Clifford Walters, a Hawaii resident, has pleaded guilty to a federal charge and been fined after helping a bison calf out of the Lamar River in Yellowstone National Park. The calf was later euthanized, and the National Park Service has warned visitors to never approach, feed, or intentionally disturb wildlife. Walters was fined $500, along with a $500 community service payment, a $30 special assessment and a $10 processing fee.