Species living in bottom sediments have relatively poor eyesight, but instead use their hairs, long legs and antennae to sense prey. Others are coloured green and/or brown, which helps to provide camouflage amongst the submerged plants and algae they inhabit. The larvae of some species are covered in hairs that collect silt or organic debris from the soft sediment within which they live. Dragonfly larvae themselves can fall victim to predators, including other dragonfly larvae, fish and waterfowl. Prey includes insect larvae, crustaceans, worms, snails, leeches, tadpoles and small fish. Development takes longer in cooler waters where food is scarcer, whilst in warm waters there may be a new generation every year.ĭamselfly larvae can be separated from Dragonfly larvae by their caudal lamellae, which are fin-like structures at the end of their abdomen that act as external gills.Īll dragonfly larvae have six legs (as do adults), wing-sheaths, an extendable hinged jaw (labium) that can shoot out in an instant and catch prey. Larval development typically takes one or two years, but ranges from 2–3 months (emerald damselflies) to more than five years (Golden-ringed Dragonfly). During its time the dragonfly catches and eats live prey at every opportunity, moulting a further 5–14 times until it is fully-grown. Prolarvae that hatch below water moult almost immediately.ĭragonflies spend most of their lives in their larval stage. If the egg is laid above water, the prolarva wriggles to safety as soon as it hatches and moults within a few hours. They do this by repeatedly dipping the tips of their abdomens into water, each time releasing one or more eggs that settle below the surface.ĭuring egg-laying, male damselflies, chasers, skimmers and darters guard the females with which they have just mated, either by staying linked ‘in tandem’ or by flying in close attendance. Some female damselflies submerge completely to lay their eggs, often using their still-attached partner to pull them up again afterwards.Įggs hatch either within 2–5 weeks or, in the case of the emerald damselflies and some hawkers and darters, the following spring.Ī tiny tadpole-like prolarva emerges from the egg. Species that lay this type of egg include some emerald dragonflies as well as chasers, skimmers and darters. Emerald damselflies and Migrant Hawkers inject their eggs into rush stems well above the water surface, while other hawkers lay into rotten wood or other debris just above the waterline (see Brown Hawkers, right). The Golden-ringed Dragonfly lays its eggs by hovering vertically and stabbing its abdomen into stream-beds.Įxophytic eggs are round in shape, laid in a jelly-like substance and are deposited loosely into water. All damselflies and hawker dragonflies have scythe-like ovipositors and inject their eggs into plant stems or leaves, rotten wood or mud on or close to the surface of the water. Policies, Constitution & Annual Reportsįemale dragonflies can lay hundreds of eggs during their adult lives, in batches over a few days or even weeks.Įndophytic eggs are elongated in shape and are laid into plant material.
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