Mandi, October 16
There is bad news for Himachal Pradesh. The dragonfly, the bio-indicators of “pure water” in rivers, ponds, lakes, wetlands and the killers of deadly mosquitoes which spread malaria and dengue fever, are being pushed to brink.
The reason: a bewildering maze of hydro-projects, roads debris, flash floods, landslides and industries in the industrial corridor of
Baddi-Barotiwala-Nalagarh belt in the state.
The dwindling density of human-friendly dragonflies, who are wrongly cursed in legends around the world as devils needles or ‘ear cutters’ predicts the frequent outbreaks of malaria and dengue among humans and pests in crops of fruits and foodgrains in the state, revealed scientists.
In a three years long study on the “faunal diversity” in Himachal Pradesh, scientists from the Zoological Survey of India (ZSI), Kolkatta have come out with some startling facts about the dragonflies in the state.
In an exclusive talk with The Tribune here after covering field-study tours in Kullu, Mandi, Kangra, Solan, Shimla and other districts in the state, Dr. R Babu, a scientist-cum-officer incharge, Miscellaneous Insect Order Section, Ministry of Environment and Forests, ZSI, said, “The dragonflies are vanishing in the project sites, industrial areas and concrete roads and towns where they once used to be in large number”.
Balu said water pollution in the Beas, Ravi, Satluj and other rivers had increased due to construction of hydropower projects, pushing the species of dragonflies to the brink. “The dragonflies are bio-indicators of pure water in the rivers, lakes and other water bodies. Its decline indicates rivers are polluted by the projects and roads or natural flash floods and landslides”, he observed.
Dr Balu said pest menace would increase around the sites, threatening crops, fruits and grains in the state in the coming years.
The three-member team of scientists have taken samples from Riwalsar and Renuka lakes and wetlands and Ravi, Satluj and Beas rivers and sites in Palampur, downstream of the 2051 MW Parbati project, 192 MW Allian-Duhangan, 105 MW Larji, 1500 MW Nathapa Jhakhri site near Rampur town, Bhakhra dam in Bilaspur town and other sites in Bharmour in Chamba, Churdhar sanctuary in Shimla-Sirmaur districts and others parts of the state to study faunal diversity in the state.
Balu said dragonflies were found in good number in lakes like Riwalsar, Bharmour and Chaurdhar areas
because there had been no considerable damage to the environment. “But the dumping of road debris and industrial pollution and natural disasters like flash floods and landslides have killed the breeding and natural habitats of dragonflies in the state”, he observed during his three years long study.
Balu said of the 500 species of dragonflies in India 70 were found in Himachal. “As many as 10 species are native and distinct to Himachal”, he noted, adding they would submit the study to the ministry of environment and forests in few months time, suggesting action to be taken to mitigate the damage done.
Scientists say female dragonflies lay eggs in or near water, often in or on floating or emergent plants. “The dragonflies spend their life in the larval form, beneath the water surface, feeding on larvae of mosquitoes, even tadpoles and fish”. As larvae of large dragonflies may live as long as five years, they can be handy in controlling the harmful insects nearby human habitations. “In the adult stage, larger species of dragonfly can live as long as four months, enough to control prying armies of mosquitoes”, the scientists added.
