Why Insects Matter

There will be no life on earth without insects.

Late in the day we recognise how vital insects are to the functioning of our eco-systems. We have woken up to the frightening fact that as pollinator numbers diminish so do plants dependent on them for producing their seeds and that birds are in trouble because of the decline of insects. In spring your garden Great Tits feed their young entirely on these diverse creatures.  Insects, strange, beautiful and ingenious, with their wealth of species, form an essential foundation for all life. Some of us still think of insects with revulsion because we have been brought up on horror films like Killer Bees or scared by ideas of biblical plagues of locusts but this is a misrepresentation of these remarkable forms of evolution. They provide the great food chains that sustain life.  Even mosquitoes provide food for fish and dragonflies in their larval form and as adults feed aerial birds like swifts.  Caterpillars, aphids, caddisfly larvae and grasshoppers are herbivores turning plant material into tasty insect protein, eaten by larger animals. Wasps and ground beetles keep the herbivores in balance by predating them.All are prey for a multitude of birds,bats, spiders, lizards,frogs, small mammals and fish like salmon and trout.

 Insects are characterised by having a head, thorax and abdomen and six jointed legs. They also have a pair of antenna, compound eyes and a sturdy exoskeleton. Tom Massey, this year, designed a garden for the Royal Entomological Society at Chelsea to celebrate insects as part of gardens. At the garden’s centre is a compound insect eye lab, where children can study insects and become the next generation of insect scientists. Children were discovering marvellous beetles amongst rotting wood and palisades of dead leaves. Tom was embracing plants like dandelions and thistles that are a great source of nectar for insects.

Insects pollinate flowers including those of fruit and grain, clean up organic matter like manure and control pests. The fly family and their maggots play a leading role in clearing up dead animal bodies such as deer and rabbits so that the cadaver swiftly becomes bones and scraps of fur.

Soil dwelling insects aerate the soil; ants disperse seeds; silk moths provide silk and honeybees honey. Britain’s leading gardening charity, the RHS, has just put wasps at the top of its list of beneficial wildlife because they are vital garden predators. Also on the list is the rose chafer beetle of a rich metallic green. Its larvae feed on decaying plants, helping with the composting process.  The majority of us ignore the marvel of insects, although canny drug companies have begun ‘bio-prospecting’ the almost infinite number of chemical compounds found in them, some with the potential of tackling antibiotic resistant bacteria.

Dave Goulson’s devastating account of the decline of the insect population, “Silent Earth”, is a passionate argument for us to love, respect and care for our insects and to understand that insects, flowers, plants, trees, birds and mammals – including us – are a single system. Are we willing, he asks, to condemn our grandchildren to a world where the sight of the first brimstone butterfly in Spring is no longer possible, where the sound of bumble bees buzzing among flowers cannot be heard. We are in danger of living in a dreary, perilous and impoverished world.  Our magnificent Norfolk Swallowtail butterfly is now threatened by climate change.  As Goulson says, “We have to live in harmony with nature, seeing ourselves as part of it.” Our survival depends on it.

What We Can Do

• Have a wide variety of wild and domestic plants in the garden without using pesticides.
• Grow flowers rich in nectar to support pollinators like bees, butterflies and hoverflies.
• Grow food plants for the larvae of butterflies and moths: lady’s smock, nettles, bird’s foot trefoil, ivy.
• Reduce how often you mow and allow your lawn to flower. See what grasses and flowers appear. See your weeds for the wild flowers they are.
• Dig a pond with soft-sloping sides and watch for dragonflies and whirligig beetles.

Sources

Silent Earth, David Goulson, 2022, Vintage Publishing.

August 2023