Today is International Tiger Day and dispersal is integral to the life history of tigers. But several factors, including infrastructure projects, fragment tiger corridors thus impeding tiger movement. Maintaining habitat connectivity to enable dispersal is arguably the most pressing imperative for tiger conservation today.
Though infrequently documented, dispersal is integral to the life history of tigers.
In April 2018, a young male tiger with a radio collar slipped across the border between Uttar Pradesh and Nepal and embarked on a circuitous journey through farmlands, settlements, forests into the remote Churia hills. A few years before, a radio-collared tigress threaded her way from Madhya Pradesh’s Panna Tiger reserve to Uttar Pradesh’s Ranipur Wildlife Sanctuary, similarly negotiating diverse land use types.
More recently, in the summer of 2019, a young tiger was photo-captured on a camera trap near tree-line Kedarnath Wildlife Sanctuary in the Uttarakhand Himalayas, about 100 kilometres away from the nearest known population from where this animal possibly originated.
Though infrequently documented, dispersal is integral to the life history of tigers. Dispersal fosters greater genetic vigour in populations and ultimately enables species to persist in fragmented landscapes. Maintaining habitat connectivity to enable dispersal is arguably the most pressing imperative for tiger conservation today.
While India has successfully fostered tiger population recovery in some areas and sustained robust source populations in others, about 70 per cent of the species’ extant habitat in the country is still largely bereft of tigers, and other areas only support the species’ at low densities.
This situation can be remedied in many areas through sustained efforts to strengthen protection and by garnering community support — so long as habitat tracts remain. Such efforts to promote tiger population recovery are likely to succeed where functional corridors exist, and conversely become prohibitively difficult and costly with the degradation of corridors by the combined effects of land use change, linear infrastructure, and urbanisation.
Recent studies have cast light on factors that impede tiger movement in corridors and the long-term impacts of fragmentation on animal movement and wildlife populations.
India already has the highest road density within tiger habitats. By 2050, road development within tiger landscapes in India is projected to increase by 14,000 km, several orders of magnitude higher than other tiger-bearing countries.
Other research reveals that while tigers have the propensity to move through agriculture and plantations, roads with high traffic volume and dense settlements are significant barriers to movement. Roads are thought to have depressed numbers of tigers and other wildlife by their ungulate prey by as much as 20 per cent across the specie’s range, and adversely affected survival in some areas.
Projections from some recent studies suggest that under future scenarios of land use change and infrastructure development will drastically increase extinction probabilities of tigers in small and isolated habitat patches.
Road and linear infrastructure is clearly a pressing development imperative, but it must not be a foregone conclusion that infrastructure development will come at the cost of wildlife habitats. Reconsidering the location, width and other specification of roads, considering realignment and building in appropriate mitigation measures can mitigate their impacts.
While such measures and alternatives are considered, they are often afterthoughts, and sometimes viewed as costly excesses impeding development.
There is something to be hopeful about too. Growing evidence of the ability of tigers and other wildlife to move through agro-ecosystems suggests that ecological connectivity for some wildlife species can still be maintained in some landscapes where forested corridors are absent or degraded. But corridors in agriculture-forest mosaics will only remain permeable for wildlife movement if they are buffered from poorly-planned land use change, urbanization , mining, industrial development and accelerated road and highway development.
Given that there is no national land use policy in India, and that corridors lack legal recognition and their location, extent, boundaries are often shrouded in ambiguity, it is often hard to strategically reconcile conservation and development planning. Yet, some critical actions must be prioritised to strengthen connectivity conservation.
Rigorous surveys to delineate corridors and assess their functionality must be brought to bear on infrastructure projects and land use planning. In parallel, conceiving and operationalizing mechanisms to finance incentives for farming communities that will enable them to maintain agricultural and land-use practices that provide safe passage for tigers and other wildlife will help maintain connectivity into the future.
These and other actions and policies need to be designed and steered under the aegis of a specially appointed committee with representation from multiple ministries, the planning commission, academic institutions and civil society groups. Solutions should empower marginalised communities living in and around wildlife corridors given their strong ties to forests.
Finally, decisive legal action, such as the Supreme Court order to remove barriers in an elephant corridor in South India, will lend great strength to connectivity conservation initiatives.
India’s population is projected to grow by nearly 300 million people between now and 2050, and pressure on land and corridors will only increase dramatically. Unless we act decisively and soon to protect and restore corridors, the species then faces the prospect of being consigned to besieged forest fortresses and within which some populations will spiral towards extinction.
Pranav Chanchani is national lead for tiger conservation at the World Wide Fund for Nature, India (WWF India). He provides technical leadership to a team of about 25 biologists in six tiger conservation landscapes within India. Views are personal.