Fluctuating river levels and fast currents are known to wash away dragonfly larva (or nymphs). As larva live underwater for up to three years, our unprecedented floods may have a long-term effect on dragonfly populations.
Peter Birch, group environment manager for the Canal & River Trust, explains: “Dragonflies, and their sister damselflies, flourish in clean water which is rich in bankside vegetation, such as reeds. This makes them a fantastic indicator of the health of a canal or river.
Healthy water environment
"While this year's floods have had an obvious impact on larger animals, birds and fish, we are also particularly concerned with the impact on invertabrates, which form the foundation stones of a healthy water environment. We would expect to see an increase in numbers of mosquitoes and midges which prefer stagnant and isolated water, but we may also see a drop in the numbers of dragonflies emerging this spring.
“By taking part in the Great Nature Watch, you can help us monitor numbers of dragonflies, damselflies, and in fact, all species living on our canals and rivers over the coming years."
Dragonflies are an ancient species, whose ancestors were around before the dinosaurs. While many of us recognise them as beautiful, iridescent, flying summer insects, they in fact spend the majority of their lives as underwater larva. They emerge ‘on the wing' for a few brief months to mate and lay their eggs before dying.
The Great Nature Watch asks you to record your sightings of all wildlife you see on a canal, river, reservoir or lake.