Only carrot tails naturally occur in the South Mtns, no redbacks. Carrot tails are only found in these mountains, which is why they are protected.
All chucks there are off limits to collection. I believe collection has been prohibited since 1997 or 1998. The visitor's center for the park has more exact info. I have been there several times to photograph the chucks, and there are signs everywhere to remind visitors that the chucks may not be captured, or harassed in any way.