
Like it or not, we can’t live without insects
When insects are killed or die off, everything in the food web is affected, from the birds, bats and lizards that feed on insects to the snakes, coyotes and cougars that feed on birds and lizards, and on and on. (Photo: Karin Lewis via Flickr)
Many people find insects annoying, even frightening. As a former fruit fly geneticist who spent many boyhood years exploring insect and other life in the swamps near my home in Leamington, Ontario, I’ve always been fascinated by them. They’re also a critical component in the web of life.
When insects are killed or die off, everything in the food web is affected, from the birds, bats and lizards that feed on insects to the snakes, coyotes and cougars that feed on birds and lizards, and on and on.
We haven’t learned our lesson over the 63 years since Rachel Carson’s seminal Silent Spring was published — a book that influenced me and others and was the inspiration for growing environmental awareness. Carson pointed out the folly of applying new technologies or scientific developments on a widespread scale without understanding or even considering the impacts on interconnected natural systems.
Insecticide bans helped insect populations recover in some places, but they now face another dire threat: global heating.
Before Carson’s book, Swiss chemist Paul Mueller developed the pesticide DDT and won a Nobel Prize for his work. It was seen as a miracle chemical, deadly to many “pests” and disease-carrying insects. It’s use on malaria-carrying mosquitoes saved many human lives, but it also led to the deaths of millions of bald eagles, osprey, pelicans and other birds. Carson learned that, beyond having a direct impact on animals that feed on insects, especially birds, DDT was also “bioaccumulating” in some species and “biomagnifying” through the food web, including to humans.
Insecticide bans helped insect populations recover in some places, but they now face another dire threat: global heating. Many scientists believe insect biomass is being reduced by as much as 2.5 per cent a year. That may not seem like a lot. “But if you run that forward just four decades, we’re talking about nearly half the tree of life disappearing in one human lifetime. That is absolutely catastrophic,” entomologist David Wagner told the Guardian.
Pesticides (still), habitat loss, industrial activity, agriculture, and air, land, water and light pollution are still eradicating insects, but new research points to climate disruption as an increasingly devastating factor. Insect populations are now plummeting even in areas free from pesticides, fertilizers and industrial activity — including protected forests in countries such as Costa Rica. Many insects are hypersensitive to environmental changes — in heat, humidity, rainfall, light and seasonal variations. Events such as an unusually dry spring can prevent them from emerging from the ground, for example. Availability of water is especially critical, as they must stay constantly hydrated.
We fail to understand that nature, which includes us, is interdependent, that every disruption or disturbance we create will have far-reaching consequences.
Insect collapse is already working its way through the web of life. A 2019 study found that three billion birds in the U.S., close to one-third, had disappeared since the 1970s, mostly those that feed on insects. A 2018 study in Puerto Rico’s Luquillo rainforest found a significant decrease in birds, frogs and lizards as insect numbers dropped.
Because many insects are pollinators, their decline can also reduce plant and food crop growth.
Anyone who’s been around for a while might remember road trips of the past, when you’d have to stop regularly to clean dead bugs off the car windshield and grill. Now, their numbers have diminished to the point that you can often drive a long way without a single splatter.
It’s hubris. We fail to understand that nature, which includes us, is interdependent, that every disruption or disturbance we create will have far-reaching consequences. And so we spray poisons indiscriminately, wastefully burn fossil fuels and destroy natural spaces and habitat. But if insects die, birds and fish that eat them will die and animals that eat the birds and fish will also die…
We must do everything we can to protect insects.
We have numerous solutions to these problems — to climate change, biodiversity loss (including insects) and pollution — but sometimes it means putting life before profit, and that doesn’t sit well with those who make their money from polluting fuels and chemicals.
We must do everything we can to protect insects. That includes addressing climate disruption by shifting to clean energy and conserving and restoring green spaces. Individually, we can grow more gardens with native, pollinator-friendly plants, reduce pesticide and fertilizer use and more.
It’s time to show our insect friends some respect. Our lives depend on them in more ways than most people know.
David Suzuki
David Suzuki, Co-Founder of the David Suzuki Foundation, is an award-winning scientist, environmentalist and broadcaster. David is renowned for his radio and television programs that explain the complexities of the natural sciences in a compelling, easily understood way.
Education
As a geneticist. David graduated from Amherst College (Massachusetts) in 1958 with an Honours BA in Biology, followed by a Ph.D. in Zoology from the University of Chicago in 1961. He held a research associateship in the Biology Division of Tennessee’s Oak Ridge National Lab (1961 – 62), was an Assistant Professor in Genetics at the University of Alberta (1962 – 63), and since then has been a faculty member of the University of British Columbia. He is now Professor Emeritus at UBC.
Awards
In 1972, he was awarded the E.W.R. Steacie Memorial Fellowship for the outstanding research scientist in Canada under the age of 35 and held it for three years. He has won numerous academic awards and holds 25 honourary degrees in Canada, the U.S. and Australia. He was elected to the Royal Society of Canada and is a Companion of the Order of Canada. Dr. Suzuki has written 52 books, including 19 for children. His 1976 textbook An Introduction to Genetic Analysis(with A.J.F. Griffiths), remains the most widely used genetics text book in the U.S.and has been translated into Italian, Spanish, Greek, Indonesian, Arabic, French and German.
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