Dragonflies are the raptors of the insect world. To us humans, these brightly coloured creatures are an integral part of summer.
Dragonflies are instantly recognisable by their long, thin bodies and four veiny wings.
Dragonfly facts
Scientific name: Anisoptera
Family: Zygoptera
Diet: Other insects, like flies, midges, and mosquitoes
Predators: Birds (in particular, hobbies), spiders, frogs, and larger dragonflies
Size: 3-8.5cm with a maximum 12cm wingspan
Lifespan: Typically, a few months in their adult form
About dragonflies
To other insects, and even small fish, the dragonfly is a voracious hunter from hatching as aquatic larvae to its peak as a flying adult. Dragonflies are one of the fastest insects in the UK, reaching speeds of nearly 30 miles per hour. These agile acrobats of the air can use each of their four wings independently to fly forwards, backwards, sideways, and hover.
This behaviour is understandable when you consider that the dragonfly's predecessors stalked the planet almost 300 million years ago, pre-dating birds by some 150 million years. One of the first insects to evolve on Earth, dragonflies had wingspans nearly a metre long and were five times larger than the average insect alive today.
Dragonflies are still widespread throughout the UK, especially in the southern counties.
Dragonflies and our canals
Many dragonflies are water-lovers, particularly during the breeding season, when they stay close to canals, rivers, and ponds. You'll also see them in woods, fields, and gardens.
The reed fringes of many of our canals and rivers provide excellent breeding sites and hunting grounds for dragonflies. Our maintenance programme involves creating and improving canal banks with dragonflies in mind.
We build soft banks using coir roles or hazel faggots to encourage reed fringes to grow. These create ideal habitats for many insects, particularly dragonflies.
With long bodies and two narrow pairs of veiny wings, dragonflies are distinctive among insects. Dragonflies have a powerful build and bulging eyes that cover most of their head and provide a near-360-degree field of vision for some species.
Here are the dragonfly species you'll most likely see by our canals.
A common darter dragonfly, brown in colour with veiny wings, rests on a stone. Photo by Jack Perks.
Emperor dragonfly
One of the largest species in the UK, the emperor dragonfly measures 7.8cm long. Males are pale blue with a green thorax and black stripe along the body. Females are a slightly duller blue. Both have green-blue eyes and are recognised by their impressive size.
Emperor dragonflies are widespread in England and Wales, often found by canals from May to October. They're rarely far from water.
Common darter dragonfly
As the name suggests, common darter dragonflies are widespread throughout the UK. Males are orange-red, and females are yellow. Both sexes have a brown thorax. You'll see common darters from May to September – and a few may even still be in flight as late as November.
Ruddy darter dragonfly
Ruddy darter dragonflies are widespread and rarely found too far from water. Males are blood-red with black legs and slightly shorter than the common darter. Females are yellow with black legs and a 'T' mark on the thorax.
Ruddy darter dragonflies are often seen from June to October, but their main flight period is in July and August.
Four-spotted chaser dragonfly
Four-spotted chaser dragonflies are mostly brown, with a black tip to the tail and yellow sides. They have two black spots on each wing.
These dragonflies are found throughout the UK from May to September, preferring still water.
Migrant hawker dragonfly
Migrant hawker dragonflies have a short body and are brown with yellow stripes. They have a distinctive upward-pointing abdomen. Males have blue spots, while females have yellow ones. Both sexes are identifiable by their yellow 'T' marking on the abdomen.
Migrant hawkers migrate each summer, often seen by water from July to November.
Common hawker dragonfly
Common hawker dragonflies are dark with small spots and yellow veins on the wing. Males are mostly black with blue spots, while females are brown with yellow or green spots.
These dragonflies are found in the north and west and are absent from the east of England. Common hawkers are on the wing from late June to October.
Dragonflies are aggressive predators and agile fliers. They're among the fastest insects but their wings must be warm to fly. They will make a wing-whirring motion and perch in the sun to generate heat. Their eyes have thousands of lenses that enable them to see up to 12 metres away with panoramic vision.
They eat other insects, including flies, midges, mosquitoes, and even butterflies and smaller dragonflies. They catch their prey in flight using their long legs. Some species eat their prey in the air, while most carry it to a perch to eat.
Unlike butterflies, dragonflies don't feed on nectar and aren't attracted to plants.
How do dragonflies breed?
Dragonflies have a unique mating posture, similar to damselflies, in which they form a wheel position in the air. Males grip the female's head with their legs to form a circle. Some remain in tandem while the female lays her eggs.
Young dragonflies, called larvae, nymphs, or naiads, are aquatic predators – just as ferocious below water as the adults are above. Wingless and dull in colour, larvae often blend into the surrounding sediment or water plants. They might live as larvae for up to five years before emerging from the water.
Adults usually only survive in dragonfly form for just a few months. They're often eaten by birds or die of cold in the autumn and winter.
A female dragonfly lays her eggs in or near water. Males may guard her while she lays her eggs.
Where do dragonflies live?
Dragonflies love to live near water – whether that's a canal, river, stream, reservoir, or pond – and hunt along hedgerows and woodlands. They typically make their homes and prey on food in well-vegetated waterway banks.
There are 36 dragonfly species in the UK. In the summer months, it's easy to see the glittering wings of a dragonfly flitting across the canal.
With climate change warming temperatures, many species are expanding their range further north – like emperors, black-tailed skimmers, and ruddy darters.
What's the best time of day to spot dragonflies?
Dragonflies are cold-blooded, so the best time of day to see them is noon to early afternoon. They are most active during the sunniest, warmest part of the day.
What's the best time of year to spot dragonflies?
In the UK, dragonflies are on the wing from as early as April to as late as November. They prefer warmer weather and are most active from June to August.
What is the difference between dragonflies and damselflies?
Although similar, dragonflies and damselflies are different species. Dragonflies (pictured above on the right) are larger and stronger fliers – often seen moving with speed, whereas damselflies (pictured left) can fly in a more fluttery fashion.
A damselfly larva is differentiated by its three leaflike gills on the abdomen. Dragonflies have internal gills. As adults, most damselflies tuck their wings vertically when not in flight, while dragonflies keep theirs open.
Damselfly eyes are widely separated on each side of a rectangular head; dragonfly eyes meet in the middle.
