Aravalli Park revival in Gurugram on track, say birders
The Aravalli Biodiversity Park has, in its short life, come to be regarded as a birdwatching haven. At least 183 species have been sighted here since birders first started exploring the area, shortly after the restoration of the park started in 2010.
Birders have termed this species richness to be “extremely significant,” given that the number of species spotted makes up a large part of the total 420-odd bird species recorded across the National Capital Region.
A study by Misha Bansal, project fellow at the Centre for Ecology Development and Research (CEDAR), explains the significance and establishes, through empirical evidence, what environmentalists have reverently maintained, that efforts to revive the Aravalli Biodiversity Park are on the right track.
The sighting of endemic Indian birds in the park, such as the yellow-wattled lapwing, the rufous fronted prinia, and the Indian bushlark, show that its bioremediation (process to treat contaminated media) has brought back a large number of native species.
Earlier, the 380-acre site had been ravaged by years of indiscriminate stone mining (to cater to a booming real estate industry), resulting in poor groundwater level and soil degradation. Other plant species were unable to grow because of the influence of prososis juliflora, or ‘vilayati kikkar’, an invasive tree species rampant across the Aravallis.
The study, titled ‘Monitoring Biodiversity to Evaluate the Success of Ecological Restoration’, found that the diversity of bird species inside the park (with its restored Aravalli habitat) was significantly higher than the surrounding kikkar forests, indicating that the park has been successfully “rewilded” with an ecology of native plants and trees, which, in turn, attract birds. The park is presently home to 300 native plant species, comprising at least 101,715 mature trees, 43,284 shrubs, climbers and herbs, and at least 40 different types of grass.
“Birds are excellent indicators of how healthy the forest is, and of its growth, since they use this multitude of vegetation structures for food, shelter and breeding,” said Bansal, who headed the study as part of her master’s thesis at Jawaharlal Nehru University.
White-eared bulbuls, prinias and babblers, for instance, flock to open scrub forests, while baya weavers prefer open grasslands and Indian eagle owls perch on rocky cliff faces. The Indian paradise flycatcher, another species which has been spotted in the park, prefers denser foliage. The presence of all these species points to the various microhabitats inside the park. “Not all birds perch on trees. The park has been restored in a manner that allows these different ecosystems of native flora to flourish, and now, we see that they are facilitating a rich avian population,” said Sourajit Ghoshal, who has authored a guidebook on birds spotted in the Aravalli Biodiversity Park.
This rich diversity also indicates the presence of other species of plants and animals. If a particular bird feeds predominantly on fruit, then it would mean that there is a healthy population of fruiting trees in the park. Similarly, raptors (or birds or prey) can tell us about the presence of snakes, amphibians and insects. Bulbuls, often spotted in the park, are frugivorous, whereas the black-shouldered kite (also frequently spotted), feeds on small mammals and reptiles.
Bansal conducted her experiment over three successive winters (November to February), from 2016 to 2018. Her methodology involved conducting 167 visits — point counts — across 14 designated locations in the park (which are representative of its eight different microhabitats). During each of these visits, Bansal kept a record of the number of birds (and their species) she encountered. She then conducted the same experiment in the adjoining kikkar-dominated forests, where she carried out 60 additional point counts for good measure.
The average “encounter rate” for birds inside the park was 18, which indicate that Bansal encountered approximately 18 birds on each of her 167 visits. The encounter rate for the adjacent, unrestored forests was just 12, even with the additional 60 visits.
Bansal also recorded a total of 65 different species in the park during her study, whereas the number was 43 in the adjoining forests. Specimens observed in the park included 12 species endemic to the Indian subcontinent, two (the steppe eagle and Egyptian vulture) which are endangered and one (the Alexandrine parakeet) which is near-threatened according to the IUCN Red List.
Bansal also divided these 65 species into “foraging groups”, based on their diet. While carnivorous birds were not widely present, both frugivorous and granivorous birds were frequently spotted in the park. “Trunk gleaning insectivores, such as woodpeckers, and other birds that prefer mature vegetation (with large trees), such as the Indian grey hornbill and barbets, were not observed in the park,” Bansal explained.
However, she pointed out that barbets and hornbills were not encountered at the unrestored site either, indicating that the mature prosopis forest is not supporting native woodland birds.
“With ecological succession in the coming years, native woodpeckers, hornbills and other woodland species are expected to arrive as the vegetation matures,” Bansal said. With proper care and resources, experts say the park will grow to be a self-sustaining forest, on the lines of the nearby Mangar Bani in Faridabad, or Sariska in Rajasthan.
On the other hand, environmentalists fear that the Gurugram Metropolitan Development Authority’s plans to build a six-lane highway in close alignment to the park will obstruct its growth. “It will not only just turn away just the birds, but also the various other benefits,” said Vijay Dhasmana, who has, over the last six years, helmed the area’s restoration to its current biodiversity-rich state.
“The very nature of the land will change, resulting in an adverse ecological impact to air, water and soil, vegetation and wildlife,” he added.
In the GMDA’s vision of 9 square metres of green space per citizen in the city, the park can potentially contribute 11% of Gurugram’s green area. It is also a vital groundwater recharge zone, contributing 320 million litres of water annually. A report by the Centre for Environment Research and Education (CERE), also states that the park generates oxygen close to 7% of Delhi’s oxygen demand, while having a natural carbon dioxide sequestration capacity of 28,598 metric tonnes every 15 years.
Carbon dioxide sequestration is a process by which inorganic carbon dioxide can be stored over long periods of times, through processes such as photosynthesis, mitigating the effect of global warming. “These consequences are of national importance since they will aid in meeting the 2030 carbon stalk targets set by the Intended Nationally Determined Contributions (INDC),” Bansal said.
Given these benefits, activists, experts and even citizens believe that the park must be preserved to allow such ecological studies to continue. “Of course, it is a place for citizens to come and be in nature, but there is immense educational and scientific value here as well, and there aren’t too many places left around Delhi which offer this,” Dhasmana said. Across the NCR, he said, such habitats are fast degrading due to urbanisation.
Birders hope that as the forest canopy rises and trees bear fruit, other species will start visiting the park. The landscape is, in theory at least, suitable for other Indian species such as the grey hornbill, the Indian pitta, the Indian spotted creeper and parakeets. “Parakeets are seen in the park, but only feed there. As the trees in the park mature, there is certainly a possibility that they will start nesting in Gurugram,” said Pankaj Gupta, of the Delhi Bird Foundation.
At present, parakeet nests have been observed further north, in Delhi’s Sanjay Van and within the Jawaharlal Nehru University campus, which have a similar, but more aged, Aravalli landscape.
More recently, migratory birds have been spotted as well, such as the rufous-tailed scrub robin, which has been spotted twice since 2017. Last July, the savannah nightjar, another migrant, was photographed breeding in the park. European rollers have also been spotted in the last two years. “This indicates that the park is becoming a significant scrub patch on the Central Asian Flyway, a migratory route taken by birds from Europe and Siberia towards South Asia,” said Soma Ateesh, a city-based birder.
Surya Pradesh, of the Department of Life Sciences at JNU, said, “The study affirms the value of a place like the Aravalli Biodiversity Park. It is not surprising to see that it is supporting a more biodiverse community of birds that the surrounding areas. The place needs to be protected to allow such studies to continue.”