Observed Use of High Temp Areas

From another thread. I thought I would move it here so as not to totally hijack the other thread.

The question posed was: Would a snake in the wild voluntarily use surface temps 100F+?

And if so, what are the environmental conditions that would warrant such use?

Chip said the following

Yes. At least on *part* of their body they will. I've seen wild water snakes throw a coil over a supremely hot surface (150+) in the sun for a minute, move it a few inches, then dip back under water many times. I have caught many corn snakes on hot roads after a rain and quick temperature drop. Snakes can be collected under tin so hot that they don't even feel cool to the touch like our captives do.

I disagree.

1. Was the wild water snake wet when it first touched the hot rock? Latent heat exchange would effectively reduce the sensible heat change to 0 for the animal. Like stepping out of a pool onto hot concrete, as long as your feet are wet, it doesn't burn. Once feet are dry, you can feel how hot it is, and so you step into the grass, jump back into the pool, or scream in agony. The snake chose option 2.

2. Snakes in the rain is the same deal with latent heat exchange. They're wet, the road is wet, and I bet they're just passing through too. El Jefe had some interesting points about road cruising and snake temperatures.

3. A snake under hot tin is much different than one on the hot tin. I suspect the temperature under the tin is radically different than the temperature on top of the tin. The shade provided by the tin can make a 10F temperature difference alone. Secondarily if there is any evapotranspiration gonig on, if the snake is in vegetation under the tin, or any soil moisture (again with latent heat exchange perhaps). Plus the tin might be reflective too, deflecting quite a bit of shortwave radiation away from any creature underneath.

I could be wrong on all of these counts as I am not a snake, but I bet there are many more processes to sensible heat regulation for a snake than we sometimes think about.

So yeah a snake may encounter 100F+ temps in the wild, just as it might encounter a hawk or a hiker, but is it going to use them? Do we have any evidence that it is using the 100F+ temperatures? I have yet to find any.

Oh yeah, and somebody did do a study implanting temp probes into snakes. The article title is: Body Temperature Variation in Free-Ranging Hognose Snakes (Heterodon platirhinos).

We observed 49 cases during the activity season in
which H. platirhinos were tightly coiled, fully exposed
to solar radiation, and judged to be ‘‘basking.’’ In 40 of
the 49 cases, Tb ranged from 0.3–11.7C (mean =
4.8C) above Tair (mean = 23.1C; range 14–29C). In
nine cases, Tb ranged from 0.0 to 25.5C (mean 5
21.9uC) below Tair (mean 5 22.7C; range 16–28C).

Tb = Body Temperature
Tair = Air Temp

At least for these Hognoses, basking is important.

Single environmental temperature measurements
often explain only a relatively small amount of Tb
variation in snakes (Peterson et al., 1993). For example,
ground surface temperature explained less than 50%
of Tb variation in H. platirhinos in Canada (Cunnington
et al., 2008) and Tair explained only 37% of Tb
variation in our Arkansas study. Contributing to the
unexplained variation between Tbs and single environmental
temperature measurements is the common
temperate zone behavior of basking (Peterson et al.,
1993). Our observation of elevated Tbs in H. platirhinos
that were tightly coiled and fully exposed to solar
radiation support the notion that basking was
occurring. These observations suggest that basking
plays an important role in the thermal ecology of H.
platirhinos as previously suggested by Platt (1969).

(emphasis added)

If you take the highest body temperature above air temp (11.7C) and add that to the highest air temp (29C) you get something like 105F. I highly doubt these guys were in that range. We're talking about the extreme tip of the bell curve.

P.S. I posted this late last night so if it doesn't make sense or I come across as snarky, my apologies.

It comes across to me as if you are baiting him into a fight. I would do a bit more research before calling people out like that. Just sayin!

