An Alaska river guide and former National Parks Service ranger has pleaded guilty to helping a client smuggle a 10,000-year-old mammoth fossil out of Alaska. Karen Jettmar is author of “The Alaska River Guide” and the director of Equinox Wilderness Expeditions. The Fairbanks Daily News-Miner reports that she entered the plea Friday to theft of government property, a misdemeanor. Under the terms of a plea agreement, she must pay a fine of $30,000 and is on probation for three years.