The Urban Pantheist

When I first encountered salamanders in the swampy seep at the edge of Ward's Pond, I misidentified them as northern dusky salamanders; a fried suggested it might be the leadback phase of the red-backed salamander; then, more recently, it was suggested that this is the two-lined salamander. This picture was taken on an uncommonly warm December 26. I think I'll return to the pond in spring, with my more knowledgable friends, to settle this amphibian mystery.

When is a redback not a redback? My first instinct when I flipped over a board on a muddy boardwalk and revealed this creature was that it was a red-backed salamander Plethodon cinereus*. After all, that's by far the most common tailed amphibian in the woods of New England, especially in woods near humans. But it is missing its nominate field marking, a brick red stripe down its back. It turns out there is a fair amount of variety of coloration throughout the species. This morph is referred to as the "lead back" to rhyme with redback. Our friends at Wikipedia report that members of this color morph are more likely to run from predators, while red-backed redbacks are more likely to dare the predator to remember what red animals taste like. This individual provided anecdotal reinforcement to this idea, as it quickly slithered and jumped(!) when I tried to photograph it.



Thanks to eumorpha-dreaming for the identification help!

* "Many teeth, ash-colored."

Yesterday I found the biggest wine cap I've ever seen. This mushroom is native to Europe but is common in North America but only in man-made environments, especially woodchips. I'm trying to grow a little patch of them in my front yard but nothing so far.


Back at home, this redback climbed up into the dogwater and couldn't get out. I wasn't sure it was alive at first, but when I touched it it tried to wriggle away. Can lungless animals drown? (Yes, I would guess, if immersed in water that was not highly oxygenated enough).


When I removed the cover from our grill, this spider was hunkered down on the propane tank. I pestered it a little to see if I could ID it but it remains unknown. Cool markings on the abdomen, though!

Red-backed salamander Plethodon cinereus

It's been almost ten years since I've photographed a red-backed salamander in the city. There are very few amphibians on my lists of urban species (two frog species and now two salamander species at this point). Amphibians have the challenge of a permeable skin, which exposes them to the various pollutants in the urban environment. They are particularly sensitive to acidic substrates, a condition which has been increasing in their eastern forest habitat for more than a century. In the case of the red-backed salamander, their skin is their only mode of respiration: they are lungless salamanders.

Despite this anatomical obstacle, red-backed salamanders are thought to be the most common amphibian species in the northeast North America. Unlike frogs and many other salamanders, they don't require bodies of water to breed; their offspring are born as miniature adults instead of as gilled larvae. They live in leaf litter, feeding on small invertebrates. Females guard their eggs until they hatch, and relatives recognize one another by scent and tolerate each other within a territory. These tiny animals (three inches long is a very large individual) are thought to live to about 10 years old, and possibly as old as thirty.

This individual was taking shelter in the fronds of a hen-of-the-woods mushroom, on a rainy afternoon in the Riverway.

Photos by cottonmanifesto. Momentarily captured in a hat, to be shown to the members of the Urban Nature Walk group.

Urban species #296: Northern dusky salamander Desmognathus fuscus

Bullfrogs not withstanding, amphibians are not commonly found in urban areas. The reason is their semi-aquatic habits, and their permeable skin. Water and gases can pass through an amphibian's skin, and so if the water or air are polluted, that pollution can enter the animal's bloodstream. Most urban water contains too many metals and other contaminants to support amphibian life. Even those amphibians that live on land lay their eggs in water, or in moist earth, exposing their developing young to environmental poisons. While permeable skin may seem like a complete liability, it has its advantages. Because oxygen and carbon dioxide can pass directly through an amphibian's skin, they have reduced the need for lungs. In a few species, such as the northern dusky salamander, and the exceedingly common redback salamander, the lungs have completely disappeared. The lungless condition is thought to have evolved to reduce buoyancy in stream-dwelling salamanders, and has persisted in several descendant species that live in other habitats.

The small colony of northern dusky salamanders I discovered lives on the margin of Ward's pond in Olmsted Park. Jamaica pond is uphill and upstream from Ward's pond, and water from Jamaica pond seeps through the soil between the ponds. This water, originating in a natural spring, is relatively clean, and very cold. Forested groundwater seeps are the preferred habitat of this species, and it is through the fortuitous creation of Olmsted Park that this population of salamanders survives in the city. They hide under fallen wood, feeding on small invertebrates, writhing when disturbed, with the help of a keeled tail, even taking to the water when pressed. They don't generally enter the pond itself, where they would be quickly preyed upon by turtles and fish.

Brighton is a borough of Boston, west of the city proper, on the Charles. It's a densely populated neighborhood of students and immigrants with at least 3 hospitals, and the sprawling campus of the Boston Archdiocese. I lived there, right of off famous Commonwealth Avenue (known mainly for BU and BC) in the last remaining house on a street with two hospitals, a methadone clinic and an apartment building. We had a small back yard, remnants of the landlord's decades-old garden, that we held pagan rituals in. One day I was cleaning up debris from the yard and found 21 red-backed salamanders (Plethodon cinereus).

( One salamander (big picture) )