Damsels and chasers

My head’s a whirl of chasers, hawkers, darters and skimmers - all the result of a morning spent admiring dragonflies! On a hot Saturday morning a party of WNS members met representatives of the British Dragonfly Society at the Otley Wetlands Nature Reserve; our aim to search out and identify as many dragonflies and damselflies as possible. Oystercatchers piped from the lakeside, a proud pair of swans shepherded their four small grey cygnets across the water, a reed warbler chattered from the reeds and everywhere you looked electric blue damselflies darted about among the vegetation or shimmered over the water. A perfect day for our quest.

As well as the common blue damselflies, we saw emerald damselfly - harder to pick out as it clung to a grass-blade - and, my all-time favourite, the banded demoiselle. From a distance this looks rather like a black butterfly as it flickers over the water but, get closer, and you see its wings are banded with rich midnight blue; closer still, or see it perched as we did, and you’ll marvel at the blue and emerald body glittering as though it had been brushed with gold-dust. An exquisite piece of jewellery, but alive and dancing in the sunshine.

Damselflies are the smaller cousins of dragonflies. They look rather like brilliantly coloured darning needles, red or blue or green, as they dash around over or near the water. Dragonflies are fierce predators and have various strategies for catching their prey, so species are categorised as hawkers, chasers, darters, skimmers etc. The commonest species that morning was the brown hawker. It fairly whizzes around over the waterside vegetation, its barley sugar brown wings glinting in the sunshine. Another hawker, and the big excitement for me, was a fine emperor dragonfly patrolling its chosen stretch of water in a series of rapid circuits: hawkers are large, and this one is our largest hawker. It’s resplendent in blue and green with a wingspan of over three inches - a relative newcomer to our area. The chasers and darters give you a better chance to see them in detail as they often perch on stones or vegetation. We saw several broad-bodied chasers, their light blue abdomens slightly flattened, as though they’d been squashed, and four-spotted chasers, more lightly built with the characteristic four black marks on the wings.

Admission to the OWNR is by permit only, but Wharfedale has lots of tarns, ponds, rivers, streams and reservoirs where you can encounter a dragonfly. When you do, you might reflect that this stage of swoop, zip and dash is just the final, and shortest, stage in its life: after a year or more spent in larval form in water it clambers out, splits the larval skin and emerges as this complex insect. After a few hours’ necessary rest (there’s no need for learning or practice) it’s immediately ready to skim and loop the loop in its new environment of air. And just think, there were dragonflies skimming and hawking amid the tree-ferns and giant horsetails long before the dinosaurs trod the earth - and some of them were huge!

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