Dragonflies are ancient insects, having navigated the skies for hundreds of millions of years. With their remarkable flight and keen senses, they are formidable predators within the insect world.
Dragonfly’s Mosquito Diet
Adult dragonflies are opportunistic predators, with mosquitoes forming a notable portion of their diet. A single adult can consume 30 to over 100 mosquitoes daily. However, studies show mosquitoes are not always a primary food source, as their diet depends on readily available flying insects. Consumption rates vary based on mosquito abundance, dragonfly species, and environmental conditions. Dragonflies also prey on midges, gnats, flies, bees, butterflies, and even smaller dragonflies.
Hunting Strategies
Dragonflies are highly adapted aerial hunters, employing sophisticated strategies to capture their prey mid-flight. Their exceptional eyesight is a key adaptation, with large compound eyes that can contain up to 30,000 individual facets, providing nearly 360-degree vision. About 80% of a dragonfly’s brain is dedicated to visual processing, allowing them to detect and track prey effectively. They can process visual information much faster than humans, enabling them to perceive the world in what appears to be slow motion, giving them ample time to react to their targets.
Their flight capabilities are equally impressive, enabling them to hover, fly backward, and achieve speeds of up to 30 miles per hour. This agility allows them to intercept prey with high precision. Dragonflies often catch insects by forming a basket with their spiny legs, scooping up their meal without needing to land. They also employ predictive hunting, anticipating the trajectory of their prey rather than merely reacting to its movements, leading to a high hunting success rate, sometimes as high as 95%.
Larval Stage: Aquatic Mosquito Eaters
The predatory role of dragonflies begins long before they take to the skies, during their larval or nymph stage. Dragonfly nymphs are aquatic predators that reside in ponds, lakes, and other water bodies, spending the majority of their lives—sometimes up to several years—underwater. These nymphs are voracious eaters, preying on mosquito larvae and pupae, along with other small aquatic invertebrates, and even small fish or tadpoles.
The nymphs possess a unique and specialized mouthpart called a labium, often referred to as a “mask.” This extendable jaw is folded under their head when at rest, but can rapidly shoot out to snatch unsuspecting prey. The labium extends and retracts quickly, typically within milliseconds, pulling the captured prey back to their mandibles for consumption. A single dragonfly nymph can consume an average of 40 mosquito larvae per day, significantly contributing to the reduction of mosquito populations in aquatic environments. Their effectiveness in controlling mosquito larvae suggests that this developmental stage plays a substantial part in natural mosquito control efforts.