It is late afternoon and the muggy conditions cast a sultry feel. The
shade on the river provides some comfort and I stand and watch the river from
the stone bridge that marks an ancient crossing point. The water is running
clear again after the rain of earlier in the week and the waterweed ripples in
the slowly moving current. Towards the bank, where a shaft of sunlight cuts
through the shadow cast by the bank-side trees, a school of small fish dance
and glint just below the surface. I have seen pike here and suspect that the
small fish face an ever-present threat.
A movement catches my eye, as from the shadows emerges the jewelled blue
of a banded demoiselle, the county’s most stunning damselfly. This species
favours slow moving rivers and the male is easily recognised by wing band of
brilliant blue. Only the male beautiful demoiselle is more stunning but, alas,
it does not occur this far east. The male banded demoiselle has a blue body,
dark legs and robust, paddle-shaped wings. The female is emerald green, her
wings with a pale green hue but sporting no band.
This male is not alone; arcing out across the water he dances around
another male that has just appeared from under the bridge. The two protagonists
circle each other, seemingly displaying with a fluttering flight that is
reminiscent of a butterfly. Even though there is no contact between them, I
lose sight of which was the original male but assume it is the one that has
looped back to the shadows from where it first emerged.
Alone among the British damselflies, it is only in our two demoiselles
that courtship behaviour has been confirmed, the male responding to the
presence of a female with a simple display in which he raises his abdomen and
opens his wings. If she is receptive to these advances she will communicate
this by alighting near the male. He will then perform an aerial dance in front
of her, first moving backwards and forwards and then from side to side. If the
female remains receptive then he will approach and land, perching on her wing
tips and then climbing slowly down onto her abdomen. It is then that he takes a
grip on her to adopt the characteristic ‘tandem position’, something that you
may well have observed in other damselflies.
These damselflies are a thing of beauty, so delicate that it is
difficult to equate them with the squat larvae hauled from the silty root
masses of waterside vegetation. The adults make a forlorn sight when you come
across them on the nearby road, a life extinguished that should have been dancing
jewel-like above the river.
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