Dragonflies – prehistoric jump jets

Dragonflies are extraordinary creatures. They can fly at great speed and change direction in the blink of an eye, flying backwards or sideways as easily as forwards. Their acceleration makes a Harrier jet look sluggish.  Their eyes are enormous, complex, and may contain as many as 50,000 lenses. They’ve been on earth for two hundred and fifty million years and those we see today are recognisably similar to their prehistoric ancestors.

Migrant Hawker. Photo: Steve Cooke

The largest dragonfly in Britain – the Emperor – is almost 8 cm long, with a wingspan of 10 cm. It’s a big insect and can look fierce, especially if you’re nervous of insects. In fact, all dragonflies are quite harmless to people, having no sting and no tendency to bite. Some species are very inquisitive and will approach you closely. Don’t be alarmed: just feel privileged and enjoy the close-up view.

Dragonflies are nearly always associated with water: rivers, streams, canals, lakes, ponds, bogs. But they wander surprisingly far in their search for food or mates – the only things they care about – so you may see them in your garden even if it’s not near water.

Banded Demoiselle

‘Dragonflies’ can mean anything from the big, boisterous hawkers to the tiny and delicate damselflies. Among  the latter are the graceful and dreamlike demoiselles, with a languidly floppy flight somewhere between a butterfly and a fairy.

The big dragonfly most likely to be found in gardens is the Migrant Hawker, a species about 7 cm long.  They are on the wing from late July to October. Males and females differ in colouring – the male dark with blue spots, the female brown with yellow spots. Both have one easy identification feature: on the large segment of their abdomen (‘fuselage’) just behind the wings there is a mark that looks like a golf tee.

Migrant Hawker (female)

The sight of a big hawker patrolling a stream on a bright summer’s day rivals anything nature has to offer. They are hypnotically beautiful.

If you like to be able to identify what you see, there are good books to help you. There’s also, of course, a huge amount of material on the web. The British Dragonfly Society’s website is a good place to start, with photos of all the 38 British breeding species and much more besides.

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