The story of the infamous buffalo of South Park, Colorado has been taken to the halls of the FCC by none other than Phil Weiser. [Don't ask, but since the theorem first appeared in Coase's article, The Federal Communications Commission, it seems appropriate.] The bison wanderlust was first noted here.
Now, the proposed solutions. Coase-ian in training Eric Gunning from the Law and Econ of the Information Age seminar offers this: Cosean Dilemma Bisons v. Fishing - Eric.doc
Eric's discussion is more in depth than my glib "no one owns the fish" answer. This sounds like an issue to excite noted econ-geek Lynne Kiesling, so long as she's not too busy tending to her shrine to Mark Prior, Kerry Wood and Greg Maddux.