What we owe to insects

‘Entangled with their host plants, insects are helpless as we fragment and destroy their habitats’

Lisbet Rausing

Insecticides indiscriminately kill insects. Unsurprisingly so. That, after all, is what they are made to do. The agrochemical companies put on a show of being flabbergasted by this, but that is mere persiflage. They know, as we do, that poison does not discriminate between agricultural pests and farm helpers.

And therein lies the problem. Insects are keystone species. Without them, nature’s fine-spun ecological web unravels. Insects labour silently: airing soils, removing dung and dirt, hunting other insects and grazing plants. They make food for birds, fish, frogs and bats. Bees and butterflies are co-evolved sexual partners to flowers, including many flowering crops.

Yet scientists now speak of an insect apocalypse. Perhaps 40 per cent of insect species in Europe and North America face extinction. In Britain, wild bees and hoverflies are disappearing over vast areas. Insects, after all, are highly specialised. They live in their own little world. Our flower patch is their jungle.

Entangled with their host plants, insects are helpless as we fragment and destroy their habitats. Insecticides have devastated them and climate change, too, threatens these tiny, small-range critters. Yet we need insects: to pollinate plants, regenerate forests, fight crop pests, and feed birds and animals. They are the base of the ecological pyramid.

Insects are also essential to healthy farm soils. But few conventional farmers ask themselves how their chemicals affect living soils’ invisible, mutualistic dance, below and on the surface of their fields. In fact, most farmers barely know their fields’ multi-species soil symbioses. We farm blind.

We spray insecticides over our fields and bury them in our soils (when we plant  pesticide-coated seeds). How do these toxins affect beneficial soil organisms—viruses, bacteria and protozoa, ground beetles, spiders, millipedes, springtails, earthworms, roundworms and mites? How do they affect mycorrhizal fungi? And what is the soil biota effect of heavy tractors compacting our fields (flattening and crushing these critters’ homes)? Of nitrogen-drenching fields?

We still don’t know all the details. But we do know that soil organisms die as we compact, plough, spray and fertilise. We also know that we crucially depend on these life forms to keep farm soils healthy: they recycle organic materials into humus, capture carbon and feed minerals to crop plants. And their little burrows and tunnels loosen soils, retaining water by improving drainage.

With climate change Britain’s rainfall grows more erratic and intense. At the same time, thanks to our poor soil management, entire regions of Britain are seeing their effective rainfall—the water soils can hold and absorb—plummet. We create “wet deserts” as water sheet-flows off dying soils—rock-hard, bare, overgrazed or ploughed ground—instead of seeping into vegetation-covered, soft, living soils.

Again: soils are alive. One tablespoon of healthy soil has more organisms in it than there are people on earth. When we kill soils, we kill hugely complex ecosystems we have not even begun to understand. And as our farm soils erode, compact, toxify and deplete, Britain’s nature and wildlife suffers.

Insecticides, for example, kill birds by starving them as insects disappear. But they also poison birds directly. That may be why farmland birds are particularly hard-hit in the West’s extinction crisis. In the US, 74 per cent of farmland birds are in decline. By 2013, Britain had less than half the farmland birds of 1970. In Europe, farmland bird numbers fell by 48 per cent between 1980 and 2006. Across Canada and the US, there are today an astonishingly three billion birds fewer than in 1970. That is 30 per cent fewer, and numbers keep on falling. Even America’s pushy and adaptable starlings have declined by 63 per cent.

And no wonder. Birds of our cultural landscapes—our farm companions—are universally exposed to a wide array of toxins. All sparrows test positive for cocktails of neonicotinoids. We know that these birds lose significant bodyweight, and become disoriented and confused, from eating a mere one-tenth of an insecticide-treated maize seed. As anyone who feeds garden birds knows, a hopeful and hungry sparrow (or for that matter any bird) will not stop at a one-tenth of a seed. It will innocently stuff itself on your peanuts—or, in farmers’ fields, on toxic treats.

Since Rachel Carson’s Silent Spring was published in 1962, the world’s use of pesticides has quadrupled to over five million tonnes in 2017. And that is not only because more farmers in poor countries now spray. Pesticide use is ever-increasing also in rich countries. In Britain since 1990, pesticide-sprayed lands have risen by more than half: the chemicals used are ever more toxic, and the numbers of sprays per year have gone up.

No wonder that Britain’s moths and butterflies are now in steep decline. Indeed, pesticides are a significant threat to all British nature: soil biota, insects, birds, fish, frogs and small mammals. What hubris we humans have.

In 2015, a Lincolnshire farmer harvested the highest wheat yield ever recorded in the UK, 16.5 tonnes per hectare. That crop was sprayed with four different weed killers, one insecticide, five plant-growth hormones, and 12 different fungicides. Nearly a third of a tonne of ammonium nitrate per hectare was applied. The then Secretary of State for Environment, Food and Rural Affairs, Liz Truss, praised this exceptional yield. But why? We are not the Soviet Union. What matters is not yield per hectare, but profit per hectare. And poisons are expensive.

Britain’s arable farmers make miniscule profits. If you deduct farm subsidies, most are in the red. But if the polluter paid—if farmers were invoiced for the environmental damage they cause—they would go bankrupt overnight. You might regard the fact that we don’t as a giant subsidy. Or you might think of it as ecological crime. But that is unfair to farmers. Hard-pressed British farmers are thanklessly slaving away for food corporations and the agrochemicals industry. However we frame the crises of British arable farming, it is not the farmers’ fault. British farmers are decent people who follow the law. Politicians make the law.

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