Insect extinction a major problem for humanity
That over a billion native animals perished in the current bushfires has been a hot topic recently. Apart from that statistic being itself food for thought it was a salutary reminder that it could push many species to extinction.
It also reminded me of another world-wide extinction crisis happening now. I’m referring to insects. Their extinction is a cause for concern in its own right, but as the Guardian Australia reported, “Plummeting insect numbers threaten collapse of nature”.
Some misguided souls might think the collapse of nature is no big deal, but it is, for our own species survival depends totally on the natural world. That’s a frightening thought, which provoked me to look further into the topic.
The world’s insects are hurtling down the path to extinction, threatening a “catastrophic collapse of nature’s ecosystems”, according to the first global scientific review, published in the journal Biological Conservation.
More than 40% of insect species are declining and a third are endangered, the analysis found. The rate of extinction is eight times faster than that of mammals, birds and reptiles. The total mass of insects is falling by a precipitous 2.5% a year, according to the best data available, suggesting they could vanish within a century.
Though the planet is at the start of the sixth mass extinction in its history through huge losses reported in larger animals, insects are by far the most varied and abundant animals. Apparently they outnumber humanity by 17 times.
Some may mistakenly feel their extinction is to be welcomed, as it will means less pesky flied buzzing around our heads. However, insects are essential for the proper functioning of all ecosystems, as food for other creatures, pollinators and recyclers of nutrients. And food for us.
The review strongly indicates the crisis is global. The researchers set out their conclusions in unusually forceful terms for a peer-reviewed scientific paper: “The (insect) trends confirm that the sixth major extinction event is profoundly impacting on life forms on our planet.
“Unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades,” they write. “The repercussions this will have for the planet’s ecosystems are catastrophic to say the least.”
Their analysis says intensive agriculture is the main driver of the declines, particularly the heavy use of pesticides. Urbanisation and climate change are also significant factors.
“The main cause of the decline is agricultural intensification,” said Francisco Sánchez-Bayo, at the University of Sydney. “That means the elimination of all trees and shrubs that normally surround the fields, so there are plain, bare fields that are treated with synthetic fertilisers and pesticides.”
He thinks new classes of insecticides introduced in the last 20 years, including neonicotinoids and fipronil, have been particularly damaging as they are used routinely and persist in the environment. “They sterilise the soil, killing all the grubs.” This has effects even in nature reserves nearby. The 75% insect losses in Germany, for example, were in protected areas.
“If insect species losses cannot be halted, this will have catastrophic consequences for both the planet’s ecosystems and for the survival of mankind,” he said.
This is of course very worrying news, which led me to investigate further to see if anything could be done about it.
It can. The world must eradicate pesticide use, prioritise nature-based farming methods and urgently reduce water, light and noise pollution to save plummeting insect populations, according to a new “roadmap to insect recovery” compiled by experts and published in the Nature Ecology and Evolution journal.
Phasing out synthetic pesticides and fertilisers used in industrial farming and aggressive greenhouse gas emission reductions are among a series of urgent “no-regret” solutions to reverse what conservationists have called the ‘unnoticed insect apocalypse’ as the researchers put it.
Alongside these measures, scientists must urgently establish which herbivores, detritivores, parasitoids, predators and pollinators are priority species for conservation.
Of course, until the world listens to the scientific research and decides to act on it nothing will happen. The failure of much of the world to listen and act on the science of human-made climate change unfortunately doesn’t fill me with confidence that it will act on this new research.