10 things you didn’t know about hoverflies

They work as hard as bees to pollinate our plants, often look and sound like bees but have no sting – yet hoverflies remain the unsung heroes of our gardens.

Now, The Wildlife Trusts and the Royal Horticultural Society (RHS) are calling on gardeners across the country to help save hoverflies, through this year’s Wild About Gardens campaign, by making room for these beneficial insects in our gardens this summer by building log piles, planting flowers and creating shallow ponds.

Hoverflies come in many shapes and sizes and are often mistaken for bees, wasps and hornets. Many of these insect workers, which are as critical for our food security as bees, are now endangered, the charities warn.

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They visit 72% of crops globally which they either pollinate or protect by eating sap-sucking aphids.

Additionally, they pollinate wildflowers, are food for birds and even help break down organic matter in gardens.

Yet, intensive agriculture, harmful pesticides, urban development and climate change have all taken their toll, the charities state.

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“Hoverflies contribute so much to our gardens and pollinate more than half the world’s crops,” says Vicki Hird, strategic agriculture lead for The Wildlife Trusts and author of Rebugging The Planet.

“Unfortunately, just as with bees, harmful pesticides, urban development, climate change and intensive agriculture are threatening their survival.

“One thing we can all do this summer is to make our gardens more hoverfly friendly. If you invite them, they will come – and once you start to notice them, you’ll be amazed at their incredible markings and cunning disguises.”

Helen Bostock, senior wildlife specialist at the RHS, says: “You can attract hoverflies by planting open, easily accessible flowers. In spring, they’ll be drawn to aubrieta. In summer, they’ll love blackberry flowers, oxeye daisy, marigolds, fennel, cow parsley and poppies. Come autumn, they can be seen on heather, aster and even common ivy.”

10 things you may not know about hoverflies:

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1. There are around 280 species of hoverfly and they’re the second most significant pollinator after bees.

2. Some hoverfly species are masters of disguise. They have assumed the form of stinging insects to protect themselves. The hornet mimic hoverfly is the UK’s largest hoverfly, at almost 2cm long.

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3. The adult insects tend to be black and yellow with oval bodies, but they may have white markings or even a metallic sheen. Common names include the Footballer, Batman and Marmalade hoverfly due to their colours, stripy patterns and markings.

4. Hoverflies, like other flies, have a single pair of wings, whereas most other flying insects have two pairs. They also move differently to other insects, zigzagging and hovering around plants and crops which they’re attracted to.

5. The eyes of male hoverflies will meet in the middle of the head. If there’s a gap, it’s a female. There are also behavioural differences: some male hoverflies will defend a patch of sunlight, claiming it as their territory and waiting for passing females.

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6. Just like a butterfly or moth, hoverflies have a four-stage life cycle. Their eggs look like tiny grains of rice and their larvae are maggot-like with no obvious legs or head. The pupa is hidden in a sheltering skin which, in some species, resembles a tiny pear.

7. When birds migrate, it’s a two-way trip. Insect migrations are generational journeys. An adult hoverfly may fly to the UK to lay eggs, and its offspring could then head south to Europe. Research shows that every year 17 million insects heading south pass through a single 30-metre gap in the Pyrenees, many of them pollinating flies.

8. Without hoverflies and other pollinators, biodiversity would decrease, our flowers would be at risk and our gardens would be less productive. We’d have fewer berries, seeds and fruits such as apples and strawberries.

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9. Hoverflies also provide food for birds and many help break down organic matter in our gardens.

10. A UK Government report states that the overall distribution of hoverflies has declined by 44% between 1980 and 2022. In 2022 the International Union for the Conservation of Nature added 37% of European hoverfly species to its Red List, a list of species threatened with extinction.

Homespun projects to attract hoverflies

Experts from the two charities have designed a series of step-by-step projects anyone can do to create havens for hoverflies in gardens or outdoor spaces. These include:

Pollinator plant boxes: Ideal for small-space gardens or balconies, these can be packed with flowering plants to suit the season, creating a buffet for visiting hoverflies.

Hoverfly lagoons: These are pools of shallow water where fallen leaves form an ideal breeding ground for many of the hoverfly species which have aquatic larvae.

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Larvae nurseries: Log piles and shrubs can make perfect homes for hoverfly larvae.

For project guides and a hoverfly spotter sheet, visit wildaboutgardens.org.uk.