Last year Sally and I happened to be at our cottage, in northwest Michigan, on a spring weekend when frogs and toads were calling. The sound coming from the swamp at night was amazing—like a tremendous frog engine. (It was quite beautiful, as well—especially the sound that I learned later was the call of the American Toad, a long, high trill, bright and ethereal.)
Trying to learn more about what we heard, I went to the internet and discovered the Michigan Frog and Toad Survey, a project of data collection that began twenty years ago in response to worldwide amphibian decline. This year I decided to participate. I set up a route and registered it with the DNR, and they sent me a packet (including recordings on a CD). We studied the calls a bit, then, outfitted with a clipboard and headlamps (and a recording app, on my phone) we headed out on the “early spring” run.
Stop 1: We visited this new-ish park last winter, and discovered there are ponds here. But a walk down the paved path soon after sunset, then off to the right onto gravel reveals no frog sound—just loud, incessant highway noise. Is it I-75, or M-59? Probably both, we think. We hike back up the hill and encounter someone strolling with two dogs, off-leash (one runs up and licks Sally’s hand), and as we get back in the car we hear a rowdy series of whoops from somewhere down below. Quite the party scene, I comment to Sally as we pull out of the parking lot.
Stop 2: It’s almost full dark as we turn in the driveway for the conservation land next door to City Hall. There’s a short flight of stairs down from the lot, and we can see just enough to manage them without switching on our headlamps. A small footbridge crosses a stream and leads to a clear, dry spot surrounded by vegetation. We stand quietly in the dark, hearing nothing. Coming up empty again! Then Sally says, “look” and points, and I see a low, dark shape with a white blaze on its head, coming towards us. A skunk–not hurrying, but purposeful, going about its business. It’s headed right for us, completely unaware of our presence until our voices (“is that a skumk?” “wow”) startle it and we see its tail go up. “Back away slowly” Sally advises, and we do, retreating to the bridge. The skunk disappears into the night. I’m reminded that all kinds of creatures are up and about, in the dark.
Stop 3: Frogs! I was pretty sure they would be here, alongside the Clinton River Trail. We can hear them from the parking lot, and they get louder as we leave the sidewalk for the trail: the steady cheep, cheep of spring peepers. I get out my phone to make a recording, and we try to judge the quantity of the overlapping calls: is this a level 2, or 3? We can replay it later.
Farther along the trail, the bank on one side falls away to darkness and the sound is clearer here. I make another recording, and jot some notes about where we are standing, beside a brand-new trail sign, bathed in light from the skating rink atop the hill behind us. I feel the presence of people in that light, leaking out the windows and strewn across the path—but it seems distant, removed; and the life of the river—which we’ve walked along many, many times now—feels stronger, more connected to me as the frogs go on singing. I stand in the dark just beyond the squares of electric light, and listen.
Stop 4: Holland Ponds: we’ve got the windows down as we drive up and we can hear frogs singing even before we pull into the parking area. Traffic’s not so loud here even though we’re right on the road, and the front ponds just beyond the parking spaces sound like they’re full of frogs. We walk just a few yards down the trail and I get my phone out again to record, but we know this is level 3: a full chorus of spring peepers, a constant wash of sound.
We stand for a few minutes, taking it in. Even in the dark we can see that a lot of brush and small trees have been cut and cleared away since the last time we visited, a year or two ago. Then I remember that while I was on the web creating my survey route I saw some long posts from someone upset about habitat destruction here. Why do people have to mess with things, we ask each other as we get back in the car. There is a great blue heron rookery here; we’ve come in the past to watch the birds sitting on the nests and feeding their young. I hope their nursery survives.
Stop 5: We come in through the “back door” of this park, an unlighted entrance with a parking area just outside the gate. We’ve been here many times too, and we know there are vernal pools below us, at the foot of the hill. We walk along the grass beside the parking lot inside the gate; the dark outline of the picnic shelter looms up ahead. It’s quieter here, away from traffic, and this time we hear several different calls: the clucking of wood frogs—I read in The Sixth Extinction that they are the only frog that lives above the Arctic Circle; they survive the winter by literally freezing (except for their cells, which contain a kind of antifreeze), then thawing out again in the spring.
We can hear chorus frogs, too—a call we’ve just learned to identify from the CD, where the pleasant-voiced announcer describes it as resembling “the sound produced by running a fingernail across the teeth of a high-quality, fine-toothed comb.” The call does sound just like a comb (of what quality, I can’t say I can distinguish) being scraped, so we recognize it easily.
And there are spring peepers going in the background. I record our data and we head back to the car, still not using our headlamps. We can see pretty well, and Sally wonders if there is a full moon tonight, somewhere behind the clouds. Scanning the sky I can’t see any bright spot, and we decide that all of this ambient light is city incandescence—streetlights, houses, shopping centers. Skating rinks.
Stop 6: At this park, we get busted. We’re standing just beyond the parking lot, by the bathrooms, listening to the same trio of species: peepers, wood frogs and chorus frogs, calling from the vernal pools alongside the playing fields when we see a car pull in and circle around. A moment later we see a police car come in behind it.
We’re already back in our car and heading out when the police car pulls up fast, facing us and shining a spotlight straight in. I lower my window and explain we’re doing the Michigan Frog Survey; I hand the policeman our windshield decal as evidence. He is not impressed. You can’t be in the park after hours, he shouts at us, then (still at the top of his lungs) have a nice night. We follow him out, frog-stalking miscreants properly chastened. Next time wear dark pants, Sally suggests, referring to my tan-colored jeans. Rules are funny things, I reflect later. The cop was right, we’re not supposed to be in the park so late–unless of course there is a baseball game being played, then the curfew goes to 11:30. Seems to me frogs are at least as fundamentally American (and worthy of respect) as baseball. They’ve definitely been around longer—like, before there were dinosaurs. Some 250 million years.
Stop 7: This is a spot I drive by on my way to work, closer in to the city. We pull into the driveway of a big, new church, our windows down, and right there where I saw standing water around the trees we hear a chorus frog.
I park the car at the perimeter of the lot and we walk back over to the edge of the trees; stand for a bit, walk up and down, stand some more. Even after listening for a while we think all we hear is that one voice: one lonely little chorus frog, singing away. We turn back towards the car, and for a moment look out over what has to be three or four acres of fresh-looking blacktop, awash in fluorescent light. “All of this must have been wetland,” Sally muses. We get back in the car.
Stops 8, 9, and 10—a couple of retaining ponds, and the gated entrance to another park—are washouts. A fine drizzle is starting as I record conditions and we wrap up: 10:30, we’ve been at it for well over two hours. Back home I’m tired, but satisfied. We found some frogs—I knew we would. I hope that as the woman on the CD says, we’re “contributing to knowledge of the frogs of the world.”
Frogs of the world. I really, really like that phrase.
For more information:
The Sixth Extinction, by Elizabeth Kolbert. If you don’t have time for the (Pulitzer-winning) book, try this article:
The DNR webpage for the Michigan Frog and Toad Survey:
Amphibiaweb (info on worldwide decline of amphibians):