The “unnoticed insect apocalypse” should set alarm bells ringing, according to conservationists, who said that without a halt there will be profound consequences for humans and all life on Earth.
A new report suggested half of all insects may have been lost since 1970 as a result of the destruction of nature and heavy use of pesticides. The report said 40% of the 1million known species of insect are facing extinction.
The analysis, written by one of the UK’s leading ecologists, has a particular focus on the UK, whose insects are the most studied in the world. It said 23 bee and wasp species have gone extinct in the last century, while the number of pesticide applications has approximately doubled in the last 25 years.
UK butterflies that specialise in particular habitats have fallen 77% since the mid-1970s and generalists have declined 46%, the report said. There are also knock-on effects on other animals, such as the spotted flycatcher which only eats flying insects. Its populations have dropped by 93% since 1967.
“We can’t be sure, but in terms of numbers, we may have lost 50% or more of our insects since 1970 – it could be much more,” said Prof Dave Goulson, at the University of Sussex, UK, who wrote the report for the Wildlife Trusts. “We just don’t know, which is scary. If we don’t stop the decline of our insects there will be profound consequences for all life on earth [and] for human wellbeing...70% of Britain is farmland. No matter how many gardens we make wildlife friendly, if 70% of the countryside remains largely hostile to life, then we are not going to turn around insect decline.”
Studies of insect populations over decades are scarce, he said: “But the overwhelming weight of evidence that exists suggests the rapid decline is a real phenomenon. It really worries me to hear people say we need more long-term studies to be sure. That would be great, but we can’t wait another 25 years before we do anything because it will be too late.”Insect population collapses have been reported in Germany and Puerto Rico, and the first global scientific review, published in February, said widespread declines threaten a “catastrophic collapse of nature’s ecosystems”.
Virtually all farms could significantly cut their pesticide use while still producing as much food, according to a 2017 study. The research also showed that chemical treatments could be cut without affecting farm profits on three-quarters of farms.