'Make conservation planning part of road development'

From a socioeconomic perspective upgradation of surface transport system is a key element for economic development. This is one of the important fields that has been given emphasis in India’s rapid economic progress.

Betterment of roads also leads to the increase in number of vehicles on road that are growing at a rate of 10 per cent per annum. Several international donor and lending agencies are providing economic impetus for the expansion of road network. No one would argue against the road development. However caution needs to be exerted with the location of some of the road projects.

For example, of the 15 national highways in Karnataka nine pass through important wildlife habitats in the Western Ghats, while parts of the 28 state highways of the total of 151 pass through the Ghats. This road development in biologically sensitive areas will have a serious impact on wildlife. They affect ecosystems, biological communities and species in numerous ways.

Roads, especially highways, can have significant impacts on wildlife behaviour, survival and movement of animals by acting as physical barriers. This is especially true for wide-ranging, ecologically sensitive large mammalian species such as the tiger, wild dog, lion-tailed macaque to name a few. One of the worst affected taxa are tree dwelling primates and rodents. With breakage in canopy these animals get isolated to smaller patches. Roads fragment and isolate wildlife populations thus affecting genetic diversity of the populations.

These are not claims of a few breast beating wildlife enthusiasts; science has clearly documented the effects of roads. In the Russian far east, systematic studies by Linda Kerley of the Hornecker Wildlife Institute and her colleagues have documented that roads decrease the survival and reproductive success of the highly endangered Siberian tigers. Grizzly bears and wolves shift their home ranges away from areas with high road densities. Studies by renowned road ecologist William Laurance have proved that elephants in Gabon preferentially located themselves to forests away from roads.
Altering physical environment, aiding the spread of exotic plant species such as eupatorium, parthenium, spread of pathogens, and increase in passive harassment of animals are some of the other negative ecological impacts of roads.

The most serious and obviously seen impact is mortality due to road kills. For some wildlife species a combination of poor eyesight, slow movement and over speeding of vehicles leads to mortality both in the lower taxa and larger animals. Such unnatural mortalities can have deleterious effects on a population through loss of breeding individuals especially in apex, wide-ranging wildlife that have low reproductive rates.
Vehicular collision is one of the primary causes of death to endangered species like the Florida panther. Wildlife mortalities in Bandipur tiger reserve due to speeding vehicles are so high that it led to the high court of Karnataka to close the roads for night time traffic. Roads will also facilitate increased use of the area by humans including for illegal activities such as timber smuggling and wildlife poaching.

Some of these impacts may be reduced if speed calming and other mitigation measures are scientifically implemented. Wildlife crossing structures can increase permeability and habitat connectivity across roads. However closure of highways at night is the best mitigation measure as it is practiced in other parts of the world.

Karnataka hosts some of the best protected areas for tiger and Asiatic elephant conservation with Nagarahole and Bandipur tiger reserves holding some of the highest densities of these endangered wildlife acting as important source populations.
Anshi-Dandeli tiger reserve, Kudremukh National Park, Someshwara, Mookambika Wildlife Sanctuaries and other reserved forests in the Western Ghats act as important sink or dispersal corridors for these extinction prone wildlife species.

However new roads or upgrading existing roads to high-speed highways have been proposed in some of these critical wildlife habitats. The Londa-Karwar highway (SH 95) will cut through the heart of the Dandeli-Anshi tiger reserve, the Karkala-Sringeri (NH 13) and SK Border-Kudremukh (SH 66) highways, Agumbe ghat road (SH 1) and Kollur-Nagodi road will all further slice the last remaining lion-tailed macaque habitats in Karnataka.
Although important for economic development, poor planning, non-integration of wildlife conservation and excessive road expansion into wildlife habitats will cause irreplaceable damage to wildlife in the longer-term. No one opposes development. But, Karnataka with only 3.3 per cent of its land area under protected area category should expand, rather than further fragmenting its last remaining wildlife habitats. Integrated conservation planning that provides long-term solutions for reducing impact of linear intrusions like roads on wildlife needs to be developed for the state.

The much acclaimed night traffic ban through Bandipur tiger reserve has been a critical move for wildlife. The journey bypassing the tiger reserve will cost only a few rupees. This will also ensure that the cost of conservation is also borne by city dwellers, who want to visit or pass through nature areas.
(The writer is a wildlife biologist and a member of State Board for Wildlife)