The gossamer-winged dragonfly, a beautiful and very important member of the insect world was ubiquitous once, fascinating children in particular. Now it is much less seen, causing consternation to entomologists and the green brigade. Habitat loss and climate change are cited as the key reasons endangering the species. TreeTake takes a look …
“Today I saw the dragonfly
Come from the wells where he did lie.
An inner impulse rent the veil
Of his old husk: from head to tail
Came out clear plates of sapphire mail.
He dried his wings: like gauze they grew;
Thro’ crofts and pastures wet with dew
A living flash of light he flew.”
-Alfred, Lord Tennyson
The dainty dragonfly, one of the most beautiful creatures in the insect world, has even inspired poets. But it has more to its credit than mere good looks. It is extremely fast, agile and acrobatic. Small wonder it also has cultural significance. In Japan, dragonflies are considered symbols of courage, strength and happiness. Native American tribes viewed them as representations of swiftness and activity. Their ethereal beauty and dynamic flight have inspired countless works of art, literature, and folklore.
Dragonflies belong to the order Odonata, which is divided into two suborders: Anisoptera (true dragonflies) and Zygoptera (damselflies). They are among the oldest insects, dating back to over 300 million years and predating even the dinosaurs. Fossil records reveal that prehistoric dragonflies, such as the genus Meganeura, had wingspans of up to 70 centimetres (27.5 inches), making them some of the largest insects ever to have existed, as well as amongst the earliest winged insects to evolve. Modern dragonflies, although smaller, still exhibit remarkable evolutionary adaptability, as well as very proficient predatory skills, which have allowed them to thrive for millions of years.
There are over 5,000 known species of dragonflies, each exhibiting unique colours, patterns, and behaviours. They can be found in almost every part of the world, from tropical rainforests to temperate regions.
Sadly, dragonflies are on the decline globally, with 16% of the species threatened with extinction, primarily due to the destruction and deterioration of their wetland habitats on account of human activities like agriculture and urban development. Other key threats include water pollution from pesticides, climate change-induced droughts and the introduction of invasive species. Their decline serves as a critical warning sign for the health of freshwater ecosystems, as dragonflies are sensitive indicators of environmental quality. Degradation due to urbanisation, agriculture, dam construction and pollution destroys their aquatic breeding grounds. Shifting weather patterns and climate change also hurt wetland ecosystems.
Dr Geetanjali Mishra, an entomologist, Department of Zoology, Lucknow University, said: “Not just dragonflies but the population of all insects is declining dramatically. A recent research has shown that almost 70 to 80 per cent of insect populations have declined worldwide. As for dragonflies, they reproduce and then they do their egg-laying in water bodies, mostly stagnant water. And their development is quite long. It takes a long time for them to grow from their egg to an adult. So, if you're looking at the water bodies around us, overall, they're decreasing. It's not like if it rains and a small puddle is formed, a dragonfly will lay eggs and grow in it. It's not like that. The egg-to-adult life cycle can take about two to three months. So, if you don't have very viable water bodies, then obviously the necessary conditions for their reproduction and growth are lacking. This is a very major reason, and in general, insect populations are declining at a rapid pace because no one is paying attention to them. We focus on larger animals, while insects, with their highest numbers and highest diversity, are the most important part of our food web. And if insect populations continue to decline at this rate, our food web will collapse because they provide food for so many animals. They are pollinators, decomposers and recyclers. And the decline of dragonflies is a major factor. Dragonflies are natural mosquito control agents. So mosquitoes will definitely increase. When their natural predators are decreasing in their system, they will increase.”
“Overall, conservation of water bodies is very important. The most important thing is that if you focus specifically on dragonflies, then conserving small pond systems, conserving water bodies, and conserving wetlands is essential. It is not enough just to declare a Ramsar site. Conservation of local water bodies, the small ponds near homes that were once small and are now gradually being encroached upon, is crucial. We declare wetlands, and they are conserved. But that's not enough for our vast land area, not enough for our population. Conservation of small local water bodies, which are disappearing at such a rapid pace, is crucial. Damselflies are very good pollinators. The ecosystem services of insects would make a whole story because they are pollinators, biocontrol agents, weed controllers and have many roles. But dragonflies are largely recognised as more effective pollinators and predators. Our water bodies in houses aren't usually large. We used to have small water bodies in our schools too. That's all gone now. I think if we conserve local water bodies, it will make a big difference.”
Why are dragonflies threatened?
Dr Satya Prakash of Rajmata Vijayaraje Scindia Krishi Vishwa Vidyalaya (RVSKVV), Gwalior, said: “Dragonflies are declining worldwide mainly because their natural habitats — wetlands, ponds and rivers — are being destroyed or polluted. Rapid urbanisation, industrial waste, the use of pesticides and climate change have caused serious damage to freshwater ecosystems where dragonflies breed and feed. Pollution reduces water quality, while pesticides kill both dragonfly larvae and the insects they eat. In addition, the drainage of marshes and conversion of wetlands into farmland or construction areas remove their breeding grounds.”
