Summer was with us last Saturday as we greeted visitors to our Dragonflies event at Anton Crescent Wetlands. This year has been notoriously bad for flying insects but with a few days of sunshine behind us we had high hopes. Odonata (dragonflies and damselflies) are cold-blooded animals and without sunlight the larvae lose energy and are easily predated. The adults are also solar-powered and need to keep warm so they can hunt and find mates.
Dragon and damsel flies spend most of their life as larvae, with some of the largest species spending up to seven years underwater! When they are ready, they climb out of the water and emerge from their larval skins as full adults. The left-over shells are known as “exuviae” and, if found, are great indicators of breeding activity. We were hunting for their larvae today, armed with nets, trays and a pond-dipping platform. Our first sweep yielded a variety of water fleas, backswimmers and even a little newt. Within a few minutes we had also sighted what was most probably a Common Darter (Sympetrum striolatum) flitting across the pond.
While the youngsters were busy investigating the pond, one of the staff members decided to take a jolly with the butterfly net. The meadow grass was full of life, with field grasshoppers chirring away and bees, hoverflies and butterflies making their daily commute around the goat’s rue (above left), ragwort and willow herbs (right). Two mating Common Blue damselflies were also spotted over the pond.
So, how do you tell the difference between dragonflies and damselflies? With dragonflies, think BIG. They have large eyes that usually meet in the centre, stocky bodies and dissimilar wings (the hind wings are broader at the base) that are either held open, horizontally or downwards at rest. Damselflies, as their name suggests, are daintier than dragonflies and much weaker in flight. Their eyes are clearly separated and they have uniform wings that are closed at rest, usually over the abdomen.
Both dragonflies and damselflies have voracious appetites and will happily keep mosquito numbers down, making them an even more attractive addition to gardens and parks. If you want to attract some of these mythical insects into your grounds, make sure you provide them with the basics. As with most creatures, they require a fresh water supply and foraging areas. As they spend a lot of time as larvae, ponds in a sunny position that are at least 2ft deep will provide shelter and protection from predators all year round. Nearby areas of wildflowers will provide the necessary hunting grounds for insects while sticks or shale located around the pond will act as recharging stations for your cold-blooded visitors.
DRAGONFLY SPOTLIGHT by Arthur Lovatt
The Broad-Bodied Chaser
The Broad-bodied Chaser (Libellula depressa) is a common dragonfly native to Europe and Asia. It is distinguishable due to its very broad flattened abdomen, four wing patches and, in the male, the abdomen becomes pruinose blue.
Both male and female dragonflies have broad, flattened abdomens which are brown with yellow patches down the side. The males, however, develop a blue colouration to the abdomen, which covers up the brown. The average wingspan of L. depressa is around 70mm. These distinctive qualities mean the Broad-bodied Chaser should not be easily confused with other dragonflies.
The Broad-bodied Chaser inhabits central and southern Europe, central Asia and the Middle East. It is known to be found as far North as Southern Scotland, Southern Sweden and Southern Finland and as far South as Corsica, Sardinia, Sicily and Menorca. This is the extent of its range as it does not go further south from Europe into Africa. They feed on insects and generally inhabit lakes and ponds but also migrate. Adults undergo a period of maturation when they are away from water after emergence from larvae. They are mainly seen in May and June, are territorial and have a favoured perch to which they often return. Laid eggs hatch in 4 to 5 weeks and it takes 1 to 2 years for larvae to fully develop.