Dragonflies are ancient insects found in diverse habitats. They are skilled hunters, and their predatory nature makes them significant components of the ecosystems they inhabit.
Larval Stage Diet
Dragonfly nymphs, also known as larvae, are aquatic predators with a voracious appetite. They spend most of their lives underwater, feeding on smaller aquatic organisms. Their diet includes mosquito larvae, aquatic insects, worms, small crustaceans, tadpoles, and small fish. Larger nymphs can tackle substantial prey, such as sticklebacks.
These nymphs employ an ambush hunting strategy, lying in wait on aquatic vegetation or camouflaged against the substrate. When prey comes within reach, the nymph rapidly extends a specialized lower lip, called a labium or mask. This hinged mouthpart shoots forward with speed, grasping the prey with terminal hooks or palpi before retracting it back to the nymph’s mandibles for consumption. The entire extension and retraction can occur in as little as 15-40 milliseconds.
Adult Stage Diet
Adult dragonflies are aerial predators, primarily consuming other flying insects. Their diet mainly consists of mosquitoes, flies, gnats, midges, moths, and smaller butterflies. They are opportunistic hunters and will capture almost any insect they can overpower, including other dragonflies and damselflies.
Adult dragonflies are efficient hunters, catching a high percentage of the prey they pursue. They control populations of various insects, including those considered pests. A dragonfly can consume a fifth of its body weight in a single day.
Hunting Techniques
Dragonflies employ techniques to capture their prey. Adult dragonflies possess flight capabilities, allowing them to hover, fly backward, and change direction rapidly for aerial hunting. Their large, multifaceted compound eyes, containing nearly 24,000 individual optical units, provide a wide field of view, enabling them to detect and track prey. A specialized high-resolution zone in their eyes helps them focus on targets flying above against the sky.
When an adult dragonfly spots prey, it calculates an interception trajectory, predicting where the prey will be rather than chasing it. They use their spiny legs to form a “basket” or net, scooping prey directly out of the air while in flight. Once captured, larger prey items may be bitten on the head and carried to a perch, where the wings are discarded before consumption. For nymphs, the extendable labium, with its complex grasping mechanism and sensory organs, remains their primary hunting tool. This “mask” is propelled by a rapid release of stored energy, like a spring-loaded catapult system, allowing for a swift and precise strike even in water.