On a rainy spring morning in Strafford, Steve Faccio stood thigh-deep in water, holding what looked like four globes of translucent white jelly speckled with black seeds. Around him, a small group of nature lovers craned to catch a closer look. Each mass enclosed hundreds of salamander eggs.
“Welcome to the alien party,” murmured one of the attendees.
Faccio is a conservation biologist at the Norwich-based Vermont Center for Ecostudies and an expert on vernal pools, the seasonal wetlands that are a breeding ground for salamanders, frogs, insects and freshwater crustaceans. He oversees a number of active research projects but occasionally plays tour guide to anyone game to get up close and personal with nature. On this day, he was leading eight participants ranging in age from late twenties to seventies on a tour of several pools on a neighbor’s property.
During the two months or more that vernal pools exist, they incubate a staggering amount of life.
Blair Butterfield, a communications director and entrepreneur who recently moved to White River Junction from Florida, said she signed up to gain a deeper sense of place.
“I think I wanted a tactile, engaging way … to be connected with nature,” she said.
Elisa Vesely, a clinical microbiologist from Enfield, N.H., was looking for a stronger connection between her scientific work at Dartmouth College and the natural world.
“Something about the seasonality of vernal pools got me really excited,” she said. “I had to get out of the lab and into something a little bit more outside.”
Also known as ephemeral pools, vernal pools are short-lived but critical natural communities — biodiversity hot spots that explode with life each spring before drying up entirely by summer. (Some pools return in the fall, while others remain dry all winter.)
On average, 70 to 80 percent of the creatures hatched in vernal pools die before the water is gone. But all is not lost. While many lives nurtured in the pools are fleeting, their impact reverberates across the forest food chain. The habitat is a keystone ecosystem, according to Faccio, because of its outsize impact on the overall health of the forest. During the two months or more that pools exist, they incubate a staggering amount of life.
For instance, the “alien” eggs Faccio held in his hands will grow up to be spotted salamanders. The eggs can be identified, he told the group, by their shape, spacing and the firmness of the jelly that held them fast to a twig stuck in the decaying leaves of the pool.
The group also examined loose, shifting masses of chlorophyll-green wood frog eggs nearly ready to hatch, as well as a Tupperware container of water fished from the pool that was teeming with mosquito larvae, water fleas and elegant fairy shrimp.
“I think of [fairy shrimp] as the Cheez-Its of the forest. Everybody loves them, and nobody can eat just one.” Steve Faccio
Given the right conditions, the tiny shrimp can emerge by the thousands in just one small pool. The ones Faccio caught were less than half an inch long and a brilliant orange color, waving their legs hypnotically as they backstroked across their temporary enclosure. In a vernal pool, their beauty goes unrewarded — or, if you’re feeling charitable, they live on in the many lives they sustain. In other words: They’re lunch.
“I think of [fairy shrimp] as the Cheez-Its of the forest,” Faccio said. “Everybody loves them, and nobody can eat just one.”
The group chuckled and continued, undeterred by the steady but not unpleasant rain. Faccio described how life in the pools begins when snowmelt and rain collect in deep depressions in the forest floor. Bacteria, algae and fungi grow like grayish-green fuzz on the leaf litter in the water. They provide nutrient-rich meals to many species of tadpoles and invertebrates such as fairy shrimp, as well as hundreds of insect species that lay their eggs here: caddis flies, mayflies, phantom midges and several species of mosquitoes.
“Beetles, as well,” added Faccio. “Some of them are quite big … and are serious predators. They can even give you a pretty good nip on your finger.”
From there, the pool scene gets pretty steamy — literally and figuratively. On the year’s first warm, rainy night, male salamanders emerge from underground refuges below the frost line, looking for love.
“The males often arrive first, and they sort of congregate up in these groups that are called a congress … probably because they do nothing,” Faccio said wryly, eliciting laughter from the group. “They just hang out and wait for the females.”
Once the females arrive, the males engage in an elaborate courtship dance called liebesspiel, a German word that translates as “love play.” A female will select the male she wants and usually move away from the congress, picking up a capsule of sperm emitted by the male and using it to fertilize her eggs.
As the group explored the pools, Faccio shared some fascinating facts about two species commonly found in Vermont’s vernal pools: Jefferson salamanders and blue-spotted salamanders. Many are clones born from females that need sperm to activate their eggs but whose genome comes solely from their mother.
“Typically, they all look exactly alike,” Faccio said.
And then there are wood frogs, amphibians that freeze as solid as rocks in the winter months, thanks to a simple sugar that courses through their bloodstream, acting as antifreeze to protect their organs. Once the weather warms, they thaw in about 24 hours — and can freeze and thaw again several times before the weather warms consistently.
Fairy shrimp, meanwhile, reproduce young as minuscule cysts that can survive for decades until conditions are right, even after being digested and discharged in duck scat.
The intricate web of life continues from there. Since vernal pools lack an inlet or outlet, no fish can devour the egg masses. But as the amphibians call for mates, they ring the dinner bell for larger predators, such as snakes, small mammals and birds of prey.
Amphibians do not breed exclusively in vernal pools, though species such as the Jefferson salamander are quite dependent on them.
“If we didn’t have all these vernal pools, we’d lose most of their populations,” Faccio said.
It’s a sobering thought in the face of development pressure and the unknown effects of climate change on the pools, which scientists have only recently begun to study.
In 2018, Faccio launched the Vermont Vernal Pool Monitoring Project, which has since kept tabs on 91 pools across the state.
Jock Harvey, a forester from Andover, said the group tour helped him better understand how to avoid disturbing these sensitive habitats with a skidder or a bulldozer, as well as how to share that understanding with others.
“I have to know everything I can about all our natural communities,” he said. “I mean, they’re all interconnected. They’re one great big family.”
The growing interest in vernal pools may also have to do with the way they embody the larger paradoxes of existence: fleeting yet cyclical; fragile but enduring; a grand tableau of life and death that unfolds in the space of a couple of months, in what amounts to a large puddle fed solely by surface runoff. In the era of climate change, vernal pools speak to the bounty of the natural world — and what could be lost.
Butterfield mused that learning about vernal pools and other habitats should be integrated into our education “so that we don’t feel so distant and disconnected from nature.”
“That kind of gap seems to be fueling apathy [about] the climate crisis,” she said. “The feeling [that] we’re bystanders to something that’s happening to the place which we are born into, and should have a deep love for.”
The original print version of this article was headlined “Pool Party | Seasonal wetlands are short-lived but critical biodiversity hot spots”
This article appears in May 10-16, 2023.
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