Dragonfly-like insects have been taking to the skies for around 350 million years. Their ancestors – insects called ‘griffinflies’ – would have been patrolling the swamps before dinosaurs roamed the Earth. They would have looked much the same as our dragonflies today, except that they were giants with wingspans in excess of 70 centimetres!
Whilst the modern insects are smaller, they are still ferocious, the ultimate predator of the insect world. Dragonflies have phenomenal powers of sight, flight and manoeuvrability. Their light yet strong wings are powered by large muscles, and they can reach speeds up to 36 kilometres per hour, they can hover and fly both forwards and backwards.
Their compound eyes, with several thousand lenses, afford the dragonfly with excellent colour vision and acuity and they can see almost every angle except right behind them. Combined with bristle-covered legs and razor-sharp mandibles, these features make dragonflies fearsome predators with a 90% ‘hit rate’. A single dragonfly can eat 30 – 100 mosquitos per day!
Most of a dragonfly’s life – perhaps as much as 95% of it – is spent in the water. The eggs are usually laid underwater, develop into water-dwelling nymphs from which the adult eventually emerges. The whole process may be completed within six months, but for most species takes several years. In contrast to the larvae, the adults are generally short lived – perhaps a few weeks or a month.
The variety of habitats here makes it great for dragonflies – river valleys, wetland ditches, ponds and boggy heathland - pick a sunny day and head out to find some of these most spectacular of insects.