He added that dragonfly nymphs are aquatic and can be found in streams, rivers, ponds, lakes, and wetlands. They live in areas where water is slow-moving or still. They are likely to be found under rocks and wood. Urban development, unsustainable agriculture and other land-use changes destroy the wetlands. The rapid expansion of cities alters and destroys natural habitats essential for dragonflies to breed and live. Paved surfaces and buildings replace the ponds, rivers, and grasslands that are critical to their life cycle.
Pollution can alter the dissolved oxygen levels in water, which is critical for the survival of dragonfly larvae, forcing them to move or causing local extinction. Dragonflies spend a significant part of their lives as larvae in water. Increased pollution in rivers, ponds and lakes directly impacts their survival. Because they are so sensitive to water quality, dragonflies are considered "bio-indicators" for the health of a wetland. Both the larvae and adults are highly sensitive to their residual habitat characteristics. Thus, the presence or absence of certain species in a given area indicates the nature of that habitat as well as its quality.
Building dams alters water flow and creates stagnant water, destroying the habitat for species that require free-flowing streams for breeding. Changes in rainfall patterns can dramatically impact wetland ecosystems, affecting the availability of suitable breeding habitats. Erratic rainfall can also disrupt their breeding cycles. Droughts can reduce the availability of the temporary pools where many species breed. Invasive species in wetlands and water bodies can also threaten the survival of dragonfly larvae. Dragonflies are found near clean, healthy freshwater habitats such as ponds, streams, lakes, and other wetlands.
According to a recent study, 8 dragonfly species have gone locally extinct in Pune district, underlining the impact of urbanisation and other factors on local dragonfly populations. Experts have cited reasons such as land-use changes, increased water pollution, changing weather patterns, and rapid Few know that there is urbanisation for this local extinction. Few know that there are certain species, such as the Globe Skimmer (Pantala flavescens), that migrate. Globe Skimmer migrates across the Indian Ocean from India to Africa, chasing the monsoon rains to find temporary pools for breeding. This seasonal movement might make their local numbers appear reduced at certain times of the year. So, according to recent research, dragonflies in India are disappearing in certain areas due to human-induced environmental changes.
Fewer dragonflies indicate environmental changes are impacting their necessary wetland habitats. Hence, according to the International Union for Conservation of Nature (IUCN), protecting vital ecosystems is crucial for their survival and for the health of the environment. Naturalist Dheerendra Singh, author of Field Guide to the Dragonflies and Damselflies of North West India, said: “There's only one reason for this natural decline: the habitat is being destroyed. And when there's habitat loss, then there will obviously be decline. Generally, a wetland is a habitat. If a wetland dries up, or there's construction, or the resources are completely depleted, then many other dragonfly species will begin to decline. So, the main reason is habitat loss, if species are declining there. So, how do we know if dragonflies are declining there? You can find out where it is, how it is and what species are there. If you do a particular long-term study, you'll know for at least a year which species have come this year and which ones haven't come next year.”
“Dragonflies' life cycle is related to water. When the water level decreases or disappears from an area, dragonflies will migrate locally or expand. It depends on the species. Many species are such that, if the habitat declines or disappears, they can survive by moving to another place. Others won't go anywhere else, even if it costs them their lives. Dragonflies play a very important role in the ecosystem. They act as bio-indicators, control mosquitoes, human stinging bugs and other flies, and many other things, especially mosquitoes, because their larvae and mosquito larvae live in water. So, they are carnivorous; their larvae control water, and even after they become adults and dragonflies, they feed mostly on mosquitoes, even in houses. If water bodies are created for them, i.e. man-made water bodies, then the population can increase. I have had a water body at my place for 10 months. I created a small pond at home. I made a plastic bottom for it and then filled it with soil and different types of aquatic plants. Dragonflies started coming there on their own, without being invited. So, we have a dragonfly habitat here. Water conservation is essential, and if the habitat is protected, dragonfly species will start coming in, and the surviving population will increase.”
Why are dragonflies important in the ecosystem?
Dr Satya Prakash said: “Dragonflies play a vital role in the food chain. They are predators of mosquitoes, flies, and other small insects, helping control pest populations naturally. Their larvae also serve as food for fish, frogs and birds. Thus, losing dragonflies can disturb the ecological balance of both aquatic and terrestrial systems.” Dragonflies are sensitive to environmental changes, so their presence or absence can indicate the health of a local ecosystem. In their aerial form, dragonflies are highly effective hunters known for their rapid flight and 360° vision, which allows them to snatch prey mid-air. They specifically target and consume numerous flying insects, including mosquitoes, flies, horseflies, midges and other flying insects and even smaller dragonflies. Their predatory behaviour makes them valuable natural allies in agriculture and public health for managing pest insects without the use of pesticides.
