Vanishing act in Europe and North America

What we know, and don’t know

Preliminary research in Europe and, to a lesser extent, in North America points to a decline in the abundance of numerous insect species, seemingly across families and habitats. And what we know from Europe is that overall abundance, at least in countries like Germany and the Netherlands, has plunged precipitously in just a few decades — even in nature reserves.

“I think this [serious loss] fits into all the other alarm bells that have been ringing for us and society lately,” Trautwein says. “The potential drivers of [the insect decline] are things that are causing major issues for society and for ecosystems more generally: climate change, habitat destruction, pesticide usage … This is all added evidence that we need to start taking this [mass extinction crisis] seriously.”

Indeed, because everything in the web of life is connected, and because the slashing of one thread leads to the weakening of the whole, crashing insect abundance is almost certainly linked to other ecological degradations occurring on our planet.

“All of a sudden you start looking at nature in a different way because the things that have been changing could very well be changing as a result of this insect decline,” says de Kroon. For example, insect decline may also explain losses among insect-eating birds, lizards and amphibians.

In the end, we are left with far more answers than questions. For example, how are insects faring on the rest of the planet, where research dollars are spread much more thinly, especially in the tropics of Africa, Asia and Latin America? It’s here that insect diversity stands unparalleled, with most species still unknown to science. But, to date, we have only a single major tropical study on just one protected area on a solitary island in the Caribbean, though we may soon have more.

“Things are in much, much more dire straits than I ever thought. I think the time has come to start using stronger terms,” concludes Lister. “When I saw [the headline] ‘Insect Apocalypse is Here’ [in the New York Times]… I thought, ‘Oh, my God, this isn’t good.’ You know how scientists don’t want to oversell or [use] hyperbole? But now, yes, that’s a good term — a catastrophic collapse is what I’ve been saying lately.”


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Banner image of a pair of marsh tiger hoverflies (Helophilus hybridus) in Sweden by Axel Ssymank.

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