The Link Late Summer 2019 The Link Aug-Sep 2019 v2 | Page 16

Heineken hoverfly (Rhingia campestris): photo courtesy of Chris Lawrence B ees famously play an essential part in natural ecosystems, with a notable role as pollinators. But did you know that wild pollinators generate the same kind of economic value as managed honeybees, approximately one third of the UK total? Or that our second most important pollinators after bees are hoverflies? Britain has more than 280 species of hoverfly, which frequently visit flowers for nectar and pollen. Hoverflies article by Kate Basley, Surrey Wildlife Trust Many hoverflies are masters of mimicry. One of our most common species, Eristalis tenax, is also known as the drone fly because of its striking resemblance to the male honeybee. This similarity is the result of an evolutionary process known as Batesian mimicry, where a harmless species develops a coloration pattern similar to that of a harmful one, thus deterring predators. However, there are two easy ways to tell between a hoverfly and a wasp or bee. One is to look at its antennae: bees have relatively long antennae compared to the shorter, stumpy ones of the hoverfly. Another is to count the number of wings: bees have four; hoverflies have two. Some species of hoverfly, such as the marmalade fly Episyrphus balteatus, the most common UK species, are valued by gardeners because their larvae eat aphids. They are easy to identify by their orange body with thick and thin bands across it. Females lay their eggs 16 To advertise call 01684 833715 or email: [email protected]