The larval stage is also a voracious carnivore, hunting in freshwater environments and eating other aquatic invertebrates and small vertebrates. By consuming large numbers of mosquitoes and flies, dragonflies play a crucial role in regulating these populations and reducing the transmission of diseases they carry. Despite their hunting prowess, adult and nymph dragonflies are themselves an important food source for various animals higher up the food chain, like fish, frogs and turtles, etc.
Ray of hope
However, a new survey across seven DDA biodiversity parks in Delhi has disclosed a rise in the overall count of dragonflies and damselflies and a new species. There has been a 54% increase from 8,630 last year to 13,253 so far this year. The survey, which was undertaken between September 25 and 27, said park-wise tally of species also rose at a few sites, including Neela Hauz, Aravalli and Kalindi. For the first time, Yellow-tailed Ashy Skimmer (Potamarcha congener) was also recorded at the Yamuna Biodiversity Park. Dr Faiyaz Khudsar, scientist-in-charge of Yamuna Biodiversity Park, said this species, which was found across the northern and northwestern plains, was seen here for the first time. So, one can say that all is not lost, as researchers continue to discover new species in India's biodiversity hotspots, such as the Western Ghats. A recent study in Pune that reported local extinctions also documented 27 new species for the district. Population surges were also seen in protected areas.
What should be done?
Decisions on monitoring and evaluation during the early stages of conservation programmes are critical to ensure that populations, habitats and ecosystems are effectively and efficiently assessed over time to measure the level of conservation success. Ponds, wetlands and other water bodies should be created and maintained to provide suitable habitats for dragonfly nymphs. Native plants should be planted around water bodies to provide suitable resting spots and breeding sites for adult dragonflies.
To conserve dragonfly populations, healthy dragonfly habitats should be created by adding a pond with native aquatic and marginal plants in gardens, ensuring shallow edges and a deep section for overwintering, and avoiding fish in the pond, as they prey on dragonfly nymphs. A pond is the best way to provide essential habitat for breeding and development. Even a small pond or container pond is beneficial. An undulating shape with a deep section (at least 60cm) and shallow edges provides natural features. Rocks, stones, logs and moss can be added around the edges for basking, egg-laying, and easy exits. It should be placed in a sunny spot, sheltered from the wind. Rainwater should be used to fill the pond; if using tap water, one should let it sit for a few days for the chlorine to dissipate.
One can support dragonfly conservation by planting native wildflowers to provide prey and perching sites for adults, reducing lawn mowing, avoiding pesticides and joining or supporting local conservation efforts. Submerged plants like hornwort provide shelter and oxygen for larvae. Water lilies and frogbit provide perching and egg-laying spots. Water crowfoot and reeds give emergent and roosting areas. Native wildflowers in a garden support a food source for adult dragonflies. There should be no fish, as they prey on dragonfly nymphs and add excess nutrients. Invasive plants should be removed from the pond and garden to prevent them from outcompeting native species. Lawns should be mowed less often to encourage native wildflowers that serve as prey and habitat for dragonflies. Pesticides, which harm dragonflies and other beneficial insects, should be avoided and conservation efforts should be backed.
In this context, one can support local organisations or initiatives that restore wetlands and natural habitats. One can also engage in citizen science projects to help identify and monitor dragonflies, contributing to scientific understanding and conservation efforts. Public awareness about the importance of dragonflies and their habitats should be promoted through various media platforms.
Dr Satya Prakash said: “Governments and communities should conserve ponds, lakes, and marshes where dragonflies breed. Proper waste management and limiting the use of harmful pesticides and fertilisers will help keep water bodies clean. Planting native aquatic plants and maintaining small, clean ponds can provide safe breeding grounds. Educating people about the ecological importance of dragonflies can encourage conservation efforts. Regular surveys can help identify declining species and take timely action. The decline of dragonflies is a warning sign of the poor health of our freshwater ecosystems. By protecting their habitats and reducing pollution, we can help restore their populations and maintain the natural balance of the environment.”
DID YOU KNOW?
The dragonflies of the prehistoric era were enormous, some having a wingspan of 30 inches! The insect is small. So why the name dragonfly? In Romanian folklore, the Devil turned St. George's horse into a huge insect. So, it was known as "Devil's Horse". The Romanian word drac means both "Devil" and "dragon", so the insect soon became "dragonfly". Dragonflies do not have teeth, though they belong to the order Odonata, which means “toothed”. But they have sharp mandibles for tearing and eating prey. Their bite is not dangerous, but can definitely pinch! Some dragonflies can fly at a speed of 35 miles per hour and can also eat while flying!
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