The Urban Pantheist

If you visit a Mass Audubon Wildlife Sanctuary at certain times of year, you are likely to encounter these small exclosures.


If you are lucky, you might encounter a small group of naturalists carefully digging out, marking, and relocating turtle eggs. They mark the eggs to make sure they are relocated in precisely the same orientation they were in previously.


If you are remarkably fortunate, you will encounter a diamondback terrapin in the act of laying her eggs in a hole she dug in the sand. This species is listed as Threatened in Massachusetts, in part because of their very particular habitat needs. They are neither pond nor sea turtles, rather they require the brackish water of our relatively scarce salt marshes.


A hundred years ago this species was nearly wiped out due to being collected as a food animal. Every nest counts toward bringing it back to a stable population.

The most massive reptile in New England is the common snapping turtle, Chelydra serpentina*. I thought these ladies (engaged in tandem egg-laying, a behavior I'd never seen before) were rather petite, at about a 12 inch shell length and probably weighing under 10 pounds. Big ones achieve an 18 inch shell length, and weigh up to 35 pounds. Probably there are monstrous individuals twice that size, in overfed captive collections, and the primordial past.

Snappers are entirely aquatic, swimming well but often spending hours inactive waiting for food to drift by. They'll eat any animal small enough to fit in their mouths, including, reportedly (put probably very rarely) baby ducks. Plants make up about 40% of their food--despite their reputations they are less predatory than their tiny cousins the spotted turtles. I've been looking for verifiable stories of humans being bitten by snappers in the water, and have come up dry.

They'll only come up on to land to move to better water--or if female, to lay eggs. That's when most of us encounter them, and when most humans get bit. Can you blame them, though? Their shell is skimpy, leaving lots of naked underbelly, and on land they are on the vital mission of creating the next generation. I'd bite you too.



* "Snake-like turtle" because their necks are long and their faces are bitey.

In April the snakes around Boston wake up and get right to business! Here are two or three common garter snakes Thamnophis sirtalis in a mating cluster along the fence between our yard and driveway. Once discovered they scattered, and I picked one up for posterity.


The saliva of garter snakes is toxic, a form of primitive venom that help incapacitate their prey of earthworms, amphibians, and small mammals. The worst it can do to a human is make us a little itchy. This snake didn't bother, and also didn't make use of its more effective defense, emptying the contents of its cloaca--complete with a powerful scent marking musk. That smell may help snakes communicate with their kind, but on human skin it just communicates a need to wash your hands repeatedly to get rid of the clinging stench.


Garter snakes are gentle creatures, easy prey for cats, dogs, turkeys, and crows in the suburbs. It's possible that their yellow stripes let predators know garters don't taste great--depending on how many toxic amphibians they've eaten. Toad and newt poison can build up in garter snakes, making them one of the few animals that are both poisonous AND venomous.

Soon after we arrived someone asked "have you seen the alligator yet?" Wait, what? Suffice it to say we spent a lot of time looking in the water after that. Then I saw one. Then I saw one every day I was there. Turns out there are a number of small alligators in the lake, they are probably fed by hotel guests, and then they are removed when they get over 4 feet long.


I'd kind of like it if they left them in there to get huge, but that might be kind of dangerous, especially with all the kids running around the place.


The alligators' companions are large soft-shelled turtles--I suspect these are rescue animals given safe haven in the lake.

As it so happens a naturalist friend of mine was also in Florida that week visiting relatives. We live just a few miles from each other but hadn't managed to get together since the April Urban Nature Walk. We were each on opposite sides of South Florida so she suggested we meet up in the middle, at Big Cypress National Preserve. This picture is taken at the Oasis Visitor Center. Theres a wide canal between the road and the building, with a nice boardwalk and fence. Down in the canal there are many many alligators.

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Eastern milk snake Lampropeltis triangulum triangulum

It seems calculated to infuriate me, that on the day before a holiday about a mythical purging of snakes (a symbol for the forced conversion of pagans to Christianity), I should find a dead snake in my yard, killed by a predator that couldn't be bothered to eat it. Eastern milk snakes are purportedly quite common in our area, and yet I've personally only encountered one live one, and this dead one. I took care of a couple captive specimens at Drumlin Farm, fairly calm educational animals that eventually died of gout.

