On the Wildside: The ‘Footballer’ pays a visit to the garden pond

The large-eyed adults feed on nectar and pollen especially seeking out flowers like common hogweed, angelica, or other umbellifers. These often rather striking insects are harmless, and whilst many look superficially like a wasp or a bee, they don’t sting. Sometimes quite large and actively buzzing around, then people sometimes worry that they might! Appearing wasp-like is an evolutionary adaptation to discourage would-be predators and many species are strongly marked with yellow and black or orange and black stripes.

The larvae are rather variable and feed and grow in a wide range of habitats from dung, to rotting wood, to water-bodies, and they include the well-known ‘rat-tailed maggots’ found in still, organically-polluted waterbodies. Terrestrial species include ones that are the gardener’s friend in that they eat aphids (i.e., greenfly). The habitat specificity and the ease of spotting and identifying hoverflies mean that they are used as so-called ‘indicator species’ for habitat quality. The adult flies will be seen hovering in a favoured sunny spot where they may defend their patch and seek out suitable mates. They mix being almost stationary with frequent and sudden darting movements as they detect a would-be mate or perhaps a rival.

The ones pictured around my garden pond are a Helophilus species, known as the ‘Footballer’ (because of the striped thorax) including marsh tiger, large tiger, and others. I think the ones pictured mating are probably marsh tigers, strongly associated with the emergent pond vegetation, and their larvae will be rat-tailed maggots in the pond. The adults generally only live for a few days to a matter of weeks and there may be several generations of larvae. These leave the water when mature to pupate in soil nearby. Adults have pollen-gathering body-hairs collecting pollen whilst they sip nectar, the pollen being groomed off using the legs and transferred to the mouth.

Professor Ian D. Rotherham, researcher, writer & broadcaster on wildlife & environmental issues, is contactable on [email protected]; follow Ian’s blog (https://ianswalkonthewildside.wordpress.com/) and Twitter @IanThewildside