Yesterday afternoon I got an email from Mount Auburn Cemetery, where I volunteer. “It’s the first warm and rainy day of spring. The salamanders in our vernal pool might be having their Big Night tonight. Come at 7:30 and we’ll go see.”
What? Salamander Big Night? Vernal pool?
Start with vernal pools. “Vernal” means spring, and a vernal pool is a temporary body of water that’s usually formed by snow melt and rain in the spring; often it dries up completely by early summer. Vernal pools have no outlets or inlets, and because they often dry up, there are no fish in them.
But in order to be classified as a vernal pool, the water must have at least one of six so-called obligate species: fairy shrimp (a cute tiny pink-orange crustacean with eleven pairs of legs), wood frogs (with black masks and a quacking croak), or any of four kinds of salamanders.
Mount Auburn’s vernal pool (at the bottom of Consecration Dell) has only one of the obligate species: spotted salamanders.
So they have a Big Night?? Get down and party, do they? Well, in a way. The salamanders have spent the winter in hibernation in leaf litter or other protected places near the location of the vernal pool. On the first spring night when there is rain, the temperature is above 40, and the ground has thawed, they begin to emerge and head toward the pool. Males and females cavort in the pool in a congress; males deposit packets of sperm which end up on the bottom. Lots of them. A female chooses one in some mysterious fashion, picks it up with her cloaca (the opening to her reproductive tract), and fertilization takes place within her. Eggs, in a gelatinous mass, result a few days later.
Back to Mount Auburn Cemetery’s Big Night, about which I got the email.
A little crowd of salamander hunters was gathered at the front gate in the dusk. By that time it had not been raining for quite a few hours, and I was worried that the salamanders would not find the weather to their liking. I liked it though—warmish and humid after a long, cold, windy winter. I took some pictures of the bare trees against the sky, which was gray and overcast. We made our way to Consecration Dell and the vernal pool in the bottom of it.
The pool still had a pancake of ice in the middle, though the margins were clear. I wondered about the fox I have seen on occasion round about. Did he ever come and drink from the pool?
We were met at the pool by Joe Martinez, a herpetologist (a person who studies reptiles and amphibians). Joe has been studying the herptiles at the Cemetery for quite a while. He had some equipment with him—a few nets and some plastic tubs—and he’d already captured a fine large painted turtle, whom we all admired.
As darkness gathered, we went slowly around the pool with our flashlights, shining them into the water to see if we could spot any salamanders. At the edges, where we could see in clearly, there was lots of leaf litter on the bottom. This is good because as these leaves decay they provide food for some very teeny tiny organisms, which are of course in turn eaten by somewhat larger creatures, and so on up to the larvae of our spotted salamanders, which feed on pretty much whatever they can find.
I myself did not see any salamanders on my circumambulation of the pool, but I loved being in the dark, moist air. I began to hear the loud, high-pitched chirpings of spring peepers. That’s a very small frog, I mean really small, one to one and a half inches long. How can he make such a big sound?
“Look! Here’s one!” I heard from the other side of the pool. I hurried over. Not a salamander, but a spring peeper. Flashlights shone on the leaves. For the life of me I couldn’t see anything. “No—right THERE!” Oh! My goodness, he looks just like a leaf. He sat in our lights, frozen. I took some pictures. We began to hear them all over. Their chirps are astoundingly loud, especially when you see how tiny they are.
Joe called, “I got a toad!” We gathered around him to see. Several years ago he released some American Toads near the pool, and he has been monitoring their progress, inviting visitors to report sightings, which he marks on a map of the Cemetery. The map shows how their population has increased and is moving through their new home.
Grasping the 2-inch toad by his hinders, Joe shows him off. On his toadly shoulders he has a pair of parotoid glands, raised, smooth bumps which contain an alkaloid poison, not too harmful to humans but a neurotoxin to anything that tries to eat him.
The turtle and the spring peepers and the toad are all great and we are happy to see them and take their pictures. But where are the spotted salamanders?
I set off again round the pool with my flashlight illuminating the now-dark path and the shallow water. As I come round to the beginning again, there’s a commotion. “Got one! Got one! I’ll put him in the tub!”
Yes indeed, there in the bottom of one of the plastic tubs is a handsome spotted salamander, black with yellow spots. We watch him and, possibly, he watches us. Joe explains that the spot pattern is unique to each animal, and he has a portfolio of the Consecration Dell spotteds. He says he has had repeat sightings several times. Somebody asks about their lifespan, and we learn to our surprise that it can be as much as twenty years.
Joe angles to get a good picture-taking view of his catch. You have to place your flashlight’s light just right to get a good picture. After Joe is done, I photograph too. I love the salamander’s big eyes, an inscrutable matte black. I chirrup at him, “Good boy! [He is a male.] Look at your pretty spots! Look at your nice tail and your little fingers and toes!”
But no females are to be found in or around the pool, and after a little while longer admiring our one animal, most of us head back to the front gate. Today I learned that Joe had located several more spotteds after we left.
But still not the really BIG NIGHT. Perhaps not wet enough. It is supposed to rain in the evening later this week. Maybe we will go out again. I hope so.
So many great dramas of the natural world take place right around us, but are hidden in plain view. More’s the pity. Here’s reality, not virtual but REAL. But you gotta look or you won’t see.