The ‘mad babul’ in the grasslands of Banni threatens the habitat of the Indian desert fox
- Prosopis juliflora, a salt-tolerant and fruit-bearing tree, thrived in the grasslands of Banni in Gujarat.
- The encroachment of this invasive woody plant, however, results in a loss of habitat and resources for the desert fox.
- Local communities and government agencies are aware of its impact, but the lack of an inclusive plan hampers decision-making when it comes to dealing with it.
The Banni grasslands of Gujarat are home to 40 species of grasses – from a rare grass that has no local name to one that grows almost only inside pit walls. The grasses, in turn, are home to a variety of wildlife, from the endemic spiny-tailed lizard to the migratory birds that travel here after the monsoon turns the dry expanses into lush wetlands. But an invasive woody plant, Prosopis juliflora, encroaches on a large part of the prairies. This in turn leads to the loss of habitat and resources for the Indian desert fox, an open habitat species. This could potentially impact the conservation status of this already restricted species in India.
Banni, once one of the largest tropical grasslands in Asia, is located on the northern border of Kutch district in Gujarat. It is part of the hot semi-arid region of India, with an average annual rainfall of around 300mm. The vegetation here is generally dominated by grass with salt-tolerant vegetation in areas of high salinity.
In the 1950s, the construction of dams on the rivers that flowed into Banni caused a sudden surge of salinity incursion. Local authorities have identified it as a source of concern. To stop it, the state government started introducing a tree from South America, known as Prosopis juliflorato the area in the 1960s. “The salt-tolerant, fruit-bearing tree has thrived in the area ever since. We call it gando baval or ‘mad babul’ now, since it now grows everywhere,” says Madhav, a local resident who has worked with researchers in the area to document the spread of the particular species.
Ecologically, Prosopis juliflora is a resilient species and can withstand extremely harsh weather and soil conditions. Its extensive root system allows it to easily draw groundwater, so it stays green even in the height of summer. “This is exactly the reason why the species has been systematically planted in different dry landscapes of India – to ‘green’ the deserts and provide livelihoods and firewood for the inhabitants of these regions,” explains Chetan Misher, a researcher at the Ashoka Trust for Research in Ecology and the Environment, who co-published a paper in 2021 on Indian desert fox occupancy and diet in a Prosopis juliflora– overgrown semi-arid grasslands.
Naturally dry landscapes also exhibit less complex plant communities, thus posing less resistance to any newly introduced species. So the Prosopis juliflora spread rapidly in the region. Indeed, since the introduction of the invasive species in the 1960s, more than 50% of the grasslands of Banni have transformed into a stable landscape dominated by woody vegetation.
The rapid expansion of woody species, however, is reducing suitable habitat for the desert fox, negatively affecting its population. “The desert fox (which is a specialist in open dry grasslands and deserts) avoids overgrown habitat with Prosopis and uses native saline brush more often,” says Misher.
The Indian desert fox (Vulpes vulpes pusillalisten)) is one of three red fox subspecies found in India. The other two subspecies are the Kashmir fox and the Tibetan red fox. Little is published about the Indian desert fox, but what those who study it know is that its habitat includes dunes, saline scrub grasslands, and semi-arid scrub savannahs. It shelters in burrows dug in the ground near the vegetation cover of reeds and shrubs. Gerbils, other rodents and spiny-tailed lizards are its main prey.
This subspecies has been given the highest legal protection in India (Appendix I) under the Indian Wildlife Protection Act 1972. But despite its legal status, it is poached for its fur and meat. Rapid urbanization, industrialization and the introduction of invasive plant species, such as Prosopis juliflora in their habitats have also impacted the number of desert foxes. “Like any other species in the desert landscape, the Indian desert fox is also commonly found in human-dominated areas and there is currently no particular conservation plan for the species in place. But Prosopis encroachment tends to provide favorable habitat for some generalist species such as the jackal, which in turn increases the risk of intra-guild competition and predation for the desert fox, further affecting its population and distribution,” explains Misher.
While local people and government agencies are aware of the impact of invasive species such as Prosopis juliflorathe problem is the lack of an inclusive plan and the involvement of locals and other stakeholders in decision-making when it comes to dealing with invasive species.
“Complete removal of Prosopis followed by regular removal of new seedlings for a few years is the most effective way to restore native habitats that have been impacted by the Prosopis invasion. But restoration is multidisciplinary and other aspects of Prosopis should be considered before action is taken, such as the dependence of the inhabitants’ livelihoods on the Prosopis“, explains Misher. Their recent study also showed that the mechanical removal of Prosopis leads to three times higher species richness and six times higher ground cover of herbaceous plants.
Plus, it’s not just about the desert fox. Most desert species are ignored, the researchers note. Little is known about them or the impact invasive species have on them. “Our study revealed that the native habitats of the Banni landscape harbor the unique species adapted to arid lands such as pygmy gerbils and desert gerbils, and these species were completely absent from any Prosopis invaded habitat showing their susceptibility to bush encroachment. So yes, long-term ecological monitoring is necessary for the management of invasive species and wildlife populations,” says Misher.
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Banner image: Desert fox in a den. Photo by Sumeet Moghe/Wikimedia Commons.