Big Night for Frogs & Salamanders | First Light

By Loree Griffin Burns

Big Night comes when late winter melts into early spring. Here in central Massachusetts, this happens in late March, or sometimes April, as temperatures make their first-of-the-season climb into the 40s and stay there through the night, and the clouds drop rain instead of snow. It has to be warmish and wet. That’s the weather for amphibian migration. That’s Big Night.

Here’s what happens: Rain falls onto pavement, backyards, cars, houses, and also treetops and leaves and the forest floor. This rain calls to the frogs waiting under leaf litter and to salamanders inside the hollows of downed trees. Or maybe it’s the warmth that calls to them. They hear, anyway, and when the sun goes down, they emerge, moving in the direction of whatever small, seasonal pool of water was the place of their birth. That’s where they’ll breed, and that’s why they travel over wet forest floor, through wet rural backyards, down wet driveways, and across wet streets.

The streets are a problem. When roads run between the forests where amphibians spend the winter and the vernal pools they seek in the spring, there will be accidents. Frogs and salamanders will meet cars and trucks. Thankfully, though, there are some humans—the Big Night volunteers—who will stand watch on those very streets. Last year the city of Keene, New Hampshire, closed North Lincoln Street, and in one night volunteers counted 420 wood frogs, 349 spring peepers, three spotted salamanders, and one red-backed salamander … all crossing between 8 and 10:30 p.m. In other places, volunteers have built and maintained tunnels that run under busy thoroughfares. If not for these interventions, it’s likely that half the amphibians migrating across roadways would be crushed.

At my house, we eat an early dinner on Big Night. Then we dig out rain boots and slickers. We dress in layers, test the batteries in our flashlights and headlamps. We pack into the car, giddy, and meet up with friends in a parking lot nearby. There’s a trail at one end of the lot, and it meanders by a vernal pool that hosts migrating wood frogs and peepers and salamanders. The kids gather at the entrance to the trail and wait for the pep talk. They shine their flashlights as far as possible down the path in front of them, desperate for a stirring in the wet leaves. I try to slow them down, remind them that we might not see migrants tonight. The joy is in the looking, I say. The fun is in discovering for ourselves if tonight is really Big Night.

You see, even though the amphibian migration is predictable, it’s not in a way that can be printed onto a calendar. Small differences in the conditions between locations must be considered. It can be raining in our driveway, and not raining at all at our favorite vernal pool. It can be warm enough at home, and much too cool over there; even the friendliest 45-degree afternoon can drop a shocking 10 degrees by the time the sun has fully set. Add to all this the individual personalities of the amphibians—they move when their bodies tell them to move. Some will go a bit earlier than the others, and always there will be stragglers. Migration can happen en masse over several perfect wet, warm nights or spread out over weeks of partly spitting, partly dry, sometimes balmy, sometimes chilly ones. Big Night can be elusive.

Still, it’s a night that stays with you, a weather pattern you can teach yourself to recognize year in and year out. When the right conditions come around again, you listen closely to meteorologists and talk to amphibian-loving friends, and eventually that night arrives when you feed the kids cereal at 5 o’clock and dress them for rain. Even though it’s not for sure yet. Even though it’s a school night. 

Hoods up, pants in our boots, standing at the trailhead, we know we might be here too early, or too late. The kids try to contain their Big Night energy, but can’t. They strobe the woods with their flashlights as we walk, listening for the sounds to celebrate: the quacking call of wood frogs, the shrill pip of spring peepers. In the hierarchy of Big Night thrills, first there is the warm rain, then there is the calling of migrating frogs, and finally, the fondest wish of everyone present, there are amphibians in the flesh and on the move.

“I see one!” someone shouts, and there follows a stampede of humans.

One spotted salamander, frozen in the beams of seven flashlights. He’s five inches long, black and yellow-spotted. His wet skin shines. We squat around him in a circle, get quiet at last.

“He’s perfect,” someone whispers.

All around us, late winter melts into early spring.

How to Have Your Own Big Night

The best way to experience Big Night is to find a vernal pool you can reach by foot. This easy access means you can visit it regularly, upping chances that you’ll spot migrants. (And by not driving, you’ll likely save a few amphibian lives, too.)

Learning more about vernal pools and the spring amphibian migration can be as easy as contacting your local nature center. The Harris Center for Conservation Education in Hancock, New Hampshire, runs volunteer “crossing brigade” programs each year, and its website includes a list of similar programs throughout the Northeast (go to harriscenter.org and search for “other crossing brigades”).

Wildlife tunnels have been an effective solution to the road crossing problem, and several New England communities have installed them, including Monkton, Vermont, and the Massachusetts towns of Amherst and Princeton. In fact, the Hitchcock Center for the Environment in Amherst helped build the first amphibian tunnels in North America, back in 1987; you can read about tunnel operation or volunteer to help with maintenance at hitchcockcenter.org (search for “salamander tunnels”).