Observing dragonflies and damselflies in Bangladesh

I was walking along the riverbank of the Padma, scanning the water and trees for any sign of birds, when something caught my eye. The soft mud along the bank was dotted with empty husks — the exuviae of dragonfly nymphs. 

"They emerged last night," my boatman said, pointing at the delicate shells clinging to the reeds. "Usually, during the full moon, the young ones crawl out of the water and take flight."

I knelt to examine the tiny shells. Each one was a testament to transformation — from an aquatic, gill-breathing predator to the free-flying, sun-drenched hunter above. These were dragonflies and damselflies, insects we affectionately call 'foring' in Bangla. 

Their iridescent wings caught the sunlight, reflecting greens, blues, and fiery reds. They are among the most spectacular residents of Bangladesh's wetlands, marshes, ponds, ditches, and estuaries, and yet they remain underappreciated.

Dragonflies and damselflies belong to an ancient and specialised order of insects, Odonata. They were the first aerial conquerors among insects, evolving during the Carboniferous era, around 250 million years ago. 

All four wings of a dragonfly can move independently, allowing it to hover, twist sharply, and even fly backward—a master of aerial acrobatics.

Their wings — robust and versatile — exemplify a mastery of flight that even modern engineers admire. Unlike many insects, they can hover, dart, twist mid-air, and even fly backwards — an aerial skill set perfected over hundreds of millions of years.

Yet their lives are not just about dazzling flight. Dragonflies and damselflies lead dual lives, tied inseparably to water. They lay their eggs in ponds, ditches, or slow-moving rivers. The first two stages — egg and nymph — are entirely aquatic, gill-breathing and far longer than the adult stage. 

Nymphs are stealthy hunters, crawling along submerged plants and mud, ambushing mosquito larvae, midge maggots, tadpoles, and other small aquatic prey. Some even move with surprising agility along the waterbed, proving that wings are not always necessary to dominate their world.

When they finally emerge as adults, the nymph sheds its exoskeleton, leaving behind the husk I had seen along the Padma. Now a lung-breathing, terrestrial flier, the dragonfly abandons walking entirely. Its legs are no longer meant for movement on land; instead, they form a capture basket at a 45° angle, perfect for seizing prey mid-air. 

Its compound eyes swell into a dome, offering nearly 360° vision. Its four wings beat independently, allowing unparalleled manoeuvrability. Watching them dart above the water, I often marvel at how such fragile-looking creatures command the air with the precision of a flying ace.

Dragonflies are the only insects that cannot walk.

Odonates are divided into two major suborders: Zygoptera, the damselflies, and Anisoptera, the dragonflies. Damselflies are slender, delicate, and fragile, with narrow wings and subtler flight. Dragonflies are robust, powerful, and larger — masters of the skies over wetlands and rivers. Both, however, share the same life cycle and the same ecological importance.

Bangladesh, with its subtropical climate and an abundance of wetlands, ponds, marshes, and estuaries, provides an ideal home for these insects. Yet the study of Odonata — odonatology — is still emerging. Of about 5,900 species worldwide, only around 600 have been documented in the Indian subcontinent, and fewer still in Bangladesh. Each pond and ditch hides a myriad of species waiting to be noticed and recorded.

The ecological roles of dragonflies and damselflies are remarkable. As nymphs, they keep aquatic insect populations in check, feasting on mosquito larvae, midges, and gnats. Adults hunt tirelessly, catching smaller flying insects with astonishing accuracy. 

Both nymphs and adults form a crucial link in the food web, supporting birds, frogs, and other wildlife while indicating the health of freshwater habitats.

In turn, they form a vital food source for birds, frogs, and larger predators. Shorebirds, herons, storks, kingfishers, and bee-eaters rely on them as a ready meal. Wetland health, therefore, can often be gauged by the abundance and diversity of these aerial hunters. They are, quite literally, indicators of a thriving ecosystem.

As I walked along the river, my eyes followed a flash of metallic red as a dragonfly hovered just above the water. The sun was high; the air shimmered with heat and movement. Thermoregulation is crucial for these insects — they are most active under sunlight, which energises their flight muscles. From May to November, the wetlands are alive with their activity, a spectacle that combines grace and predation in equal measure.

For anyone looking to observe Odonata, patience and respect are key. They are harmless; they do not sting, bite, or release noxious substances. Their eyes, sensitive to movement and colour, respond poorly to bright clothing. 

Dull-colored outfits and quiet steps ensure that you can witness their aerial ballet without disturbance. Ponds, streams, ditches, undergrowth along riverbanks, and gardens near water are the best observation spots.

Walking back along the Padma, I glanced once more at the shimmering 'foring'. Each one was a reminder of the hidden intricacies of our wetlands — silent hunters, pest controllers, and bioindicators rolled into one. Their emergence from the water, their mastery of the air, and their place in the food web make them indispensable to our rivers, marshes, and ponds.

For the budding naturalist or casual observer, the wetlands of Bangladesh offer a treasure trove of these jewel-like creatures. 

From the first flutter of a freshly emerged nymph to the acrobatic chase of adults over sunlit water, the odonates bring both joy and insight into the health of our ecosystems. Next time you wander along a pond, riverbank, or swamp, look closely — you might just witness the dance of the river spirits.