JACKSON - A Bear River man pleaded guilty Tuesday to poaching an elk in Grand Teton National Park.

William Thompson, 18, entered a plea agreement with the U.S. Magistrate Court in Jackson, pleading guilty to the illegal taking of wildlife. Although the charge carries a maximum penalty of $5,000 and/or six months of jail time, plus $6,000 restitution for the animal, Thompson's penalty was only $125, plus a $10 special assessment and six months of probation.

Assistant U.S. Attorney Kerry Jacobson told the court she agreed to the plea agreement because Thompson has given "substantial assistance to the United States to further its investigation."

Magistrate Judge Jim Lubing told Thompson, upon accepting the plea agreement, that he is expected to help prosecutors with their case and may be required to testify during a trial.

Jacobson also told the judge that Thompson was following instructions from two adults in his hunting party.

"It was felt that if you're that age, you follow the adult direction given to you," she said. "He immediately gave information to the ranger at the scene, and he has given us assistance throughout."

Thompson was hunting Sept. 27 with Jeffrey Wisenbaker, 36, of Evanston, Chadron Wisenbaker, 18, of Fort Bridger and another man identified in Magistrate Court Tuesday as Randall Johnson. The men shot and killed three bull elk inside Grand Teton National Park, near the Arizona Creek drainage.

Chadron Wisenbaker and Thompson were charged with illegal taking of wildlife and illegal possession of a firearm inside a national park. Jeffrey Wisenbaker was additionally charged with interfering with agency functions by making false statements.

No charges have been filed against Johnson.

Lubing asked Thompson what happened that day.

Thompson, wearing a striped shirt and jeans, said he was hunting in Arizona Creek and came upon an elk after walking for 30 minutes. He said the adults in the party told him he could start hunting.

He shot the bull elk, and a park ranger came up to the group and "informed me I shot it inside the park," he said. "I said I wasn't aware of the boundaries."

Lubing asked what he had done to "ascertain if you were in the park."

Thompson said the night before, Johnson spoke to a park ranger who said if you walk 30 minutes through the park, you'd be in Hunt Area 71, where the men could legally hunt.

"We thought we had walked through the park to Hunt Area 71," Thompson said.

"Apparently not, huh," Lubing said.

Thompson said he was following Jeffrey Wisenbaker.

Lubing asked how big the elk he shot was. Thompson said it was a "six by six."

"Is that the biggest elk you ever shot?" Lubing said.

"Yes, sir," Thompson said.

Jacobson said the men were told if they walked 30 minutes on the trail they would be in the Bridger-Teton National Forest. The men chose instead to walk along the creek bed.

"Common sense tells you you're not going to go nearly as far on the creek bed than on the trail," she said. "He did know they disregarded advice on how to get there."

Still, Jacobson said Thompson "immediately" admitted to killing the elk.

Lubing asked Thompson if he was "recklessly unaware" of where he was when killing the elk.

"Yes, sir," Thompson said.

Lubing also asked if there were any signs that the men were leaving the park, and Thompson said no.

Lubing told Thompson he was accepting the plea agreement, but that things could have gone worse for the 18-year-old.

"You have an obligation when you're out there hunting in Wyoming to know what you're doing," he said. "The agencies are pretty protective of wildlife. It's big business."

Charges of carrying a loaded firearm in the park and illegally possessing a weapon in the park were dismissed.

Meanwhile, the court set a date of April 25 for a trial in the case of Jeffrey Wisenbaker, who was not in court Tuesday. His lawyer asked for the date to be set "as far down the road" as possible.

Wisenbaker has repeatedly said he intends to plead not guilty and that there are long-standing boundary issues in the park.

Chadron Wisenbaker was not in court Tuesday, and Lubing said he had heard from his attorney but not Wisenbaker. He said it sounded like there is a need for a trial.

Lubing delayed that case to Feb. 15, and said if Wisenbaker did not appear, a warrant would be issued for him.

Reporter Whitney Royster can be reached at (307) 734-0260 or at royster@trib.com.