It may be small, but the fascinating ecology and biology of the dragonfly continues to hold scientists, naturalists and wildlife lovers in its thrall. With entire societies dedicated to the insect (fossils of which date its ancestors back 325 million years) and specialised wildlife travel companies providing dragonfly tours, this tiny powerhouse of nature has made a name for itself. |
Anyone who’s made the decision to take part in one of the organised dragonfly tours occurring in various parts of the world should try to learn as much about the insect as possible before leaving home. One of the most fundamental things to understand is its life cycle, which encompasses three parts.
The first stage is the egg. The female dragonfly is able to lay many hundreds in her short adult lifetime. She will generally lay batches in water (rounded exophytic eggs) or in some kind of plant material (elongated endophytic eggs); the process can take anywhere from several days and to weeks. Depending on the species, there are various methods of laying, including complete submersion in water (which requires the help of their partner to pull them out), injection into rotting wood, mud or plant stems, or hovering above the water and dipping their abdomen in repeatedly to release and deposit the eggs.
Again, depending on the species, the eggs will generally hatch within two to five weeks (although some may take far longer, waiting until spring to emerge).
When the eggs hatch, the tiny, tadpole-shaped larva that emerge moult almost immediately, or with a couple of hours. During its time as a larva, the insect begins to eat live prey and will moult many times until it is fully-grown. The larvae have six legs and the ability to breathe underwater. Their hinged jaw enables them to capture prey with ease. They tend to eat other insect larvae, tadpoles, snails, leeches and small fish.
This part of the life cycle can last anywhere from three months to up to five years and is the longest stage in the insect’s life.
Emergence and Adulthood
Unlike other winged insects like butterflies, dragonflies have no pupal stage and move directly from larva to emergence. This is achieved via one final moult, in which the insect emerges entirely from the water and sits around in the shallows, getting used to breathing air. This can take up to several days. During this time they redistribute their body fluid to push away from the larval skin and expand their wings and abdomen.
When their new form is sufficiently hardened (taking up to a couple of hours), the insect will embark on its maiden flight. In some species this may be elegant and high altitude from the outset, while for others it can be awkward and ungainly to start. They are particularly vulnerable to predators at this crucial time.
The adult takes around a week to gain its unique wing colouration and reach sexual maturity. They then return to the water in order to mate and breed, with egg laying occurring very soon after the mating. The adult stage is a very short one, with life expectancy usually only one to two weeks in the majority of species.
Dedicated Dragonfly Tours
For those with a particular fascination for this enigmatic insect, embarking on one of the organised dragonfly tours available provides the perfect opportunity to engage in sightings and gain a deeper insight into the final two stages of its life cycle.
Marissa Ellis-Snow is a freelance nature writer with a special interest in insects. Being passionate about her subject, Marissa chooses the expert-led dragonfly tours organised by Naturetrek, which have brought her unforgettable sightings of a wide range of wildlife in some of the most spectacular regions on Earth.
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