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Perhaps some of you may enjoy seeing photos of a fine diamondback that I almost stepped on yesterday. Apologies to those who have seen this already.
 
The sighting provoked a comment from Paul Moler, herper extraordinaire, who somewhat jokingly suggested that being venomous was the one shared characteristic among the few reptile species not in catastrophic decline here in north Florida. I answered that it was prey choice, and thus exposure to ranavirus. See below:
 
Sleazel
AKA: Bruce J. Morgan
Environmental Designs
POB 1519
Archer, FL 32618 USA
352 495 9748
www.environmentaldesigns.org
 
 
So there I was being super surreptitious as I scouted a way through the palmettos when I looked down by my foot and saw this.
 
 
That's about a four and a half foot Diamondback rattler. My foot was about six inches from it's nose when I went airborne. Worse still, I had been standing there fidgeting around for several minutes trying to find my way past a Lyonia thicket so the nipper had lots of reasons to get riled up but didn't.
 
Notice the "please don't step on me" posture with the head drawn back in a hook. Totally passive defense. That is because it knew that I hadn't seen it, I was just another clumsy klutz to be avoided, no need to waste valuable venom.
 
So I retreated about thirty feet away and watched. As soon as I appeared to be gone Mr. Nipper started to rapidly crawl in the opposite direction. When I approached again it was obvious that I wasn't an innocent bystander so pretense was put aside and it was time to coil and rattle.
 
 
Such forbearance! If rattlesnakes were even one hundredth as mean as people imagine them to be then I wouldn't be sitting here drinking a beer and writing this story.
 
This incident occurred while I was scouting and chopping Weazel Way South just south of the Gainesville Hawthorn trail and not far west of Prairie creek. This is the forth rattler I have found while chopping Weazel Way so step lively out there!
 
SW
 
Sleaze:
 
But you said there weren't any more snakes out there. I took you at your word and started going barefoot. That was, until Thanksgiving day when I saw a deadly coral snake in woods along the Santa Fe. And a couple of weeks ago a red-shouldered hawk flew over my drive carrying a ground rattler. Maybe it's just the non-venomous serpents that have disappeared.

Paul Moler
Florida Fish & Wildlife Conservation Commission
1105 SW Williston Road
Gainesville FL 32601
(352) 334-4217
 
Paul:
 
It is not a matter of being venomous, it is a matter of what you eat. Rattlesnakes eat warm blooded prey that don't carry ranavirus. Coral snakes eat tiny reptiles such as ground skinks that never eat frogs. They might well eat a young natricine but it is entirely possible that said young natricine has not yet had a chance to become infected by ranavirus; whereas if you were a kingsnake that routinely eats adult natricines it is inevitable that you will get infected and die.
 
Green snakes, which eat bugs but not frogs, are still out there. Redbellies, which specialize on slugs and worms, are still out there too. Ringnecks which eat salamanders have gotten relatively scarce.
 
Ratsnakes are a curious case. I have had great difficulty getting neonates to accept pinky mice. They seem to want something else, perhaps frogs and lizards, though a small percentage readily accept pinkies. As adults they exclusively eat warm blooded prey and thus have no contact with ranavirus. That would explain the disparity in the ratio of adults to young that I have observed. In the bad old days I often found baby ratsnakes, now it is mostly adults. Cornsnakes are a different story. Once common everywhere, they now seem to persist mostly in urban areas. Is it possible that young cornsnakes are more likely to eat frogs than young ratsnakes? I don't know. Do you?
 
As for the frogs, you will notice that hylids have made a fair comeback this year. That isn't just because it rained this year, it is because they breed in temporary ponds that have been dried up for several years, thus killing the pathogens. Frogs that breed in permanent or semipermanent wetlands aren't doing so well, perhaps because bullfrogs, which appear to be partially immune, serve as reservoirs for the disease.
 
As for moccasins, damn if I know. They seem to be immune to everything, even rednecks!
 
I don't know how long ranavirus can persist in a moist environment, or how long infected animals remain infectious, but an unintended experiment is underway. As you may remember, my turtle pen is in a warm moist environment with trees, dense vegetation, deep humus, and a fairly large pond with deep sediment and Gambusia. The conditions are very natural though perhaps a bit too shaded, good for box turtles but not baskers.
 
About ten years ago all but two of my turtles died during what I presume was a ranavirus epidemic, the most notable symptom being that their feet rotted off. An adult Terrapene carolina major and a Cuora amboinensis were both infected but recovered and are alive today. The pond was never cleaned in any way, and bullfrogs come and go at will. The bullfrogs never died out even during the height of the epidemic, though they have declined since in regard to both size and number.
 
As an experiment, about three years after the epidemic I introduced a box turtle from northern Alabama. It was dead within a month.
 
This spring someone placed two adult redbellies (Pseudemys nelsoni) in the pond without my permission. They were obviously someone's pets as they were quite tame. They have thrived thus far, though with the onset of cold weather their behavior is more difficult to observe. If they make it through till spring I will tentatively conclude that the epidemic has finally run its course and that the two previously infected turtles may still be carriers but are no longer actively infectious.
 
We need to know how ranavirus persists in the environment. Does it persist in moist or wet sediment? Or does it persist in previously infected animals? I think we need to look more closely at bullfrogs and fish. Gambusia are omnipresent and do not seem to be affected, could they be carriers?
 
SW