Field Notes—

Midnight Rendezvous With Yellow Spotted Salamanders

By Dottie Evans

It was a dark and stormy night on Friday, April 7, when I finally saw my first yellow spotted salamander swimming out from beneath the mud-covered leaves of a vernal pool deep in the woods of darkest Redding.

But it didn’t have to be Redding.

My first ever encounter with Ambystoma maculatum might just as well have happened in Newtown, or in any other New England town where woodland pools are protected from development and reappear every spring when the snow melts. These pools provide irreplaceable safe havens for many species of amphibians during spring breeding season.

For the secretive salamanders, timing is all and there is nothing random about this rendezvous. Salamanders do not simply wander through the forest, hoping to bump into mates. Instead, breeding must take place in vernal pools and after mass migrations begun in response to ancient cues embedded somewhere deep down in those tiny amphibian brains.

The narrow window of opportunity opens only once a year, when they exit their solitary burrows. Coming from all points of the compass, they travel overland until they converge at the one vernal pool where they were hatched. Finding other salamanders already there, they enter into communal courtship, and deposit sperm or lay eggs. Within a short week, they leave the pool and go back to their lairs under stumps or inside rotting logs.

It happens only in early spring — usually during the last week of March or the first week in April — only at night when predators are less likely to see them, only when the temperature hovers around 50 degrees, and only when there is rain falling.

The presence of rain is critical because, like frogs, salamanders breathe air but also respire through moist skins that are adapted for the exchange of oxygen and carbon dioxide. Only if they are protected by a steady downpour do the salamanders dare to begin this arduous journey.

Scurry across the forest floor. Scramble through brambles. Tumble over rocks and cross dangerous roads. Slither under fences. Bump against obstacles like stone walls and, if they are lucky, maybe find a way round.

For the species to survive, they must reach the vernal pools where there are no fish to eat the precious eggs, 125 of which are laid in each gelatinous cloud attached to underwater sticks or branches.

The males arrive first. While swimming around together and showing off their yellow spots, they are stimulated to release clusters of sperm called spermatophores. Then come the females, who join in the dance while gathering spermatophores into their genital openings. Suddenly, the vernal pool is roiling with intertwined salamanders, and perpetuation of the species is underway.

It is said that yellow spotted salamanders can live up to 20 years. They are carnivores, and they don’t store food. But they will eat worms, insects, snails, and sometimes small mice. Fossil evidence tells us their amphibian ancestors have slithered, swum, or hauled themselves into and out of watery environments for much, much longer than humans have walked the earth.

Evolution aside, being able last Friday to look closely at one individual was a thrill. Under the glow of a flashlight beam, our salamander, snatched briefly from the water, stayed quiet long enough for us to examine it closely after we gently placed it on a nearby rock.

I was surprised at how sturdy and strong its body was despite two pairs of improbably wobbly-looking legs supported by translucent, splayed toes. I had to admire those jaunty yellow spots arranged in two irregular rows from head to tail. Clearly, no camouflage was intended. Its bold markings seemed to say, “Here I am,” “See my beautiful spots,” and “What took you so long to get here?”

Meeting up with breeding salamanders is not easily accomplished. It takes networking — calling a friend who knows a friend who knows about a certain vernal pool where salamanders gather. Equipment and preparation are key. A salamander seeker needs warm clothes, waterproof boots, a strong flashlight, spare batteries, a net, a camera, and a thermos of coffee for the ride home at 1 am.

Cellphone numbers and emails must be exchanged ahead of time. Plans to be out of town are put on hold. As the end of March approaches, watch the Weather Channel and keep your evenings free.

If the rain begins falling and the temperature begins rising, you figure it’s time. A brief phone conversation and you’re out the door by 9 pm, driving down tree-lined back roads through a dark and stormy night — hoping to crash the salamanders’ yearly coming out party.

For those of us who go in for this sort of thing, it’s a migration of a different kind.

See you next year, down at the vernal pool.