It has not been proven yet that Blondes are found throughout or adapted to that entire range of caliche-encrusted limestone (although it's fairly obvious to collectors that they are and have), or 'light-colored limestone', as you put it. But for argument's sake, let's say that it has, hypothetically.



So, as a conservation biologist whose job it would be to protect a recessive variation that has been seen since at least 1966, and made the measurements you've made of their probable range, you would take the most conservative estimate of the snake's range. In other words, you would ACT and make decisions based on the smallest of your measurements.



34.5 miles of habitat is TINY. That's less than 7 x 5 miles. You could walk that easily. That's basically a habitat island with, as we've seen and discussed, very little dispersal outside of it. If that's all there is in the world for that species to survive on, that is eensy teensy. Even the larger estimate which is only 10 x 14 miles is very small. Of course, it's a long and skinny L-shaped habitat island, so there is a lot more edge habitat than if it were a simple 7x5 or 10x14. Edge habitat makes the situation all the more precarious.



The point is not that you're driving through a tiny section of their habitat, it's a transect of their habitat. Do you think that Blondes are staying in one spot on the caliche? They're moving around, and that's how we find them when we drive. It's like riding in a car in the same straight line in a baseball field with players that are moving around alot. You do it enough and eventually you're going to run into a good number of the players.



Now, let's do what most herpers do and try to avoid hitting the normals in that "baseball field" and and hit all the Blondes. Based on estimates, homozygous Blondes make up less than probably 5% of Subocs seen through that transect of prime caliche. What happens when there are 100 subocs, five of which are Blonde, and you take just one Blonde. That's 20% of the homozygous Blonde population take, which is very significant in regards to its effect on drift. You've now changed the whole dynamic of genetic drift. I don't think you understand or know what genetic drift is. Or especially its effects on an infrequent allele.



Blonde habitat is a tiny island where selection apparently favors Blondes, but where you have normals invading the gene pool and therefore working against selection from ALL sides of the habitat island. The selection will probably keep the Blondes around (until the caliche erodes), but the immense number of normals that are omnipresent and invading Blonde habitat from every point will keep Blonde numbers low.



Again, do you grasp the Nerodia sipedon study I provided, or did you even read it? That's what is going on here, in a nutshell, with the Blondes.

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