Wildlife experts on Tuesday were finding no unusual stress factors that might have prompted a large black bear to attack and kill 11-year-old Samuel Evan Ives in American Fork Canyon.

But simple proximity of humans and bears seems to guarantee that more conflicts are inevitable, said the director of the Utah Division of Wildlife Resources.

Jim Karpowitz added that Sunday night's "horrible, tragic bear attack" could be just the start of bear problems this summer.

"Bears are all around us" on the Wasatch Front, he said. "They are on our doorsteps" because of the proximity of homes to forested mountains.

"There are more bears around these days, more people camping," he said.

Karpowitz predicted interactions between humans and bears will increase. Bear problems have already occurred in northern and northeastern Utah this year, he added.

"We are working very hard, under our bear policy, to deal with those right now," he said.

The boy's family, residents of Pleasant Grove, camped a short distance north of Timpanooke campgrounds in the Uinta National Forest. Late Sunday night the bear ripped through the tent where Samuel was sleeping and pulled him outside while the boy was in his sleeping bag. Awakened by his screams, the family tried to find him but could not.

Two hours later searchers discovered Samuel's body about 400 yards from the tent site. Trackers with dogs killed the bear, estimated at between 300 and 350 pounds, about 11:30 a.m. Monday. A necropsy (animal autopsy) at a state laboratory based at Utah State University confirmed it was the same bear.

Hal Black, professor of wildlife biology at Brigham Young University, said the bear's weight probably was about 300 pounds, "which is an early summer bear." He talked with a friend who helped track the bear and load its carcass.

After gorging all summer, a large adult black bear could weigh 400 pounds before it hibernates, Black added.

This animal looked like a healthy, mature male bear. It did not seem emaciated, the friend said.

Bears are omnivorous, eating nearly any potential food they come across from fish to grass, ants, mice and deer. At the elevation where the attack occurred, possibly around 9,000 feet, fresh forbs and grasses were available for the bear to eat.

"To think that he was starving is probably nonsense," Black said. "He looked healthy."

The bear's age was probably 6 to 9 years, based on size and the fact that the canine teeth were not yet ground down, he said.

This time of year, bears tear open logs and stumps and eat insects inside, like ants. Also, "They're eating wasp's nests, which seems like a tough way to make a living," Black said.

Male bears cover more ground than usual around this time, searching for female bears. Possibly its travels brought it to the campground.

"It could have been his first time in a campground or he could have been experienced," Black added.

Bears can smell food from a mile or two away, according to Black.

"I don't know what happened at the campsite. But this is not an unusual thing, for a bear to be smelling a human on the other side of the tent," he said.

The night before the attack, a bear ripped the tent of a camper in the same vicinity.

"If you're a 300-pound animal and you've got nice long claws, and you lean up against a canvas tent," Black said, "you might fall through it."

While an investigation will tell whether the bear was diseased, Black expects it was "a healthy animal. It was out foraging."

Barrie K. Gilbert, a noted bear researcher formerly based at USU, said he thinks the deadly attack was "truly an anomaly."

"It means people should be careful around bears because they're big and they're dangerous," said Gilbert, who is retired and was contacted in eastern Ontario, Canada.

Gilbert said many black bears become food-conditioned through interactions with people. They may become assertive and shove humans away from food, as they do with other bears.

He believes bears that are least familiar with humans are likely to be most assertive. "They don't recognize humans as much of a threat," he said. But where bears are hunted, the survivors tend to avoid people more.

Attacks by black bears are so rare in Utah, Colorado, Idaho and Nevada that people should not be afraid to camp outdoors, he added.

One possibility, Gilbert said, is that the bear might have heard something inside the tent that "sounded like a mouse," and pounced.

Still, large male bears can tend to become single-minded, aggressive and nasty, Gilbert said.

"They almost get cunning," he said.

Sometimes powerful males get used to "beating up just anything out there, and they'll run down anything and eat it," Gilbert added.

He praised state officials for killing this one, saying that after an animal kills a human, it "won't back off" and will seek out others.

Housing developments did not play a role in the attack, said Kevin Bunnell, DWR mammals program coordinator.

"There aren't summer homes or anything like that near the area," he said.

But for outdoors activities, American Fork Canyon is a high-use area with lots of visitors, he said.

Did the bear attack because it had run out of natural food?

"No, right now at that elevation, things are still lush and green," Bunnell said. "They're kind of limited to eating grass, which they can do just fine on. ... But there's not a lot of variety out there right now. Berries and nuts and acorns and things haven't come on yet."

Neither is the area suffering from drought at this time of year.

"You want to make sure that you cook away from where you're sleeping," he said. "And then change clothes. You don't want to sleep in the same clothes you're cooking in," because bears might smell the food and go after it.

Also, visitors should have good hygiene, as bears can smell body odor.

"Their noses are really what they use to investigate the world around them," he said. "They're like a dog."

Bunnell said smells that don't indicate food still might prompt a bear to investigate out of curiosity.

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