Reptile & Amphibian Forums

I brought this up because of some comments made in the photo gallery about a scalless rattle snake. The argument was that the morph was simply due to inbreeding. My thought was that many types of rattle snakes have their own sort of populations because of den sites. Some species, such as Timbers, could have very isolated den sites for reasons such as surrounding habitat loss etc., but within the area the snakes always seem to be healthy. There has to be a large amount of inbreeding if a den site is isolated right? So if inbreeding is the cause of morphs etc. such as this, wouldn't we see a lot more of it in rattle snakes in the wild? I'm not saying that all of this is correct, it's just my theory... any thoughts?
-Will

at least not for the Az. Blacks I have watching for 15 years, but from what I can tell timbers seem pretty much identical in habits so I would bet they are the same. Breeding season for both these species actually starts mid summer, when the snakes tend to be well away from densites, and goes till Sept. Males for both these species have very large ranges, sometimes over two miles in radius. Females that are not gravid also move about a summer range that is smaller. The range of males usually overlap those of several females including those from other densites, so there is actually a good amount of gene flow.

The PRIMARY breeding season is mid summer. I do see occasional spring breedings in Az. Blacks upon emergence from hibernation (in teh northern populations anyway, southern pops seem to be exclusively summer breeders), and there was I time when I believed this was the primary season but have since learned otherwise.

Actually, there are DNA studies under way right now here in Pennsylvania investigating the inbreeding issue. Here in PA, the timbers inhabit rocky mountain ridges, which can be isolated as development increases at the mountain bases and along the ridges themselves. Highways and human disturbance are also factors. I'm not sure if any conclusions have been drawn yet but it's an interesting subject.

A good example of a population of snakes which are inbreeding at the moment are Captive bred San Francisco gartersnakes (Thamnophis sirtalis tetrataenia) in Europe. These animals have been inbreeding for at least 10 generations. The only problems that are occuring at the moment are smaller broods and as I am tolld a limited lifespan for females.

So I don't think that the scaless timber rattlesnake is caused by inbreeding, I think it is caused by some sort of mutation. Similar to a snake with 2 heads.