Volume 51, Issue 3: Summer 2017

Tick Talk

Painting by Jan van Kessel (1626–1679)

Human knowledge will be erased from the world’s archives before we possess the last word that a gnat has to say to us.” -Henri Fabre

As an urban dweller temporarily abandoning the city for the verdant charm and calm of the countryside, one of the first things that strikes me — quite literally — is the abundance of bugs. Whether I am shooing flies, trapping ants, swatting mosquitoes, combing my dog for ticks or saving moths from suicide by light bulb, I am surrounded by a plethora of creepy crawlers and frequent fliers. It seems counterintuitive then to learn that their kind may actually be dwindling.

But the cause for concern was driven home, as it were, by reading about the “windshield phenomenon,” a piece of anecdotal evidence prompting some scientists to fear a sharp and generalized decline in insect populations, at least in parts of Europe and North America. Decades ago, you couldn’t drive on the highway in summer without producing a hecatomb on your windshield. Now the carnage is so minor it hardly warrants the wipers. It turns out the vanishing butterflies and endangered honey bees that have winged their way into the headlines in recent years may be the tip of a bigger, largely uncharted iceberg.

Let’s face it: apart from a few other attractive species like dragonflies, ladybugs and those twinkling stars of the beetle order, fireflies, most bugs are beings only an entomologist could love. It’s hard to regret the waning of the parasitic wasp, for instance, the creature Charles Darwin found so ghastly as to controvert any claim of divine design. And the sheer number of bugs is staggering: the first time I saw “quintillion” used to refer to something countable in the real world was in an estimate of how many insects are alive on the planet at any given time. There are, apparently, some 200 million of them to every one of us. That adds perspective to the question “Where have all the insects gone?” (Science magazine, May 10, 2017). Yet if this query is unlikely to be immortalized in song, it should still set off some alarm bells.

In the Science article, Gretchen Vogel reports that data collected from 100 nature reserves across western Europe by members of a German entomological association revealed that the total biomass of insects trapped for research purposes had fallen by nearly 80 per cent between 1989 and 2013. This confi rmed a pattern registered by earlier studies (Christian Schwägerl, “What’s causing the sharp decline in insects, and why it matters,” Yale Environment 360, July 6, 2016). Ecologists are quick to point out that this degree of decline has dramatic implications, beginning with the stability of the food chain, as insects are a crucial source of nutrition for other animals such as birds, amphibians, reptiles and certain mammals.

Insects also play a pivotal role as pollinators and as predators of other insects, which has a major impact on human agriculture. And there’s so much that remains unknown about the complex roles and interactions of various species in sustaining ecosystems. As the 19th-century naturalist John Muir put it, “When we try to pick out anything by itself we find that it is bound fast by a thousand invisible cords that cannot be broken, to everything in the universe.” Darwin’s faith-defying parasitic wasps, for example, whose larvae eat their hosts alive from the inside out, perform crucial pest control functions that protect crops (Seirian Sumner and Ryan Brock, “A world without wasps would be catastrophic for ecosystems and the global economy,” The Independent, July 19, 2016).

While the evolution of automotive aerodynamics has been invoked as one explanation for the windshield phenomenon, the decrease in insect populations is real and measurable and the likely culprits are habitat destruction and degradation as well as the direct and indirect effects of pesticide use.

It stands to reason, too, that insects would be affected by the general extinction crisis, which recent studies indicate is even more severe than previously thought. Looking at the decline of vertebrate populations in addition to the rate of actual species extinctions led one team of scientists, Gerardo Ceballos, Paul R. Ehrlich and Rodolfo Dirzo, to warn of biological annihilation and to contend that we are actually in a mass extinction event, against the more generally held and slightly less grim view that we are edging toward it. It has been suggested that the relative lack of attention paid to the fate of invertebrates may actually be leading the scientific community to underestimate the scale of the problem. What is sadly indisputable, though, is that for the undomesticated nonhuman members of the kingdom Animalia, from charismatic megafauna on down to unendearing invertebrates, time is running out.

Andrea Levy is a Montréal-based historian, translator, journalist and activist, and has been a CD editor for 15 years.