Reptile & Amphibian Forums

Hey all, I live about an hour north of LA and have been noticing 2 very different color variations in the S. Pacific rattlesnake (which is the only rattlesnake we have here). One is the typical cream colored base with rich or dark brown blotches along its back, in general a fairly high contrast snake. And then the other type which I have just recently been finding is a very melanistic snake, black with just a faint outline of what its pattern should be showing up as thin greyish lines. Does anyone know what causes this? I am wondering if its a genetic thing, since I have found both types right in the same area. Sorry I don't have any pictures, I dont have a camera at the moment. I'll see if I can borrow someones and post them up though.

Thanks for any input!

Rory

Melanistic Southern Pacifics are found typically at higher elevations of the "Angeles Crest" and the San Jacinto Mtns as well i.e; the home to the town of Idlewild. Once you start seeing pine trees you're in dark/black southern territory. Presumably an adaptation to the colder temperatures found therin, imagine the difference a melanistic snake has in attaining a desirable body temperature when exposing some small portion of it's body in a rock crack let alone laying out fully in early spring or late fall sun. Another interesting note is their ability to change color from a grey to dark black and back again. Arizona Black Rattlesnakes also display that trait.... the change may be related to light cycle (day or night) or stresses on the animal, not simply temperature. I have personally seen a cerberus turn from a deep black to a light grey unrecognizable animal complete with classic facial stripes merely after a car ride!