Ratsnakes shed old skins…with a little help
Updated: Jun 24, 2022
On warm days in this spring, an Eastern Ratsnake had been regularly visiting the deck of the cabin. Two had shed out there last year — a smallish one and a larger one — within a few days of each other. Judging by where I found the skins, the snakes were using the balusters of the iron fence around the deck to rub their old skins off.
Unlike mammals, many other animals have outer coverings that do not grow as their bodies do. Hermit Crabs, for example, regularly exchange the abandoned shell they live in for a bigger one, often creating a conga line of crabs of varying sizes waiting for the old shells to be cast off. To accommodate growth, some animals, such as snakes, instead grow a bigger skin but still need to shed the old one.
While I have found many cast-off snakeskins over the years, I had yet to catch any snakes in the act of shedding them. But, thanks to a smallish (I guessed at 3.5 feet long) snake, I finally was going to get my chance to see the process. This snake was persistent about visiting the deck, despite the attempts made by my dog, Mollie, to discourage it.
If I don’t intervene in time, Mollie’s method of dealing with snakes is to grab them behind the head and shake them. Usually, the snakes survive the attack, but I always worry that they won’t or will be badly injured. Mollie had already grabbed this snake before, and it looked like it had sustained minor damage but seemed to have recovered completely by the time it finally shed its skin.
On May 15, I glimpsed the snake on the lower rail of the iron fence, partially hidden by a plant stand and table. Its skin was turning gray at the top, along the spine, indicating it was close to shedding, and the snake was sliding along the rail, weaving through and rubbing against the balusters.
Leaving the dog inside, I went out with my camera and sat down to watch. I’d met this snake many times, and it showed little concern about my presence, just kept working at getting rid of its old skin. The part around the head was already loose, revealing shiny new black skin underneath. We’d had a lot of rain recently, and unlike last year, the skin was not coming off intact but instead patches were sticking to the wet bars.
Getting rid of the rest of the old skin took about a half hour. The most interesting part was the snake’s testing the new skin, stretching its mouth into what looked like a yawn.
The skin around the end of the tail was the last to be shed. The snake wound back through the bars again to where the branches of a bush had growth through the fence. Sliding down one of the branches to the ground, the snake took a break in a patch of sun. The rougher surface of the branches had been sufficient to peel off the last bit of old skin. I turned to other things, and within a few minutes, the snake disappeared.
Two weeks later, a larger Eastern Ratsnake appeared on the deck. This was likely the one who had left the larger shed skin on the deck last year. Like the smaller snake, this one persisted in coming to the deck for days. At one point, not seeing it on the deck when I went out onto it with Mollie, the two ran into each other, and the dog had managed to grab the snake and shake it before I could call her off.
Ratsnakes are nonvenomous and not aggressive if left alone. They are also great mouse eradicators. For both reasons, I usually give them free reign outside my home but will quickly escort out any that make it inside. In cases where I don’t want them on a deck, like when Mollie is coming out with me, I just stomp on the deck, and the snake usually gets the hint and slithers down off through one of the many gaps between the deck and wall.
On the day in question, I did stomp on the deck, but instead of disappearing under it, the snake turned around and headed toward the other end of the cabin.
It stopped at the far corner and started going up the wall. I started to worry it had picked up the scent of the phoebe nest with eggs high up on the adjoining wall, over a light fixture, but the snake changed its mind and moved down off the deck into the adjacent shrubs.
In a subsequent visit, I noticed the larger snake’s right eye was cloudy and worried that the shaking it had gotten from Mollie had blinded that eye. By the second week in June, this snake was no longer showing up, and I feared the injury had made the snake prone to predation.
Then, on June 16, while I was talking with a friend on the phone, the larger ratsnake apparently returned. I had closed up the cabin and turned on the AC unit because it was so humid. I didn’t see the snake, but Mollie kept sniffing around the closed sliding glass door leading out onto the wooden walkway on that side.
When I finally got off the phone to investigate, I found a large, shed snakeskin wrapped around the underside of a plastic garden cart I’d parked there, about 10 feet from where I’d been sitting inside but blocked from view. Mollie must have picked up on the smell of the snake, since it was probably also hidden from her view. I had been by that cart just a few minutes before I got on the phone, but now there was a snake skin wrapped around its undercarriage.
With the rough, worn edges of the garden cart, the snake probably stripped off the skin faster than the smaller snake, who took about 45 minutes. And the cart, under the eaves, was dry, so the skin came off intact. I had guessed this snake was a few inches over 4 feet long, but I’m bad at guessing dimensions of anything and I figured I’d never get a chance to measure it fully stretched out. But now that I had the skin, I carefully removed it from the cart and stretched it out. It was 58 inches (almost 5 feet) long, but the actual length of the snake that shed it is likely several inches shorter, since the skin gets stretched out when it's being shed. While this is a pretty impressive size for most Virginia snakes, this species can often reach 6 feet in length. The record in Virginia is 79.8 inches (6 feet 7 inches), according to the Virginia Department of Wildlife Resources.
The smaller snake was also still around. I saw it hanging out near the door to the basement of the main house after it shed its skin on the cabin’s deck. Earlier in the spring, I had escorted it out of the basement through that same door after it had apparently followed a mouse through an HVAC vent.
I’m no longer quick enough to grab a snake in a way that would be safe for it and me, so that day I ended up using a mop to encourage it to go out the door, which I had opened. It wasn’t overly pleased at being poked but reluctantly slithered out.
Having recently trapped several mice that got into the cabin after a torrential rain, I hope the snakes will keep hanging around. They are one of our best defenses against being overrun with such small rodents.
Update, June 24: Today I found yet another shed skin on the deck. This one measured 56 inches and was intact. While I'd noticed a snake on the deck earlier today, it had slithered down under it when I came out to make a phone call. While it looked too small to fit the skin, with the stretching that skins can undergo while being shed, it could have been the one that left it later that day.
Ratsnakes tend to shed their skins about every 4-6 weeks, with younger snakes growing faster and therefore shedding more often. Could this be the skin of the snake I saw shedding on May 15, almost six weeks ago? Or are three ratsnakes using the deck for their shedding? Since I never see more than one at a time, I doubt I'll ever know.