Scientists call dragonflies ‘bio-indicator species’, meaning their very presence is proof of a healthy ecosystem. But when dragonflies start disappearing, it also shows that streams and ponds are going dry or polluted with toxins.
“Dragonflies are very sensitive, most of them require an absolute pristine habitat and as soon as humans mess that up, they are gone,” explains Conniff, who has been living in Nepal for more than a decade.
Conniff co-authored the paper on the new dragonfly with noted Nepali butterfly expert Mahendra Singh Limbu, and the two often go exploring for butterflies and dragonflies on Pulchoki Hill, or in other parts of Nepal. They decided to name the new species Microgomphus phewataali after Pokhara’s Phewa Lake.
Says Limbu, “With the disappearance of every dragonfly, you know that nature is being disturbed. We humans cannot afford to disturb the ecosystem balance.”
Besides toxins, the other looming threat to insects is climate change. Europe has lost nearly 90% of its insects in the last 30 years, and in America, the population of migrating monarch butterflies has dropped by 90% in 20 years. Climate models estimate a loss of 45-99% of the suitable habitat for various species of dragonflies and damselflies by 2080 in north-eastern US. When Britain found that one-third of its dragonfly species were endangered, it opened the first ever dragonfly centre to protect what was left.
Of more than 5,000 species of dragonflies found worldwide, 140 species are found in Nepal of which a few are found nowhere else. Pulchoki on Kathmandu Valley’s southeastern rim is a hotspot for dragonflies and there has been a steady decline in butterfly and dragonfly populations there. The reason is mainly due to the pumping out of water by tankers to meet the city’s needs, the damming of the Nagmati in Shivapuri and pollution at picnic spots and riverside garbage dumps.
Rare species like the Epiophelebia, an intermediate between the dragonflies and the damselflies that used to be found only in Shivapuri National Park have probably disappeared after its stream habitat was tapped for water supply downstream.
Dragonflies begin their lifecycle as eggs and spend much of their life underwater as larvae, some for as many as seven years. Once they mature into winged adults, time is limited. Most live only up to few weeks, and since water is their primary location for eating and mating, they do not survive if ponds and springs dry up or are polluted. Dragonflies are even known to control malaria and dengue, since they feed on mosquitoes.
“In addition to cleaning up mosquitoes, dragonfly also preys on other insects that infect paddy fields, effectively increasing agricultural productivity,” explains Conniff.
Dragonflies also undertake astounding migrations: some species found in Nepal have travelled across the Himalaya from Japan and Taiwan. Others fly on, riding prevailing winds across the Indian Ocean from India to Africa. But climate change has thrown off their migratory patterns and disturbed their natural lifecycles.
Nepal has been internationally recognised for its conservation efforts. It is all set to be the first country to double its tiger population by 2022, and rhino poaching has been stopped. But while the focus is on charismatic mammals, Nepal is losing the battle to protect its valuable trove of insect species. Dragonflies are in direct peril because of the destruction of aquatic habitats.
Says Conniff: “It is important to educate people about wetland conservation and watershed management. Getting more people interested in nature and finding innovative ways to manage water is an effective approach.”
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