I've caught a much smaller one (Ridley's) about 12" carapace in a trawl off the mouth of the Mermentau in the early '80s. It must have been caught just before we pulled in the tailbag because it was still fairly lively and swam off in great haste once released. I have seen many of them while fishing rocks from 80 up to 300' of water. Those suckers will get 5+ feet and several hundred pounds. They are very good eating....at least the legal ones are
. The Cayman Islands had a turtle farm on Grand Cayman and sold some meat to the local restaurants and it is great in a stew or brown gravy.