What Do Damselflies Eat? Mosquitoes, Gnats, and Midges
What do damselflies eat? Both nymphs and adults are strict carnivores, but the menu changes completely between the two life stages. Underwater, nymphs ambush mosquito larvae, midges, and other small invertebrates with a hinged, extendable jaw. In the air, adults snatch mosquitoes, gnats, and small flies on the wing or pluck them straight off leaves.
What Nymphs Eat Underwater
Damselfly nymphs (Zygoptera) spend most of their lives, anywhere from several months to a year, in ponds and slow streams before they ever grow wings. They are lie-in-wait predators: a nymph rests motionless on a submerged plant or on the bottom sediment and waits for something edible to swim or crawl within range. When it does, the nymph’s scoop-like extendable jaws flash outward to snatch and draw in the prey, which can be any aquatic animal small enough to fit in its mouth.
That jaw is a modified mouthpart called the labium. It normally folds flat under the head, but muscle-driven blood pressure shoots it forward in a strike that takes roughly 20 to 60 milliseconds, faster than a human eye blink. Hooked pincers on the tip close around the target and haul it back to the mandibles.
Nymphs are important predators of mosquito larvae and midges in the water, and they also take:
- Small aquatic insects, including mayfly nymphs and midge larvae
- Worms and tiny crustaceans, such as freshwater shrimp when available
- Fish fry or tadpoles, though only the largest nymphs manage this, and only occasionally
What Adults Eat in Flight
Once a nymph climbs out of the water and molts into a winged adult, its hunting method changes along with its habitat. Damselflies are weaker fliers than dragonflies, so they target smaller, softer-bodied prey: mosquitoes, gnats, midges, small flies, and occasionally moths or aphids picked off vegetation.
Their legs are held forward in a basket shape during flight, which works well for scooping mosquitoes and other small insects out of the air. Many species hunt by gleaning, picking insects directly off leaves and stems or snatching them the instant they take off, rather than chasing prey over long distances the way dragonflies do.
How Adults Hunt
Adult damselflies rely on a few repeatable tactics rather than brute speed:
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Perching: An adult lands on a low branch or blade of grass near water and waits, using its large compound eyes to spot movement before launching a short strike.
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Patrolling: Some individuals fly a fixed back-and-forth route over a patch of vegetation or open water where insects are concentrated.
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Gleaning: Rather than pursuing prey in open air, many damselflies pick insects straight off foliage, a lower-energy option suited to their lighter build.
Diet shifts somewhat across the season. Midges and mosquitoes dominate early summer meals, and later in the year adults add newly emerged damselflies and small moths as those become more abundant.
Predator and Prey at the Same Time
Damselflies sit in the middle of the food web rather than at the top of it. As predators, both nymphs and adults hold down populations of mosquitoes and midges, which matters directly for anyone living near a pond or slow-moving creek. As prey, they feed a long list of other animals: swallows and flycatchers hunt adults over open water, and fish will grab an adult that strays too close to the surface while laying eggs. Underwater, nymphs are eaten by fish, turtles, and diving birds before they ever get the chance to fly.
That two-way role, heavy predator of small insects and steady food source for larger animals, is what makes damselfly numbers a useful signal of a wetland’s health. A pond stocked with damselfly nymphs tends to have clean, oxygenated water and enough small prey to support fish and birds further up the chain.
