Delhi’s biodiversity parks are proving to be good habitats for butterflies with around 76 species of butterflies counted across the seven parks in a week-long ‘butterfly assessment week’. Last year, 71 species were counted. Of the seven biodiversity parks, the highest number of species of butterflies was spotted at the Aravalli Biodiversity Park at 68. This is higher than the 40 species counted at the park in 2017 and 54 in 2018. The Kamla Nehru Ridge has seen a similar increase in the number of species — from 38 in 2017 to 59 in 2022. The assessment week was conducted by scientists at the biodiversity parks along with volunteers, students and teachers.
A total of 5,922 butterflies were counted this year. They were found to be active after 10.30 am, when the temperature rises gradually above 24 degrees Celsius, according to scientists at the biodiversity parks. The largest populations were found to be of species like the Mottled emigrant, Common emigrant, Plain Tiger, Lemon pansy and Common grass yellow. Being sensitive towards changes, butterflies can be good indicators of the quality of habitats, according to scientists at the parks.
“When it comes to climate change, over time there is a slight range shift, where species try to leave some places. But that has not been the case with butterflies at the biodiversity parks, since a diverse habitat has been created,” said Faiyaz Khudsar, the scientist in charge of the Biodiversity Parks Programme. With the Yamuna Biodiversity Park being along the floodplain, butterflies find space among the grasses if the temperature gets high outside, giving them their own niche, Khudsar explained.
The total number of species counted at the biodiversity parks has more or less remained stable in the past few years, he said. A number of smaller butterfly species like the Indian skipper and others that tend to be found near grass were also spotted.
Pollinators like butterflies and bees are an important aspect of any ecosystem, and regenerating forests can be very difficult without pollinators, Khudsar said. The habitats created for butterflies also tend to attract bees, he added. At some of the biodiversity parks, specific habitats have been created for butterflies. At the Kamla Nehru Ridge, for instance, a butterfly conservatory has been created.
This is an enclosure of sorts where the mesh is big enough for butterflies to enter the space and leave, but the structure helps protect the host and nectar-bearing plants from monkeys, Khudsar said. Thick tree canopies that provide shade and moisture help support butterflies while open grasslands also tend to give them space, he added. The Aravalli Biodiversity Park has a similar butterfly conservatory which has a combination of host and nectar plants for butterflies. A water body is also part of butterfly conservatories to help with “mud-puddling”, a process by which the short-lived creatures draw nutrient support from the soil for growth.