I plan on spending some time in that area this summer looking for caudates. I'll of course post if I have any success.
sidenote, over easter I happened to find a dead 3-toed amphiuma in a dried ditch in leflore county, MS (in the delta). It sort of surprised me because that ditch gets full sun, and under the months of +100 degree days, the ditch dries out for a couple of weeks at a time.