Eastern milk snakes are constrictor snakes that prey on mice and other small animals, including other snakes. Sometimes their orange and brown pattern causes the over-cautious to mistake them for copperheads--a venomous species (which enjoys protected status, so don't go chopping them up with your shovel you big bully). Milk snakes are so-called because they were frequently noticed in dairy barns. Hopefully no one actually believed the ludicrous idea they were feeding on milk, since it should be clear that they were feeding on mice in the barns.

The African dwarf crocodile is the smallest crocodile species in the world and (at 4 feet long for a mature specimen and 6 feet for an exceptional one) among the smallest of the crocodilians. It is a nocturnal aquatic predator that feeds on fish and amphibians in good times and crustaceans and carrion in leaner times. Because it is small and relatively vulnerable to larger predators, it has evolved a armored skin which is thick even among its kind. I can vouch for the difficulty that skilled veterinarians experience trying to tease a hypodermic needle between its scales to obtain a blood sample, as well as the extraordinary efforts required for abdominal surgery.

Depicted is a healthy male, over 30 years old with many years left in him. He is seen here in the Tropical Forest exhibit--he laid "basking" indoors with his mouth agape for at least 20 minutes.

Photo by cottonmanifesto. Location: Leverett Pond, Olmsted Park, Brookline.

Urban species #174: Pond slider Trachemys scripta

In parts of North America other than New England, the most common turtle is often one or another kind of pond slider. There are numerous subspecies with slightly different markings of red or yellow, occurring south and west of New England, and as far south as South America. Sliders are named for the action they perform when they detect humans or are otherwise disturbed: they slide off their basking site into the water. Pond sliders are primarily herbivorous, feeding on aquatic plants like water lilies and duckweed, and only occasionally taking small animal prey.

The red-eared slider is the most well-known subspecies of pond slider, and is found in the Mississippi River and westward, as well as in the pet trade. Unfortunately, pond sliders outgrow the small aquaria that they are usually housed in, growing to be nearly twice as big as their relative, the painted turtle. All too often, these pet turtles are dumped into the local waterways--there are now populations of pond sliders in South Africa, Guam, and several Asian countries. There may be negative impacts on native turtles due to these introductions, but this apparently isn't well studied.

There seems to be a fairly healthy population of pond sliders in one section of the Muddy River in Boston. It isn't clear which subspecies it is, as the markings are indistinct. According to one source, introduced sliders do not breed in New England, but each individual may live 30 to 40 years, and have an effect on the ecology of its adopted home.


Painted turtles on right and left. Pond slider in center. Location: Willow Pond, Boston.

Location: The Riverway, by the obsolete Carlton Street Footbridge.

Urban species #168: Snapping turtle Chelydra serpentina

The largest reptile in New England is also the most common reptile of our urban places. Tolerant of pollution, and able to make use of a variety of different food sources, including aquatic plants and carrion, the snapper seems otherwise unlikely to live in the city. Living up to 40 years and growing to 30 pounds or more, the snapping turtle is viewed by many as a fierce predator. It can be, as it squats in the muck covered with algae, ambushing fish, frogs, and arthropods. The snapper's long neck can extend almost the entire length of its body, and its strong jaws and sharp beak chop prey animals in half. But very often, particularly in urban settings, snapping turtles scavenge the meat of animals that have already perished.

Most city people become aware of snapping turtles when, usually, in the early morning on a bright summer's day, they encounter a snapping turtle on land. These animals are loathe to leave the comfort of the murk, but are compelled to do so when it is time to lay their eggs. Females, laden with eggs that may have been fertilized by sperm that they have stored in their bodies for over a year, haul their bulk onto land and make a perilous journey. The snapping turtle's body is covered by their shell quite incompletely, and much exposed flesh is vulnerable to raccoons, foxes and the like. This is why, on land, a snapping turtle will puff up, hiss, and strike ferociously. They must find a place to lay their eggs in well-drained soil, to ensure that they will not be destroyed by flooding--the eggs must breathe. Sandy soils are preferred--path and road edges, as well as parking lots are favored locations for nests.

Anywhere between a dozen and eighty eggs may be deposited, and the vast majority will are eaten by skunks and other predators. The tiny hatchlings are fodder for herons, other birds, and fish. Only a few make it to adulthood, but when they do, nothing can reliably prey on them. Once grown, an urban snapping turtle's worst enemy is the common automobile.



[I have been asking people at every opportunity--for instance, snapping turtle demonstrations at my work--if they have ever been bitten by a snapping turtle in the water. It is my belief that, while this is a widely feared event, it almost never occurs.]