Amazingly, there are about 250 species of Hoverfly in the UK, but most of us will only have seen a few species in our gardens, if you can keep up with them! They are not all brightly coloured, bee and wasp impersonators, but can be dark in colour and harder to spot. Mimicking bees and wasps will warn off predators as this type of marking and colours normally depicts a stinging insects or one that’s bad to taste. This type of mimicry is called Batesian mimicry and is named after the naturalist Henry W Bates, who first published his idea in 1862 after discussing his idea with a certain Mr C Darwin. Hoverflies are true flies and are two winged insects of the Diptera order.
Hoverflies feed on nectar and pollen, and as their name suggests, have this amazing ability to appear motionless in the air, then dart off quickly before hovering again. The young larvae vary in behaviour and appearance. They can be either vegetarian, feeding on vegetation, or carnivores feeding on aphids. So there are good reasons for attracting them to your garden! You can see these amazing insects from March to November, depending on the species.
One of the most common species you’ll see is the Marmalade Hoverfly Episyrphus balteatus, and I was lucky to spot a Hoverfly mimicking a white-tailed bumble bee Volucella bombylans, here in The Lodge gardens; the compound eyes were a tell-tale give away. A compound eye consists of hundreds or thousands of photoreceptors on a convex surface, creating a large viewing angle that can identify fast movement (the eyes appear to almost touch in the middle). Unlike wasps, Hoverflies don’t have a sting and are completely harmless. They are important pollinators, but are unable to carry as much pollen as bees do, but more frequent visits help to make up for this.
Marmalade Hoverfly - Chris Sheilds (rspb-images.com)
You can help these agile flyers by having lots of flowering plants in your garden all through the summer. Don’t think that gardens on a grand scale are the only ones to attract these fascinating creatures. You can garden in pots and containers having bulbs flowering early in the spring, with shrubs and bedding plants through the summer months and into autumn. Your local garden centre will advise you on what’s in season and what will grow well in containers, but for more ideas take a look at our gardening for wildlife pages on our web site (see link).
http://www.rspb.org.uk/advice/gardening/planting/index.aspx