Dragonflies, damselflies numbers surge in Delhi biodiversity parks; new species spotted at Yamuna
Scientists documented a total of 13,253 dragonflies and damselflies during the three-day census from September 25 to 27, up from 8,630 sightings in 2024.
A recent survey of dragonflies and damselflies across seven biodiversity parks in Delhi has recorded a rise of around 4,500 individuals compared with last year, though overall species diversity has remained largely unchanged. The survey also spotted a new species this year, the yellow-tailed ashy skimmer, in Yamuna Biodiversity Park.
Scientists documented a total of 13,253 dragonflies and damselflies during the three-day census from September 25 to 27, up from 8,630 sightings in 2024.
The survey covered seven Delhi Development Authority (DDA) biodiversity parks of Yamuna, Aravalli, Neela Hauz, Tilpath Valley, Kamla Nehru Ridge, Tughlaqabad, and Kalindi. Students from Delhi University colleges also participated in the census.
Faiyaz Khudsar, scientist in charge of the DDA biodiversity programme, said dragonflies and damselflies are ideal indicators of urban biodiversity, as their presence reflects water quality in breeding sites and the condition of surrounding vegetation. “These invertebrates respond strongly to environmental conditions and are valuable for evaluating biodiversity loss due to land-use intensification in cities,” he added.
Asked about the surge in numbers this year, Khudsar attributed it to continuous heavy rains, which created numerous temporary water bodies that expanded breeding habitats. “This increase is also visible in mosquito populations, which have declined, as dragonflies and damselflies are natural biological controls for mosquitoes,” he noted.
Meanwhile, the number of species rose from 94 to 118 this year.
{{/usCountry}}Meanwhile, the number of species rose from 94 to 118 this year.
{{/usCountry}}The Kamla Nehru Ridge recorded 3,935 individuals from 26 species this year, whereas, a total of 3,150 individuals were recorded across 25 species last year and only 150 individuals in 2023.
{{/usCountry}}The Kamla Nehru Ridge recorded 3,935 individuals from 26 species this year, whereas, a total of 3,150 individuals were recorded across 25 species last year and only 150 individuals in 2023.
{{/usCountry}}In the Aravalli biodiversity park, a total of 2,249 individuals were observed across 16 species, a marked increase from last year’s 503 individuals across 10 species.
{{/usCountry}}In the Aravalli biodiversity park, a total of 2,249 individuals were observed across 16 species, a marked increase from last year’s 503 individuals across 10 species.
{{/usCountry}}In Yamuna biodiversity park, where 1,730 sightings were made, a new species was observed this year. “Yellow-tailed ashy kimmer (potamarcha congener) is a new addition to the park and probably to Delhi too,” Khudsar added.
{{/usCountry}}In Yamuna biodiversity park, where 1,730 sightings were made, a new species was observed this year. “Yellow-tailed ashy kimmer (potamarcha congener) is a new addition to the park and probably to Delhi too,” Khudsar added.
{{/usCountry}}Some of the most observed species in the Yamuna biodiversity park include rudy marsh skimmer and the golden dartlet.
{{/usCountry}}Some of the most observed species in the Yamuna biodiversity park include rudy marsh skimmer and the golden dartlet.
{{/usCountry}}The Kalindi biodiversity park also saw a spike in numbers, from 2,840 last year to 3,682 this year. The number of species at Kalindi now stands at 20, as compared to 14 last year.
Some of the most seen species across the seven biodiversity parks include the wandering glider, observed in Aravalli biodiversity park, Kamla Nehru Ridge, Tilpath Valley biodiversity and Kalindi biodiversity park. Meanwhile, the ditch jewel was seen extensively in Tughlaqabad biodiversity park and the Neela Hauz biodiversity park.
These insects form a part of the “odonata” family. Odonatas are characterised by large round heads, compound eyes, two pairs of long, transparent wings and elongated abdomens.
The dragonfly count was first done in 2018 across three biodiversity parks. It has been conducted annually for the past four years now since 2022.
