Out here on our farm, nestled in the middle of somewhere, on a gravel-sideroad part of Nova Scotia, I was out looking at the night sky, and I realized something.
The fireflies are back, and they’re different.
We are blessed to live where biodiversity is still a thing. We have countless field songbirds, moth species, winged pollinators, various flies, diverse spiders, and on and on. It’s a place of life’s richness and strength. And so I try pay attention to what’s in ascendence, and what is struggling.
Five years ago we had fireflies everywhere at this time of year, pulsing out their mating messages, looking for a hook-up: the females, resting insouciant in the grass or the bushes, flashing come-hithers; the males, flying and flashing out where anyone could see, strutting their sparkle and hoping to strike up a light conversation with an interested babe. It was a lightshow fog of firefly glint, as much as eight to ten feet high.
Then, for about three summers, there were hardly any fireflies. Last year’s weather was crazy — a spring of deluge followed by a summer of drought. The year before that had its own extremes of cold and hot.
I suspect that the firefly larvae struggled, in those weather extremes. I think the populations were down.
This winter had layers that lasted — that is, lots of topsoil had an insulating blanket of ice and snow and ice and snow, which meant that fewer ground-dwelling larvae were freeze-killed.
And they’re back this year for sure. The constellations of glow-stars are ever-changing, and amazing.
This year, the males are flying higher than I’ve ever seen them. Twenty, even thirty-five feet above the ground. Some of them may be even higher. As an evolutionary strategy, it makes sense — the higher the dude’s able to fly, the more babes he can see — but these heights are new.
I asked myself why, and then answered it: it’s possible that I’m seeing sudden-onset evolution at work.
You see, the Little Brown Bats of Nova Scotia have all died, in their hundreds of thousands, over the last few years. A fungal infection called White Nose Syndrome had a fatality rate of 99% for most bats that hibernate in large groups — and that included most of Nova Scotia’s bats. And it’s worth noting that the last 1% are more than likely also dead — bat specialists just don’t want to believe that they’re all gone.
Bats are mostly nocturnal and eat their weight in insects every night or two. Five years ago, We used to see them flying at dusk, swooping and hoovering up the available insects. It’s almost certain that bats prefer insects high up in the air, away from grasses and trees and bushes — just the kind of thing that these firefly dudes are now doing.
One more fact: evolution thinks males are a dime a dozen. Because males of most every species can procreate with more than one female, there’s an evolutionary advantage (at the species level) for male risk-taking. Males, especially mating-age males, are genetically programmed toward risky behavior.
Males of every species are the ones that use risk as a tool to demonstrate reproductive fitness: If I can [drive a motorcycle with my feet/fly higher than every other firefly/find a new microenvironment] and survive, then I’m a winner, and so my genes are promising to the ladies.
For the fireflies, in earlier years, when risk-taking males rose way up high, they’d be the fat & juicy meal for the bats, up in ecolocation heaven.
But the bats are gone. Nobody’s feasting on the high-flying fireflies.
So the high-flying risk-taking firefly males have a smooth, open, straight road to show off their foot-motorcycling skills on. Nothing’s standing in their way, and by flying high (a very risky behavior, previously), the dudes have the best perspective on the babes at the ground-level bar.
I think we’ll see fireflies rising higher, every year for the next many years. Bats only reproduce one at a time, for a handful of years. To regain the numbers that were lost may take a century, if ever.
In the interim, the much-more-rapidly reproducing fireflies will have no evolutionary pressures to not fly as high as they want. Nighttime predators are few.
Already, those flashing bursts they make in the dark sky compete with shooting stars, the celestial dust flaring as it enters Eearth’s atmosphere. I’m not sure which I’m seeing: a burning particle from space, or a firefly?
Is this a good or bad thing for good ol’ Mother Eearth? I don’t know. Bats dying off is clearly bad. Fireflies recovering is good, I think, but I’m ignorant of the whole lifecycle of fireflies (do the larva eat anything I grow to sell?), so it’s hard to say.
Clearly things are out of whack. Ecosystems are changing, and I need to be paying even closer attention to the particulars. It may be easier to see out here where biodiversity is still robust — but urban biodiversity is also being affected.
We are in for a strange time, in the years ahead. It’s trouble for slow-reproducing critters, and for those with specific dependencies (like Monarch butterflies requiring milkweed to lay their eggs).
Climate chaos will lead to micro- and macro-climate disruption. Keystone species (like bats) may die off. Other keystones may be stressed because of it, and the heretofore traditional balances, upended. Nothing much is likely to remain “the way it’s always been.”
The more we can inform each other of these changes, the better. Alas, the corporate-media industries don’t want us to pay close attention, since any change threatens the status quo (which has enriched them tremendously).
Instead, they want us to believe all is well, and that nothing has changed.
The fireflies — whose lightshow is undeniable — beg to differ. Their evolutionary pressures have been dramatically disrupted, and their behavior is changing as a result.
Like the weather extremes we’ve been seeing the last decade, in the seasons ahead we may see species extremes bursting out like fireflies on a dark night.
Human society needs to figure out as much as we can about what’s happening in microclimates worldwide. We need to fund scientists for whom that search is a career. We need more information, because the world is changing radically and rapidly. We need to understand the world we’re deconstructing, so we can slow the environmental disruption we’re creating.