Dragonflies are some of the fastest insects in the world and are a good asset in the garden due to their predatory habits!
What do dragonflies do in my garden?
Your garden can only benefit from having dragonflies as they are known to gobble up all sorts of garden pests such as mosquitoes, gnats and aphids. They spend most of their lives as aquatic larvae so gardens with ponds or other water sources are more likely to attract them. When the larva (or nymph) is ready to become an adult, it will climb out of the water and break out of its hard larval skin and fly away. They can be distinguished from damselflies by the fact that they cannot close their wings behind their backs and always rest with them outspread. Damselfly species are usually smaller and rarely stray from water.
How do they catch their prey?
Dragonflies have a number of adaptations which make them excellent aerial predators. Firstly, they have massive eyes with plenty of separate lenses for spotting their prey in mid air. Once the prey is spotted, their second adaptation comes into play: their separated wings. Most flying insects have linked wings but dragonflies have the unusual ability to beat each wing independently, which affords them incredible manoeuvrability in the air. They are like mini helicopters and can move upwards, downwards, forwards, backwards and side to side. In addition to these adaptations, they also have spiky legs which form a ‘basket’ to snatch their prey in mid air. Damselflies don’t quite have the speed of dragonflies and tend to catch static prey as it rests on vegetation rather than on the wing.
How do dragonflies reproduce?
During summer, you may see a very odd sight of two dragonflies flying through the air seemingly stuck together. These aren’t conjoined twins, but rather mating dragonflies in a copulation wheel. The male’s sex organs are at the front of the abdomen but the female’s are at the end of the abdomen so they must form this unique ‘wheel’ in order to mate. The male clutches onto the female’s neck with claspers at the end of its abdomen and the female curls her body round to mate. Sometimes, the male gets a bit carried away and takes to the air while still mating; sometimes even holding onto the female while she lays the eggs (talk about clingy!).
- They have stiff wings which do not fold and slim, elongated bodies
- Dragonfly and damselfly nymphs live in water and breathe through gills in their rear
- They are some of the fastest fliers in the insect world travelling at up to 15 metres per second; that’s around 34mph!
- Some countries, such as Indonesia, consider dragonflies to be a delicacy and fry them in oil before eating them. (Don’t try this at home!)