Well, bear in mind that the NORMAL healthy temperature of a human body is 98.6 degrees F, so I don't think 100 degrees for any animal for short periods is unusual nor particularly lethal. Matter of fact, one of the commonly known methods of a "cold blooded" animal to help cure itself of pathogens is for it to purposely raise it's own body temperature to levels that would be consistent with a fever in a warm blooded animal. And the purpose of a fever is a body's method of attempting to kill pathogens. Since "cold blooded" animals do not have any way to internally generate a fever, they have to attempt to do the same thing via external sources.

I have caught snakes that actually felt hot to the touch. Try grabbing up a black racer in the heat of the day and you will see what I mean. Coachwhips are another that seem to prefer a rather hot body temperature at the peak of their activity period.

You will also often find gravid females preferring elevated temperatures to help incubate the eggs inside of them.

That being said, in CAPTIVITY, I would not want to force any snake to have to endure such temperatures for any length of time without having any way to escape to cooler temps. But if you have an apparently ill or ailing snake, ALLOWING it to reach 100 degrees or more, if it chooses to do so, may help it cure itself. Or in the case of gravid females, elevated temperatures being available could make or break your chances of the female producing viable and fertile eggs.

Okay Rich, I'll agree with the "fake" fever thing. I have heard of that before, and it seems logical.

But, I still can't imaging a corn snake being much higher than 100F. Depending on who you ask, for an adult human, a fever becomes dangerous at 103F or 104F.

If we're going to use a human as an analog, then a corn snake wouldn't want to have a temperature of 103F for any long period of time, unless something else is seriously wrong, and then we're dealing an anomalous situation.


I was thinking more about this whole thing more today, and I realized it probably is species specific. Your desert species might use higher temps than temperate species. I have no idea, for example, what a sidewinder would seek for temperatures.

I wasn't trying to draw Chip into a fight, I just disagreed with what he said and instead of letting this discussion continue on the other thread, I moved it to here.

How much more research do I need to do? Or were you being facetious? These forums, as great as they are, fail to capture the nuances of our speech.

Chip, if you felt like I was baiting you to a fight, I apologize. I'm just seeking a well spirited debate!

Different PEOPLE will prefer hotter or colder temperatures. It may be safe to assume that in any given snake population, individual preferences may come into play as well.

There has been a tv series on in the UK called Africa.
Very interesting worth a watch if it comes to the US!!

They had a 5 minute section on the Rock Python finding a clearing to Bask at over 40 degrees it stated this would kill her after a few minutes if she was to stay there.! But she moved before that (obviously).. I observed no water and they must have measured her body temp to allow statement of fact..
This process was to raise her body temperature so high she could incubate her eggs, she did this for 60 days.
By going so high and coiling her eggs she maintained a perfect average temperature. This therefore must happen alot..

Just a recent tv program I watched. !!

Not really going to argue or really take part as I have nothing useful to add. However the gravid female thing is neat. I had a gravid black rat who I would find nearly every morning in my yard laying on the hot stone walkway one summer. The stones were very hot to my hand. Anyway, now I know why she was laying there lol.

Originally Posted by WingedSweetheart

Not really going to argue or really take part as I have nothing useful to add. However the gravid female thing is neat. I had a gravid black rat who I would find nearly every morning in my yard laying on the hot stone walkway one summer. The stones were very hot to my hand. Anyway, now I know why she was laying there lol.

Sorry I must add when she had basked she went to her burrow and then coiled her eggs!!!
Didnt mean to mislead..!!

Same theory though it takes so much energy to produce viable eggs..!!! Must be something in that..!!!

Just because one species does it is not a good argument for its commonality among any others.

I have heard of that program. My aunt told me the same thing, so it must bere in the US.

It is neat, and I won't argue with them about the African species.

it stated this would kill her after a few minutes if she was to stay there.!

So, I now have an example of a snake using high temps, but not for any length of time. 40C still only 104F...so anything 105F+ may not be used. So perhaps having a high basking temp wouldn't be a bad thing provided it wasn't any higher than 105F and the snake had a means to escape.

I'm still not convinced about corns though and more temperate species of the southeast United States.