MOUNT VERNON, Wash. -- A teenage boy who said he thought he was shooting at a bear when he fired a round that killed a hiker was found guilty Tuesday of second-degree manslaughter.

Skagit County Superior Court Judge Susan Cook ruled that the teen's actions were a "gross deviation" from what a reasonable 14-year-old hunter would do.

She determined that the boy and his older brother, who was with him at the time, could not have clearly seen the target when the younger boy shot and killed 54-year-old Pamela Almli on Sauk Mountain last August.

The teen was charged with first-degree manslaughter, but Cook acquitted the boy of the more serious charge, finding he didn't act recklessly. But she says it wasn't a hunting accident.

Prosecutors said Almli was shot in the head as she bent over to put a jacket into a backpac when the boy fired a .270-caliber rifle from about 120 yards away.

The boy's defense attorney argued that the teens thought they saw a bear through the fog rolling in and out.

"At the moment he took the shot, he knew it was a bear," said defense attorney Roy Howson. "And his older brother said, 'Indeed, it was a bear.'"

Prosecutors said the teen failed to follow guidelines in the state's hunting safety manual, including being sure of a target and what lies beyond it.

The teen is scheduled to be sentenced July 10.