A global review, published in Biological Conservation has shown that 40% of the world’s insect species are at risk of extinction over the next few decades, with butterflies and moths most affected.
The analysis reviewed 73 historical reports of insect declines and found the main drivers of species declines to be: habitat loss and conversion to intensive agriculture and urbanisation; pollution, mainly that by synthetic pesticides and fertilisers; pathogens and introduced species; and climate change. The authors note that climate change is mostly an issue in tropical regions.
While declines are affecting both specialist and generalist species, a small number of adaptable species are increasing.
The decline of insect populations will have severe knock-on effects, such as: reduced food availability for other taxa, loss of pollination services and altered soil processes. The authors warn that this “will have catastrophic consequences for both the planet’s ecosystems and for the survival of mankind.”
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