Blackbucks thrive outside a fragmented protected reserve

Once widespread across India, blackbucks are now found only in fragmented populations across the country. A key threat to the population has been the disappearance of their habitat: the savannah grasslands. While protected areas have been set up over the years, a new study that focused on blackbuck occupancy in Jayamangali Blackbuck Conservation Reserve in Karnataka’s Tumkur district found a surprising statistic — twice as many blackbucks were present outside the reserve compared to inside.

Published in the Journal for Nature Conservation, the study found that the savannah-grassland habitat inside the reserve is severely fragmented by shrubs and eucalyptus plantations, and by cropland outside it.

In 2007, 798 acres (3.1 square kilometres) in the Madhugiri taluk were notified as the Jayamangali Blackbuck Conservation Reserve (JBCR), a first in Tumkur district. K.S. Seshadri, a faculty member at Ashoka Trust for Research in Ecology and the Environment (ATREE), Bengaluru, and one of the study authors, observed more blackbucks roaming outside the reserve during his annual visits to the place.

But it wasn’t until 2023, when B.R. Manoj Kumar, then a Master’s student at ATREE (now graduated), expressed interest in exploring blackbuck occupancy in JBCR, that the study took shape. “We wanted to look into what drives blackbuck’s distribution and whether the conservation reserve is actually effective,” says Seshadri.

Blackbucks, native inhabitants of the Indian subcontinent, can be found in 13 states. Their number has declined in the past, with the most recent assessment in 2016 estimating nearly 35,000 individuals. They are listed as a species of least concern in the IUCN Red List but are protected in India under the Wildlife (Protection) Act, 1972, according to the study.

In India, some reserves have been created primarily to protect blackbucks, such as JBCR and Ranebennur Blackbuck Sanctuary in Karnataka. However, there isn’t much available information on how blackbucks use the habitat in and around these reserves, a gap that the new study addresses.

Outside the reserve

Currently, JBCR comprises habitat types such as grassland, savannah-woodland, and plantations of trees such as eucalyptus and Acacia auriculiformis, as well as invasive exotics such as Prosopis juliflora.

The study area was spread over 26.6 square kilometres, with the JBCR comprising 3.1 sq. km. and the surrounding 2-km buffer of 23.5 sq. km. The researchers classified the land use and land cover in and around the JBCR using data from Google Earth. They studied the presence of blackbuck over two seasons, in March-April 2023 and then September 2023.

Using an occupancy framework for detections, they observed that blackbucks were more likely to be found outside the reserve than inside. Blackbuck pellets were found in 74% (75 out of 102) of grids outside the reserve and in only 36 % (23 out of 65) of the grids inside in both seasons. Moreover, the researchers also directly encountered 180 blackbucks in 14 grids while doing the study, and 13 of these were outside the reserve.

“We can’t conclude that the reserve does not affect protecting the blackbucks. However, we have observed a negative association, as blackbucks are more common outside the reserve,” says Seshadri. Looking at the study’s maps, the areas with 60% to 100% detection are mostly outside the conservation reserve.

This could indicate that the habitat inside the reserve, which predominantly has shrubs and trees, might be unsuitable for them. The highest land cover inside the reserve is scrubs, which take up 48% of the reserve, followed by trees (29%). However, blackbucks are known to thrive in savannah grasslands, which make up just about 23% of the reserve area.

“Many of the trees are eucalyptus plantations, which have probably been there before the reserve was declared. Understanding the biology of blackbucks, it’s quite clear that they don’t use trees beyond seeking shelter as they are open-habitat species,” Seshadri explains.

The study also showed a high presence of clumps of Prosopis juliflora, which, Seshadri points out, blackbucks don’t eat. In fact, a 2021 study found that Prosopis juliflora negatively influenced blackbucks in Point Calimere Wildlife Sanctuary, Guindy National Park and Sathyamangalam Tiger Reserve, Tamil Nadu. The exotic species reduced grassland, grass biomass and habitat openness significantly.

