Around half of all insects may have vanished since 1970, with over 40% threatened with extinction, according to a new report warning that drastic declines in insect numbers look set to have far-reaching consequences for wildlife, people and the food industry.
The report highlighted habitat and pesticides as the main reasons why pollinators and other insects are dying.
“Over the last century, natural and semi-natural habitats have been cleared at an accelerating rate to make way for farming, roads, housing estates, factories, lorry parks, golf courses, shopping centres and a multitude of other human endeavours…[Today] many important insect populations [only] persist on small, highly fragmented and isolated islands of habitat,” it said.
The report, which was commissioned by the UK-based conversation group the Wildlife Trusts, added around that ‘17,000 tonnes of poison [is] broadcast across the [UK’s] landscape each year.’ It said much of this is associated with intensive farming, but the report also highlighted the destructive capacity of domestic usage, where ‘numerous insecticides, fungicides and herbicides are freely available from garden centres, DIY stores and even supermarkets’.
The report said 23 bee and wasp species have become extinct since 1850. UK butterflies that specialise in particular habitats have fallen 77% since the mid-1970s and generalists have declined 46%, it added.
Invertebrate expert, Dave Goulson, Professor of Biology at the University of Sussex, author of the analysis, said: “Insects make up the bulk of known species on earth and are integral to the functioning of terrestrial and freshwater ecosystems, performing vital roles such as pollination, seed dispersal and nutrient cycling. They are also food for numerous larger animals, including birds, bats, fish, amphibians and lizards. If we don’t stop the decline of our insects there will be profound consequences for all life on earth.
“And it’s not just our wild bees and pollinators that are declining – these trends are mirrored across a great many of other invertebrate species. Of serious concern is the little we know about the fate of many of the more obscure invertebrates that are also crucial to healthy ecosystems.
“What we do know however is that the main causes of decline include habitat loss and fragmentation, and the overuse of pesticides. Wild insects are routinely exposed to complex cocktails of toxins which can cause either death or disorientation and weakened immune and digestive systems.”
The report concluded: “The consequences are clear; if insect declines are not halted, terrestrial and freshwater ecosystems will collapse, with profound consequences for human wellbeing.”
Insects help provide us with much of our food - even cheeseburgers
According to Friends of the Earth, which produced its own report last year highlighting the declining insect population, insects play a pivotal role in the complex web of life, including helping provide us with much of our food. It blamed the insect decline on the combined effect of several drivers especially ‘the direct loss of their natural habitats in both town and country, inclement weather and a changing climate, and exposure to harmful chemicals’.
“Flying insects have really important ecological functions, for which their numbers matter a lot. They pollinate flowers: flies, moths and butterflies are as important as bees for many flowering plants, including some crops. They provide food for many animals – birds, bats, some mammals, fish, reptiles and amphibians. Flies, beetles and wasps are also predators and decomposers, controlling pests and cleaning up the place generally,” said Dr Lynn Dicks from the University of East Anglia in the report.
Friends of the Earth added that that insect decline is likely to impact food production simply because of a lack of bees and other beneficial insect pollinators to pollinate crops. “Natural pollination is shown to support crop production and to boost the quality of food produced,” it said.
It added that in a world without bees and other insects that currently pollinate for free, insect decline would also affect food prices. “Farmers and growers would have to pay to artificially pollinate their crops, passing that extra cost on to consumers,” it stated.
Around one third of all food can be put down to the pollination work performed by insects, according to Insect Respect, a group which promotes projects and products that enhance the value of insects. Fruit-producing plants, low-growing fruits and vegetables are unimaginable without insects, it said. “Without insects, even a cheeseburger would only be a bread roll, because cows prefer eating forage crops that have been pollinated by insects.”
The unnoticed apocalypse
Dr Gary Mantle MBE, Chief Executive of Wiltshire WildLife Trust said: “This unnoticed apocalypse should set alarms ringing. We have put at risk some of the fundamental building blocks of life. But as this report highlights, the main causes of insect declines are known and we can address them; insects and other invertebrates can recover quickly if we stop killing them and restore the habitats they require to thrive. But we all need to take action now in our gardens, parks, farms, and places of work.”
Josie Cohen, Head of Policy and Campaigns for Pesticide Action Network, added: “Reducing pesticide use is a challenge that society can no longer ignore. We applaud the Wildlife Trusts and others for highlighting that routine overuse of pesticides is harming wildlife and the ecosystems that underpin our health and prosperity. If the UK government is serious about its commitment to “leave the environment in a better state than we found it” then it urgently needs to adopt measures which drive a massive decrease in pesticide use. We need an ambitious pesticide reduction target accompanied by a package of support for farmers to help them transition to non-chemical alternatives.”