Actually, you may wish to "skip across the pond," and check out the programs offered at the University of Canberra, Australia.
They have an excellent Environmental program, with a lot of ongoing research geared towards the herpetofauna you have described.

Here's the URL: http://www.canberra.edu.au/

I am not too familiar with any So. African or UK programs, with crrent, or on going work, in the areas you described, though I am certain someone else on this forum may be aware of such.

Best of luck to you,

Jeff Snodgres
University of Arkansas
snodgresjeffreys@uams.edu
501.526.4856