Dragonflies are insect predators belonging to the order Odonata. Their life cycle includes a significant aquatic stage and a flying adult stage, each with a specialized diet and hunting strategy. This dual existence means their role as controllers of insect populations shifts dramatically depending on their developmental phase.
The Adult Dragonfly’s Menu
The adult dragonfly is an opportunistic carnivore that hunts nearly any small, soft-bodied insect it encounters in the air. Its diet consists primarily of flying pests such as gnats, midges, and mosquitoes, but it will also consume larger insects like flies, moths, and bees. They are generalized feeders, taking advantage of whatever is most abundant in their environment rather than targeting a single species.
A single adult dragonfly can consume a remarkable amount of food, sometimes eating prey equivalent to 15 to 20 percent of its own body weight daily. Larger dragonfly species may take on more substantial prey, including butterflies, wasps, and even smaller dragonflies. This continuous feeding is necessary to fuel the immense energy demands of their powerful, acrobatic flight and sustain their high-speed, predatory lifestyle.
Aerial Hunting and Feeding Mechanics
Adult dragonflies have a capture success rate that can exceed 95 percent. They do not pursue prey by chasing it down; instead, they intercept it by calculating the target’s trajectory and meeting it at a specific point in the air. Their large, multifaceted compound eyes cover most of their head, providing a nearly 360-degree field of vision and allowing them to spot prey from distances of up to 40 feet.
The primary tool for capture is a unique structure formed by their legs, often called a “flight basket.” While flying, the dragonfly extends its spiny legs forward and inward to create a net-like cage that scoops the prey out of the air. Once captured, the insect is immediately transferred to the mouthparts, often while the dragonfly is still in flight. The prey is then subdued and chewed with strong, serrated mandibles, allowing the dragonfly to consume its meal without ever needing to land.
The Voracious Nymph Diet
The dragonfly spends the majority of its life underwater as a nymph, where its diet is fundamentally different from the adult. The aquatic nymph is an effective ambush predator that lies in wait among the underwater vegetation or sediment. It will consume almost any living organism smaller than itself that moves within striking distance.
The nymph’s diet includes a range of aquatic invertebrates, such as water fleas, mosquito larvae, and aquatic worms. Larger nymphs are powerful enough to prey on small vertebrates, including tadpoles and fry (newly hatched fish). The key to the nymph’s predatory success is its highly specialized lower lip, or labium, which is hinged and folds beneath its head like a mask. When prey approaches, the labium shoots forward in a fraction of a second, grasping the victim with a pair of terminal hooks before retracting it back to the mouth.
How Dragonflies Hydrate
The primary source of hydration for an adult dragonfly comes directly from the fluids contained within the soft bodies of its insect prey. This feeding habit efficiently meets both their nutritional and hydration requirements simultaneously, significantly reducing their need to actively drink water.
Dragonflies will occasionally seek out external water sources, particularly during hot or dry weather. They are sometimes observed briefly dipping the tip of their abdomen into the water surface of a pond or puddle. This behavior is a form of active drinking, allowing them to replenish their moisture levels when the humidity is low or their internal water balance is stressed by high temperatures.