Mountains and Marshes. David Rains Wallace
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only remotely green snake here is the racer, which can be olive drab when it’s not plain brown.
Archetypes aren’t everything, however, and the Bay Area may be the snake capital of the West Coast. Species from all over converge on our convenient location and salubrious climate, about equally divided among ones with northern, eastern, and southern affinities. Roughly two dozen species live here, although it’s hard to be sure because snakes are such cryptic, supple creatures. Legless crawlers may seem primitive, but fossils show that snakes are the most recently evolved of major vertebrate groups, appearing about 100 million years ago, after mammals and birds. Evolution often diversifies by simplifying: snakes have traded legs for a versatile niche in the interstices of things. And they can be hard to find there. In five decades of hiking around the Bay Area, I haven’t seen all the species thought to live here.
Only one species is really commonplace, like deer or quail. That is the gopher snake, the medium-sized tan-and-brown-mottled species that stretches lazily across paths even in the Berkeley Hills. It is an easygoing snake when mature, although little ones can be bratty, striking and vibrating their tails at passersby. I suppose one reason gopher snakes are so common and good-natured is that they are well fed: they eat an abundant variety of small mammals, including gophers.
Garter snakes are North America’s most common snakes, but there are so many species that it’s hard to know which you’re seeing. The Bay Area has three, but there are several subspecies and an impossible tangle of common names. Most garter snakes have yellow stripes, but two species here also have other colors. One of these, Thamnophis sirtalis, has red stripes or blotches—and often a blue belly. It is common in terrestrial habitats, although a subspecies, the San Francisco garter snake, is endangered. Another common species, T. elegans, has red stripes or blotches—rarely a blue belly—and lives in similar places. The other Bay Area species, T. atratus, has only yellow stripes and is common in aquatic habitats. The two terrestrial species may frequent water too, however. Garter snake identification is just a mess, although stripe color sometimes helps. Happening once on a garter snake eating tadpoles of the endangered red-legged frog, I knew it wasn’t one endangered species eating another because it had only yellow stripes.
Bay Area garter snakes, at least some of them, have one uncommon talent. Snakes are of course notorious for injecting poison with hypodermic fangs, although most don’t have poison or hypodermic fangs. But garter snakes here are famous for their ability to digest the virulently poisonous bodies of two local salamander species, the California and rough-skinned newts, which can contain enough toxins in their skins to kill multiple humans. Bay Area newts are the most poisonous on the West Coast, and they may have become so in an “arms race” with Bay Area garter snakes.
The Pacific rattlesnake is the only other species I’ve seen here very often. In protected areas like Mount Diablo, rattlesnakes can be almost as visible as gopher snakes, and they have similar lazy dispositions in my experience, although I’ve never deliberately gotten close enough to test this. (Rattlesnake venom seldom kills humans, but an envenomed bite is very painful and may cause lasting damage to tissue.) I’ve accidentally walked within a foot or two of some and gotten no response. I’ve never even provoked a rattle here. The snakes just crawl away. I’ve used a pole to coax rattlers off roads a few times, and they don’t coil or strike, just feint irritably at the pole before departing.
Perhaps Bay Area rattlesnakes are phlegmatic because, like gopher snakes, they have plentiful food sources, especially California ground squirrels. Rattlesnakes live on such close terms with the squirrels—in their tunnels—that adults may be immune to rattlesnake venom, having survived a bite or two. Rattlers mainly eat young squirrels, although adults defend their babies by kicking sand or waving their tails at them. Females rub shed snake’s skins on themselves and their babies, thus confusing the rattlers’ sensory organs.
Maybe some rattlesnakes here have just given up bothering about people because there are so many of us wandering around. Once, unwisely climbing a steep grassy slope off-trail, I came face to face with a rattler in a squirrel hole under a rock overhang, and it didn’t blink (figuratively speaking, that is—snakes don’t have eyelids). It didn’t even flick out its tongue, the serpentine version of curiosity. If a snake could have an expression, I would say it looked resigned.
The only rattlesnake bite recipient of my acquaintance was a scientist with a captive specimen. Still, it’s hard to convince people that rattlers are statistically far below bathtubs on the danger scale. Their Genesis voltage remains high enough to boil the brains of a cool customer like Joan Didion as she muses on her Sacramento Valley family cemetery in Where I Was From:
When I was in high school and college and later I would sometimes drive out there, park the car and sit on the fender and read, but after the day I noticed, as I was turning off the ignition, a rattlesnake slide from a broken stone into the dry grass. I never again got out of the car. . . .
I had seen the rattlesnake but I had failed to get out of the car and kill it, thereby violating, in full awareness that I was so doing, what my grandfather had told me was “the code of the West.”
The most disturbing snake experience I’ve had in the Bay Area wasn’t with a rattlesnake but with a common king snake, which, because it preys higher on the food chain than gopher snakes and rattlesnakes (in fact, on gopher snakes and rattlesnakes), is less numerous. I was at a stable getting manure for a garden when the bottom of the hole I was digging suddenly turned into a big black-and-white-banded snake. It didn’t do anything except crawl deeper into the dung heap, but the surprise was dizzying. There’s something powerfully chthonic about a black-and-white-banded snake, and I’ve always felt a frisson about seeing king snakes emerge from the ground, which is how I’ve usually—albeit infrequently—seen them.
Ted Hughes, English poet laureate from 1984 to 1998, evokes this in a poem about a 1959 trip across America:
WE CAME TO A STONE
Beside a lake flung open before dawn
By the laugh of a loon. The signs good.
I turned the stone over. The timeless one,
Head perfect, eyes waiting—there he lay
Banded black,
White, black, white, coiled. I said
“Just like the coils on the great New Grange lintel.”
One thing to find a guide.
Another to follow him . . .
—“The Badlands”
King snakes’ rattler diet certainly gives them cachet. And they are beautiful snakes. I think the other king snake species that occurs in the Bay Area, the mountain king snake, is the most beautiful snake in the West. It is banded black, white, black, red, black, white—as Ted Hughes might have described it. But I haven’t seen it here.
I’ve seen ring-necked snakes here about as often as common king snakes, although that’s not necessarily proof of rarity. One study estimated a population of nine hundred ring-necked snakes in an area the size of a football field. They are pretty little snakes, maximum length about three feet, with orange or yellow neck rings and bluish bodies. A smaller local snake may be even more numerous, although it’s hard to tell because it’s even less visible. The sharp-tailed snake is the smallest I’ve seen here, eighteen inches maximum, and it spends most of its sedentary life underground, emerging at night to eat slugs.
The strangest snake I’ve encountered in the Bay Area is the rubber boa, which, as its name implies, belongs to the group that includes pythons, anacondas, and boa constrictors, the ultimate World Serpents. Rubber boas are even more archetypical than giant pythons because they are a relict of the late dinosaur age—long before gopher snakes and rattlesnakes. They are as efficient at constricting their prey as their big relatives: Harry Greene, a snake expert formerly at UC–Berkeley, recorded one individual that had just eaten three moles. Their maximum length is thirty inches, however, so they tend to be overlooked. I thought a foot-long one that I encountered on the Coast Trail at Point Reyes National Seashore was a piece of brown-and-yellow bungee cord until