and swamps have been reclaimed and massive rivers have been tied down by dams. The flood plain area has grown, while the sal and mixed forests have disappeared. By 1959, in the Chitwan valley alone, about 70 per cent of the forests and grasslands had disappeared and the human population had trebled from 36,000 to 100,000.

Explains Johannes J Bauer, in a study of Conservation and Development of Nepal's Terai Region, "Three river systems (Sun Kosi, Kali Gandaki and the Mahakali) have been modified. In the case of the Sun Kosi and the Mahakali rivers, it can be assumed that seasonal water availability, temperature, energy, sediment load and oxygenation have been entirely altered."

In the Kosi Tappu Wildlife Reserve, even the relict population of around 90 buffaloes is severely affected. And now, with negotiations complete for the Arun hydroelectric project, the future of Kosi Tappu appears bleak. The impact of a new irrigation project, estimated to cost US $37.9 million, on the Chitwan National Park, is still to be studied. But the park is already struggling to cope with ever-increasing tourist arrivals, related construction works, erosion of riverine forests, and illegal lopping of trees for timber.

Three major aquatic species, the Ganges dolphin, gharial and marsh mugger, are under threat in the four protected regions where hydel potential has been developed. As Bauer points out, "It seems more than accidental that the Mahakali river, which was modified 60 years ago, today has none of these species left, while the least modified Karnali is so far the only river with a full set of the three species."

As Bauer's investigations reveal, much of the Terai's animal population is increasingly being isolated. Even the sanctuaries and national parks are unable to halt the decline in populations, still less reverse the trend. Species like the sloth bear, Asian buffalo, Bengal florican, nilgai, Asian elephant, swamp crocodile, aquatic turtles, giant hornbill and the earth python are close to extinction. The Indian Chevrota, the pygmy hog and the four-horned antelope can now be found only in the pages of an encyclopaedia.

Bauer suggests that the Nepali authorities need to learn from the Tanzanian experience. Scientists working at the much-researched Serengeti National Park were perplexed at the massive fall in elephant, rhino and buffalo populations. An enquiry revealed: little of the research was ever applied, research implications were not expressed in ways which managers could understand and implement, and the social and human angle of conservation efforts were ignored. Unless development and conservation are integrated, wildlife could soon find itself without a future in the Terai.

Vegetation trends in Kosi Tappu wildlife reserve
Sal forest Riverine forest Grassland
Mixed forest Grassland
Riverine forest
Grassland Flood plain Flood plain
Flood plain
Past Present Future

Related Content