Dan Keenan makes his way through the thick under brush in the Big Cypess National Perserve, Saturday, Jan. 12, 2013 as he hunts pythons. Nearly 800 people have signed up to hunt Burmese pythons on public lands in Florida as part of the Florida Fish and Wildlife Conservation Commission's month-long "Python Challenge." Experts say the invasive species is decimating native wildlife in the Florida Everglades. For the first time, the public is joining licensed hunters in the search for the snakes. (AP Photo/J Pat Carter)