Come early spring at damp, leaf-covered spots in the Southern mountains, the salamander mating rituals can be spectacular.
Casey Phillips/Tennessee Aquarium
A spotted salamander makes its way over mossy rocks.
A few years ago, aquatic conservation biologist Josh Ennen was doing a show-and-tell at his son’s day care center when a child on the front row pointed to the salamander poster Ennen had brought to class and exclaimed, “Look at all those lizards!”
“Those aren’t lizards,” Ennen’s son proudly corrected. “Those are salamanders.”
Many adults too, are unaware of the distinction between the two critters—one is a reptile, the other, an amphibian—much less the fact that, unlike many animals, some salamanders choose winter or very early spring as their time to breed.
“There are a lot of different hypotheses out there about why,” says Ennen, a researcher at the Tennessee Aquarium Conservation Institute in Chattanooga. “But the wet part of the year is really important for amphibians in general.”
What is widely known among aquatic experts is that salamanders rely on vernal pools, also called ephemeral ponds, that fill with water during fall and winter rains. Because these habitats are temporary—they tend to dry up in late spring and summer—they can’t sustain permanent populations of fish that like to feed on salamander offspring. In addition, many mammal predators are still hibernating in February and early March, or aren’t yet very active, which makes it the perfect time for Blue Ridge salamanders like the spotted, mole and marbled species to lay eggs and increase the chance of survival for the young ones to hatch and grow.
Casey Phillips/Tennessee Aquarium
Masses of salamander eggs are found in vernal pools.
And, Ennen says, “Many of the pond-breeding salamanders’ larvae will actually consume other salamander larvae. So by being the first to arrive, you might get a salamander snack later in the spring.”
What happens during courtship fascinates scientists like Ennen. Each year, the salamanders head en masse to the same vernal pools, most of which are located in heavily forested areas with a lot of moist leaf litter. There, they mate and attach their eggs to sticks immersed in the water. “Just imagine hundreds, if not thousands, of spotted salamanders under the water courting each other,” Ennen says.
These woodland spots are actually “some of the coolest places to visit with children in school groups because there are hundreds, if not thousands, of animals coming in within a two-week period,” he says. “It’s a very cool and unique ecosystem.”
Last February, Ennen and his colleague Dr. Jon Davenport began analyzing how spotted, mole and marbled salamanders use vernal pools in Prentice Cooper State Forest, a wildlife management area on the Cumberland Plateau. From his office window, Ennen can see the site, a 45-minute car ride away.
On a gray late-winter morning, the biologists checked minnow traps placed in ponds in the forest. Before long, a row of plastic tubs on the shore was overflowing with dozens of salamanders, some still swollen with unlaid eggs. According to Ennen, his team probably found 1,000 spotted and mole salamanders that day. He notes that the study is still in its infancy but is expected to become more fine-tuned after a few more years of sampling.
The Appalachian region, with its temperate, wet climate, provides the perfect habitat for salamanders.
Casey Phillips/Tennessee Aquarium
Dr. Josh Ennen scouts salamander territory with Southeast Missouri State University researchers.
“The hot spot is right in the core of the Southeast,” Ennen says. “There are more species of salamanders in east Tennessee and western North Carolina than most countries combined.”
Because they are so sensitive to environmental changes, these amphibians are also important indicators of the health of their surroundings.
“I try to instill in my children, and to people that I meet, that there’s nowhere else on the planet that you can walk out and be in a spot where you have so much biodiversity richness in freshwater [species],” Ennen says. “If they go away, that basically means there’s something wrong with fresh water. And there’s no civilization on the planet that can last without good fresh water.”
Want More?
The story above appears in our March/April 2019 issue. For more like it, subscribe today or log in to the digital edition with your active digital subscription.