A major biodiversity survey across the Western Ghats has revealed a worrying decline in dragonfly and damselfly diversity, with researchers documenting only around 65% of the species historically recorded in the ecologically sensitive mountain range. Scientists warn that nearly 35% of known odonata species may now be missing from the region.
The two year study conducted between February 2021 and March 2023, covered 144 sites across five Indian States and recorded 143 odonata species, including 76 dragonflies and 67 damselflies. Among them, 40 species were found to be endemic to the Western Ghats, one of the world’s most important biodiversity hotspots.
Researchers highlighted that odonata species are extremely sensitive to environmental changes because they depend on freshwater ecosystems for breeding and survival. Their presence is often used as a biological indicator of the health of rivers, streams, ponds and wetlands. Scientists say the disappearance of several species could be an early warning sign of worsening ecological stress across the region.
The study found significant regional differences in biodiversity. Maharashtra recorded 100 species across 105 surveyed sites, including 12 endemic species. Kerala showed the highest endemic concentration, with 33 endemic species documented across 14 sites. Karnataka recorded 64 species, while Goa documented 35 species. Surveys in Gujarat recorded 18 species but no endemic species.
Several species identified during the study fall under threatened or poorly studied conservation categories on the International Union for Conservation of Nature Red List. Species such as Elattoneura souteri, Protosticta sanguinostigma, and Cyclogomphus ypsilon are currently classified as vulnerable. Researchers also noted that 22 species are listed as “data deficient,” while 16 remain “not evaluated,” indicating large gaps in scientific knowledge.
The survey additionally reported new spatial records and discoveries of lesser-known odonata taxa across the Western Ghats. Researchers documented species such as Macromidia donaldi donaldi in Pune, Merogomphus longistigma and Idionyx saffronata in Satara, and Gynacantha khasiaca in Raigad.
Scientists say the southern Western Ghats possess greater odonata diversity and endemism compared to the northern sections because of better microhabitats, dense forest cover and perennial freshwater streams, especially in regions south of Coorg and across Kerala.
The study identified several threats affecting the fragile ecosystems of the Western Ghats, including infrastructure expansion, hydropower projects, pollution, forest fires, unregulated tourism, land use changes and climate change. Researchers stressed the need for urgent conservation measures and more intensive biodiversity surveys in unexplored parts of the mountain chain.
Experts believe continued monitoring of dragonflies and damselflies could play a crucial role in assessing freshwater ecosystem health and guiding future conservation strategies in India’s biodiversity hotspots.