Blackbucks’ occupancy and distribution are also influenced by the number of shrubs and livestock, the study states. “While the livestock affected the detections positively, we found fewer pellets in areas where there were more shrubs and trees,” Seshadri explains.

Importance of savannah grasslands

Savannah-grassland habitats, crucial for the survival of endemic animals such as the blackbuck, make up 17% of India’s landmass, but the study notes that only a small proportion of them are protected.

“The British considered the savannah grasslands as wastelands because the aristocrats didn’t get any kind of income from them. That view has persisted, and even today these grasslands are seen as regions for development projects, housing schemes, or even industrial areas instead of lands with ecological value,” says Mihir Godbole, founder of The Grasslands Trust-India, a Pune-based organisation working to conserve open natural ecosystems.

He adds that the colonisers converted vast regions of open habitats into plantations and this age-old undervaluation of savannah grasslands has led to their degradation.

“In our recent baseline survey, conducted in Maharashtra, we found that one or two flora species, which are not very high in nutrition or protein content, have a dominating presence in grasslands. Without a mix of grasses, there won’t be a healthy ecosystem that is beneficial to fauna dependent on these lands,” Godbole explains.

Excessive tree cover, especially, can significantly impact blackbucks’ survival. For instance, in April 2022, about 20 blackbuck deaths were reported in Tamil Nadu within the Raj Bhavan campus in Chennai. These deaths were linked to starvation caused by the conversion of grasslands into manicured lawns of non-native grass near the buildings and the invasion of trees.

Blackbucks are exclusively dependent on grasslands. Godbole explains that they were reintroduced in many forests of central India but didn’t survive.” Some species, like in birds, there is the lesser florican, and in herbivores, it is blackbucks, which are the key indicators that grassland species cannot do well in any other habitats,” Godbole says.

In JBCR, the study’s maps show the surrounding landscape is a fragmented patchwork of scrubs, fallow, grasslands, trees, wetlands, and agricultural fields. The lesser presence of grasslands inside the reserve could be driving the blackbucks outside it for sustenance. Godbole also links it to the better resources in the agricultural fields. “The crops yielded in agricultural fields are much more nutritious than those found in savannah grasslands. Moreover, water availability is also better in the fields.”

Actionable recommendations

In the study, the authors suggest community-based conservation could improve conservation efforts of blackbucks in JBCR. “In India, only government-owned land can be declared as conservation reserves. If we have to expand this JBCR area, one option is to develop or reassign it as a community conservation reserve, and in this case, the community manages the area,” Seshadri explains.

The other option, he suggests, is to declare the land around the conservation reserve as a protected area, like a wildlife sanctuary. “But both these options come with complications,” he adds.

The researchers also explore eco-tourism as a viable option. Seshadri points towards Wayand Wildlife Sanctuary, where villages nearby couldn’t cultivate any crops because of human-animal conflict. So, the abandoned paddy fields are treated as meadows or swamps, and local people’s houses have been converted into small homestays. “People charge a premium for others to come stay there and observe wildlife,” he says.

Godbole also finds value in eco-tourism along with agrotourism, which he thinks could lead to more responsible agricultural practices, along with the protection of community reserves. “The income generated will be sustainable and go towards the local community for the protection of wildlife,” he adds.

However, unregulated tourism and pressure on available resources could emerge as a problem. The study notes that these options require careful implementation to avoid affecting people’s rights or harming the ecosystem. “A very actionable suggestion is thinning out the tree cover inside the reserve. Removing some of the eucalyptus can help the grasslands flourish,” Seshadri says.

While reserve areas have been set up for blackbucks in India, the study in JBCR emphasises the urgent need to recognise the role of savanna grassland ecosystems, especially those outside protected areas, in biodiversity conservation.

Banner image: Blackbucks in Jayamangali Blackbuck Conservation Reserve area in Karnataka’s Tumkur district. Image by Seshadri K.S.