Nov. 19, 2012 -- Alaska state troopers are currently searching for a 31-year-old man who set out alone on the last leg of a three-month trip into the Alaska wilderness and has not been heard from in almost two months.

When Thomas Seibold of Three Rivers, Wis., journeyed to Alaska in June he planned to put years of survivalist training into practice in the state's frigid backcountry. A native of Germany, Seibold had spent the previous six years teaching and training at Three Rivers' Teaching Drum Outdoor School, a survivalist school that teaches American Indian values along with weather forecasting, shelter building and primitive hunting and gathering techniques. He spent much of his time under the tutelage of the school's founder, Tamarack Song, who described Seibold as a very experienced outdoorsman and a "wandering spirit."

To make the trip to the Arctic frontier, Song told ABCNews.com that Seibold had taken a six-month leave of absence from Teaching Drum Outdoor School.

Seibold began his trip at an Alaska Native fish camp in the southeastern part of the state, and from there traveled north along the Tanana River near Fairbanks, all while living outdoors.

By September, Seibold had traveled to the northwest Alaska village of Ambler. Traveling ever farther north, Seibold trekked about 30 miles up the Ambler River to the cabin home of a woman Song's contacts had put him in touch with, and her 13-year-old son. Seibold remained with the mother and son until Sept. 27, when he left with the intention, Song said, of hiking farther north to Gates of the Arctic National Park and Preserve.

No one is reported to have seen or heard from Seibold since that late September day. Alaska state police were alerted when Seibold missed a Nov. 11 flight from Kobuk that was supposed to begin his return trip to Wisconsin.

Megan Peters, a spokeswoman for the Alaska state troopers, told ABCNews.com that search and rescue workers had done extensive aerial searches in the unpopulated expanses near where Seibold was last seen. Troopers were concentrating their search near the confluence of the Ambler River and Ulaneak Creek, where they believe Seibold may have built a base camp.

"He could have run into a wild animal," Peters said. "He could also be fine. But not knowing where he intended to go makes the search more difficult."

According to Song, Seibold has camped alone in extreme northern wintertime climates before, but that he "has always been responsible and clear about his intentions" when striking out alone. Song said an unfinished letter Seibold left behind at the cabin indicated he only intended to be gone "for several days."

Those several days have stretched into almost two months, but Song expressed confidence that as long as Seibold's faculties remained intact, he could survive.

"He is well-experienced," Song said. "He's gone on reindeer hunts in Norway's interior. He's a midwinter guide. If he's not injured or delirious, he will stay alive."