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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_ (http://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