May 27, 2015. On our southern Cochise County (Arizona) acreage, we have both Mojave green and western diamondback rattlesnakes. Knowing how to identify, differentiating Crotalus atrox from Crotalus Scutulatus–and in a hurry at that–is crucial because, while antivenin is available at the local hospitals, the two species pack very different venom. Snakebite treatment with the wrong antivenin could prove even deadlier than the original bite.
Never mind the hybrids. My wife and I are convinced the Mojaves and westerns do interbreed at times. At any rate, it’s known that in certain specific areas, it’s possible to encounter a rattler identified as a Mojave green carrying both venom types, a one-two poison punch.
So, to the point: How does one instantly know the difference between these two when encountering them in the wild? After all, there are obstacles. They’re very, very similar in appearance. The Mojave often has a greenish tint to its scales, hence the term, “Mojave green”…but not in every individual and not in all types of light. (We’ve noted that coloration under bright sunlight only; it does not seem to show up at all in the beam of a flashlight or even in ordinary shade on a bright day.) The diagonal stripes on the sides of the head are different, but few of us are going to get close enough to study that little detail on a live rattler. Terminated buzz worms (as some Californians used to call them) have often lost their heads entirely–at least if a shotgun was used to do the terminating. The same goes for the supra oculuars (scales over the lidless eyes) and the scales between the supra oculars.
All of this head scratching leads us inevitably back to the one easily seen (much of the time) black and white coontail stripes on the tail, just ahead of the rattles. As I’ve mentioned in numerous posts, Mojave greens have white bands that are noticeably wider than the black bands whereas western diamondbacks have bands of roughly equal width.
That said, I wasn’t prepared for the tale my wife had to tell when I returned from town this afternoon.
“Do western diamondback rattlesnakes and desert cottontail rabbits cohabitate?” She asked?
“In the sense that rattlers eat rabbits,” I replied.
“Oh. Well. Out behind the far storage shed, there was a little rattler in a resting coil and a bunny sitting right behind him like they were buddies.”
“That,” I observed, “may be where the term dumb bunny comes from.”
“I threw a rock at the shed and–”
“Threw a rock. The rabbit had already gone under the shed, but then the snake did, too.”
For the new reader, it’s important to understand that my 63 year old, five foot, Alzheimer’s victim, anorexic little wife is…well, she’s never boring.
“Babe, don’t ever throw a rock at a snake–”
“I wasn’t trying to hit it. I threw it at the shed.”
“Yeah, but you alarmed both of them, the rabbit and the snake. Don’t ever throw a rock at a snake unless you know you can kill it. Which I’ve done, but killing a rattler with nothing but rocks isn’t all that easy. You have to know what you’re doing. And I would never—
“I just killed my bunny, didn’t I?”
“Don’t know. Let’s go snake hunting.” We do not like terminating the pit vipers, not one bit, but we can’t afford to leave them roaming around in our high traffic walking areas near the Border Fort, either. Right now, Pam weighs 82 pounds; one venom-whap would kill her stone cold dead before the Life Flight helicopter could even get here. Her balance isn’t that great, either; she could fall on a snake. “Show me exactly where you saw the rabbit and the rattler.”
She did. “Okay, now you keep an eye on the hole–not that I expect the snake to come crawling back out this soon, but just in case. I’m going to get the Maglite, shine it under there, see if I get lucky.” Pam’s reptile sighting had happened no more than ten minutes before I got home; there might be a chance.
On the return trip, cutting through on the gravel path between sheds, I saw…”Pammie, come over here, please.” She came walking slowly and carefully around the shed, which she has to do with her balance problems. I pointed under the near front corner of the steel storage shed. “Is that the same snake? You’ll have to squat down to see it.”
“Where–oh, there. Yes. Yes, that’s the same snake.”
The rattler didn’t seem bothered by the Maglite I shined its way, so I took the time to snap a couple of photos including a close-up (via zoom lens, thank you very much). As Pam pointed out later, “I’d have walked right by there and never seen it.”
“They don’t jump out from cover at you.”
“They don’t? That’s good to know.”
“Why would they? They only strike when they feel threatened, and they feel safe with a roof over their heads.”
By the time she was behind me and I’d donned my shooting muffs, she was on the phone with her friend Jesse, giving him a blow by blow account as he encouraged her. “Do exactly what your husband says.” I like the way this guy thinks. I spoke in my head to the reptile, “Sorry,” and pulled the trigger. A .410 is a lightweight shotgun, but it still packs a lot of punch, even when loaded with #6 birdshot. When the dust cleared, I had to go rig a long snake-snagging wire to retrieve the carcass.
Yep. Western diamondback, all right. See how close the white and black bands are to being equal in width?
Yes, at least one of those white bands on the western does look a bit wider than the adjacent black bands, but the difference is nominal in comparison with the Mojave green rattlesnake ratios as shown in the photo below of a Mojave killed out behind the house a couple of years ago. In the middle of one late summer night, I came within one pace of stepping on that one.
Pammie was feeling bad about the whole experience, from doing the “wrong thing” in throwing the rock to having to watch me terminate the rattler. Jesse and I both assured her that she’d actually done the right thing even if it was only by accident that she scared the young 23 inch snake so much that it had traveled from corner to corner under the shed, ending up in a position visible to the guy with the shotgun. “Hey, babe, you probably saved at least a dozen bunnies!” This fairly small viper may have considered full grown rabbits a bit too big for its gullet today, but baby bunnies would be oh so delectable…and at some point a growing rattler will decide, “Yum! Rabbit!”
Beyond that, once a rattlesnake takes up residence in the middle of a major rodent population center, the snake’s major food group takes a very long time to recover. In 2012, I missed a 30 incher that made it down a spotted ground squirrel hole before I could get a shot off. The same snake surfaced three months later and was terminated, but by then the ground squirrel colony had become a squirrel ghost town. The little cuties still aren’t back, and we don’t blame them.
Curiously enough, Pammie has a sixth sense that tells her which species she’s seeing. She informed me from the beginning that this one was a western diamondback. That’s most interesting, especially considering the fact that her eyesight is not the best; she certainly did not make the determination by eyeballing the coontail difference. Rather, as she puts it, “I felt less danger from this one. Not a lot less, but some. So I knew it was a western.” Living around the critters as we do, I’ve developed a bit of that talent as well…but not to her level.
UPDATE: May 30, 2015. Pam called me while I was out running errands today. She was ecstatic. Right in the exact same spot where she’d first eyeballed the rattler, there was a really young baby cottontail just hanging out, getting it figured out how to graze and browse. That little bunny would have been a perfect meal for the terminated snake…which meant she knew she’d helped the little rabbit be safe by playing her part in the demise of the diamondback…and the bunny was even friendly, too, not overly alarmed by her presence. That was definitely cool. I got home about an hour later and the widdle wabbit was still there, so I quick-like-a-bunny got a few photos. Might as well add one below this paragraph, right?