The decline of insects could cause a "catastrophic collapse" of nature: study

Human activity is causing a dramatic drop in the number of insects, which could result in the extinction of 40% of species within a few decades, warned a scientific study.

The global review of the dwindling number of insects warned that the world was witnessing the "greatest extinction event in the world" for millions of years, facing the loss of life. Habitat, pesticides, diseases and invasive species, and climate change.

Because of the importance of insects for natural systems and other wildlife, "such events can not be ignored and should prompt decisive action to prevent a catastrophic collapse of natural ecosystems," scientists warned.

The review, published in the journal Biological Conservation, examined 73 historical reports of insects from around the world, including studies in the UK, and found that insects ranging from butterflies to bees to beetles were among the most more affected.

Declines did not only affect specialized species, for example those that depend on a particular host plant or live only in specific habitats, but also much more "generalist" species.

The researchers warned that the intensification of agriculture over the last six decades was "the root cause of the problem" and that the relentless and widespread use of pesticides was having a major impact.

Habitat loss and conversion of land to intensive and urban farming areas, followed by pollution, mainly by chemical pesticides and fertilizers, are the main causes of insect decline.

Insects are also affected by biological factors, such as pathogens and introduced species, and by climate change, where rising temperatures could affect the diversity of places where they can live.

Insects are essential to the functioning of natural systems, from providing a food source for other wildlife species such as birds, mammals and amphibians, to pollinating plants and recycling nutrients.

Researchers Francisco Sanchez-Bayo and Kris Wyckhuys said: "The conclusion is clear: unless we change our methods of food production, the insects as a whole will disappear on the path of extinction in a few decades.

"The repercussions this will have on the planet's ecosystems are, to say the least, catastrophic, since insects are the structural and functional base of many global ecosystems since their rise in the late Devonian, there are nearly 400 million of them. 39, years. "

They called for habitat restoration, a dramatic reduction of pesticides and changes in agriculture to help insects, such as flower-rich strips planted along fields or the rotation of crops. crops with clover for the benefit of bumblebees.

Matt Shardlow, Managing Director of Buglife, a wildlife charity, said, "It is extremely disturbing to see this collection of evidence that demonstrates the deplorable state of insect populations around the world.

"It's not just bees, or even pollination and feeding, but declines also include beetles that recycle waste and insects like dragonflies that start life in rivers and ponds.

"It is becoming increasingly clear that the ecology of our planet is being crumbled and it is necessary to deploy intense and global efforts to stop and reverse these terrible trends. Allowing slow eradication of insect life is not a rational option. "

He said insects accounted for more than half of the species on Earth, but research has shown that they disappear much faster than birds and mammals.

"There is not a single cause, but the evidence is clear: to end this crisis, we must urgently reverse habitat fragmentation, prevent and mitigate climate change, clean up polluted water and replace pesticide dependence with more sustainable and environmentally friendly agriculture, "he said. urged.