Federal prosecutors can chose which court to prosecute you in, it doesn't have to be in yours or where the crime took place.
There's a bit of a precedent from when a guy was charged with illegally shooting an elk in the Montana part:
http://billingsgazette.com/news/state-and-regional/wyoming/yellowstone-no-man-s-land-leaves-jurisdiction-question/article_f4caad4c-fd01-5e78-b2d9-1a0cf37b4855.htmlThe judge dismissed this argument but couldn't really explain
why. the case could've gone to an appeal where a court would have to rule on that but he took a plea deal prior. Leaving this still an awkwardly unanswered question.