The grizzly bear sank its teeth into Ben Radakovich's back, at one point lifting him from the ground and shaking him hard as it mauled him on an Alaska trail.

The 30-year-old man recalled that as the enraged bear with a young cub pounced, he had no time to fear death: just a split second to yell and step back.

"I didn't really think anything," he said after Sunday's attack during a solo hike along the Penguin Creek Trail south of Anchorage. "I was just reacting instinctively."

It was only later that Radakovich contemplated all the what-ifs. What if the grizzly had bitten him a little harder on the neck or gotten an artery or his spinal cord? What if Radakovich wasn't wearing a backpack that held the hard hiking helmet the bear dug into first?

As it turned out, he was rescued after he scrambled 30 feet up a tree. He was left with wounds in his lower back and a lacerated neck, requiring multiple stitches to close up. He feels stiff, bruised and sore.

"I'm just thankful that it didn't turn out worse," he said Thursday by telephone from his home in suburban Anchorage. "If that bear wanted to kill me, it easily could have."

Radakovich moved with his family from Moscow, Idaho, to Alaska, where he and his wife, Tami, work as public school psychologists in Anchorage. They love the outdoors and like to go camping and hiking with their three children.

Radakovich was eyeing the Penguin Creek Trail because he wanted hike up some peaks.

He was an hour into the hike where the trail is narrow and winding, closed in by thick foliage. Bears were uppermost in his mind, so he kept calling out "hey bear" and "out of my way bear" to warn any of his presence.

But the mother grizzly was just around a bend in the trail, poised to attack. Radakovich dropped one of his hiking poles and reached for his bear-repellent spray on his belt. The bear jumped on him, knocking the spray out of his hand and going for his backpack.

Radakovich curled up in the fetal position. The bear lifted him with its teeth and shook him. He clearly remembers also being bitten in the neck. He doesn't know what happened for several seconds, and wonders if he passed out.

"I just remember sitting and realizing the bear was gone," he said.

He called 911 on his cellphone but hung up when he saw the bear coming back. He quickly climbed the tree and called again.

For nearly a half hour, he could hear the bear grunting below him.

Rescuers reached him after nearly two hours and he was flown by helicopter to an Anchorage hospital, where he was treated and released that evening.

Radakovich says he and his wife won't be making any more solo treks in certain places. But he knows even people in groups can be vulnerable: Four teenage wilderness survival students were attacked by a grizzly in Alaska's Talkeetna Mountains last year and survived.

"There are things you can do to make yourself safer, but bears are unpredictable," he said. "You can never be 100 percent certain that you'll have the time to fend off a bear."