Chasing the blackbuck

MAIN CAUSE Human-related factors seem to be the biggest impediments to the peaceful existence of certain species like the blackbuck, writes Ananya Jana

Ask any person from a big city and they will tell you how house hunting is one of the biggest banes around. Now if you thought that was difficult, try and surmise the perils of house hunting that fall upon an animal. Animals have to search for a ‘house’, or habitat, with good nutritious food resources while evading dangerous predators and other risks. Plus, in a country like India, the seasons keep changing, with some foods available at some times, and water sometimes scarce. Animals have their task cut out to decide which habitat they should use at a given point of time. In recent times, they have an additional layer of complexity: the conversion of their natural homes for urbanisation and development. In the face of so many factors, finding a liveable habitat becomes a challenge.

A study published in PLOS ONE by a team of researchers from the Centre for Ecological Sciences at the Indian Institute of Science, Manipal University, Centre for Wildlife Studies and the Wildlife Conservation Society-India, attempted to understand how blackbucks navigate a landscape with changing resources, while running the gauntlet of competing livestock, humans and Indian wolves.

The blackbuck is a near threatened antelope species, closely related to the graceful African gazelle. It is medium sized, about the size of the common spotted deer. The blackbuck lives in groups, is a grazer, and is endemic to the Indian subcontinent. Male and female blackbucks look very different from each other. The females are fawn-coloured and mostly hornless, while males range in colours from dark brown to a beautiful velvet black, with white undersides, white patterns on their faces and striking spiralled horns.

Natural proclivity

The blackbuck prefers wide, open spaces, where they can sight their natural predators from afar and escape. They occur in a special type of habitat which can be found throughout India: the semi-arid landscape, characterised by open grasslands that are also inhabited by the critically-endangered Great Indian Bustard and the Indian wolf. Unfortunately, the general perception among forestry officials is that grasslands are ‘wastelands’; the tendency is to plant trees, which modify the landscape of its intrinsic open nature.

The Great Indian Bustard Sanctuary, in Nannaj, Maharashtra, is one of the few sanctuaries where this kind of habitat is being protected. Thanks to the increasing encroachment by humans, the sanctuary is fragmented into patches of protected areas interspersed with plantations, unprotected livestock grazing areas and agricultural lands, which in turn are frequently razed by the blackbucks themselves. The sanctuary presented itself as an ideal location for the researchers who wanted to study how blackbucks find new ‘homes’ under changing conditions. The landscape is densely populated by both humans and cattle. Funded by the Ministry of Environment, Forests and Climate Change and the Royal Norwegian Embassy in New Delhi, this study examined how blackbucks reacted to living in this habitat, which is representative of most semi-arid landscapes in India.

The researchers measured the quality of grass, which is the major food source for blackbucks, and identified the areas of risk, where the blackbucks were most likely to come across wolves, dogs or humans. They found that blackbucks preferred to stay in the safety of the sanctuary when food quality was high, to avoid the risk of encountering predators. A surprising result was that blackbucks did not seem to choose their habitat ‘homes’ based on grass quality. This was surprising since blackbucks are largely specialised grass-eaters, a resource that is of relatively low quality for most of the year in arid lands, and hence the quality of their food resource was expected to be influential in habitat selection. Other studies have shown that other antelopes and deer, on the other hand, selected their habitats depending on grass quality.

Man-made obstacles

The main factors affecting a blackbuck’s househunting decision, was human-related activities. The risk to blackbucks seemed not only due to their natural predators – the Indian wolf – but also the presence of humans, dogs and livestock. Thus, apart from food availability, blackbucks preferred areas of less risk. This habitat choosing mechanism has allowed the blackbuck to survive in small ‘refuges’ in the Great Indian Bustard Sanctuary area, a densely populated landscape with the blackbucks’ preferred grasslands interspersed with plantations and agricultural areas. A population of 250-300 animals have survived from the 1980s till today.

As the food quality declines after the monsoons, blackbucks begin to move into riskier unprotected grasslands. These seasonal changes in their movements have great significance for the blackbuck’s propensity to damage neighbouring agricultural crops. Moving to new areas increases their encounter with cropland, and the chances of them raiding crops.

Scarcity of their natural food material, grass, also motivates increased crop raiding. This study provides the first detailed clues as to why animals might be moving outside sanctuaries. A desperate search for food could thus be leading blackbucks to take more risks and get into greater conflicts with farmers.

The grasslands have been greatly utilised and modified by human settlers for a long time now and any possible undertaking of grassland conservation cannot be done without bringing the human component into consideration. The evident disparity between protecting wild animals and the development of the people that live in those areas has often been a cause for concern for advocates of either parties. Needless to say, it becomes more and more important to strike a balance between biodiversity conservation and social goals. These factors need to be given due importance as more grasslands are converted and developed for human use. It’s high time we take steps to make the coexistence of conservation and development possible.

(The author is with Gubbi Labs, a Bengaluru-based research collective)