But did you know that the flying insects we see are the descendants of insects that pre-date the dinosaurs? Today’s dragonflies are large, certainly compared to other insects, but they would hardly make a snack for their 300 million year old ancestors, some of which boasted 1m wing-spans!
In the UK and in English, the word “dragonfly” covers two different groups of insects: damselflies (or zygoptera – from Greek meaning “similar wings”, because the two pairs of wings the adults have are identical), and dragonflies (or anisoptera – “different wings”, as the front pair is usually thinner and longer than the rear pair). Both groups are classified as Odonata – literally “toothed jaws”.
Around the world there are approximately 5,300 species of odonata; most live in the tropics, but in the UK there are about 40 regularly breeding species.
The impressive dragonflies we see buzzing around are the short-lived, adult forms of larvae that have lived for (usually several) years, out of sight in a lake, pond or moving water course, eating their way through aquatic invertebrates in order to grow and lay down reserves that enable them to undergo the transformation from “ugly” to “dazzling”.
Larvae are found in all water habitats – delicate blue-tailed damselflies can use tiny, temporary pools or puddles for laying their eggs in, the brilliant emerald dragonfly prefers large pools or lakes on heaths, whereas the club-tailed dragonfly will only use the broad, languid River Thames.
Whilst the larvae are restricted to water the adults can be found anywhere, woods, meadows, gardens; anywhere that small flying insects can be snatched. But they are most commonly encountered near water, where breeding takes place.
Our damselflies tend to be smaller, more delicate creatures, with less dramatic colouration (usually blue, red or black). However, the beautiful and the banded demoiselles are stunning damselflies with shimmering, metallic colours.
Damselflies may also be distinguished by their habit of holding their wings together in line with their abdomens when at rest, instead of at right angles to the body as dragonflies do; although beware as emerald damselflies go for a 450 halfway position, but this can help to identify them quickly before they take flight at your approach.
BBOWT nature reserves with wetland habitats, such as Weston Turville Reservoir and Calvert Jubilee, can be good places for dragonfly spotting. But wetland habitats and their wildlife, including dragonflies and damselflies, are under threat around the world; mostly the threat comes from the quality of the water feeding them. BBOWT is working with the Environment Agency and Natural England to maintain clean water supplies to our reserves to safeguard the precious wetland wildlife.
Keep out for dragons and damsels when you’re out near water this summer. Most are fast so patience, binoculars and a good field guide are essential if you want to be able to identify individuals. Alternatively, just marvel at their grace, agility and energy, and thank them for the share of midges, mosquitoes and flies that they take to make our summer waterside walks more enjoyable.