http://noss.cos.ucf.edu/papers/Clark...0al%202010.pdf the other paper I was mentioning specifically - finally found it
Clark, Rulon W., William S. Brown, Randy Stechert, and Kelly R. Zamudio. "Roads, interrupted dispersal, and genetic diversity in timber rattlesnakes." Conservation Biology 24, no. 4 (2010): 1059-1069.