Hundreds of runners and spectators from the area had gathered at the Bird Ridge trail on Sunday for the race, which has been held annually for 29 years.
Troopers took possession of the victim's remains to transport to the State Medical Examiner's office for autopsy.
A park ranger shot the bear in the face, but it ran away.
His body was discovered around 450 metres off the trail in a heavily wooded area about a mile from the end of the race.
The teenager reportedly sent a text message during the race sometime after noon, saying he was being chased by a bear.
No names have been released.
Smith, with renowned bear researcher Stephen Herrero and several others, wrote a 2012 article finding no significant difference in Alaska bear encounters when people used guns versus pepper spray, and suggesting that only people proficient in the use of firearms should use them for bear protection. Crockett said that while he was talking to his brother, the teen said "there's a bear". "There's no safer time to be on a mountain than on a race", he said.
Race director Brad Precosky said the boy had raced up a mountain and was on his way down extremely steep terrain that goes through thick wilderness when the attack took place.
A day later, Alaska State Troopers were called out to investigate a fatal mauling at a mine 300 miles northeast of Anchorage.
The best defense against bear attacks, say Hechtel and others, is for people who head into Alaska's back country to carry bear repellant or guns with them.
"We have Alaska Dept. of Fish and Game staff in the field right now along with a dog handler, a noted handler, trying to track the bear", said Ken Marsh of the Div. of Wildlife Conservation. Authorities shot at that bear, but it ran off. "But, we don't know how hard it was hit - if it was a graze or anything like that".
Meanwhile, there were 15 killings of people by brown or grizzly bears during the same period and one fatal mauling by a polar bear.
The bear involved in the attack was killed. Searching for a way back to the race course, he instead found himself face-to-face with a 250-pound black bear.
Shaw told ADN that there have been previous instances with nuisance bears but never attacks or damage to company property, and it seemed to be less bear activity this year, until Monday's attack. As a family and community mourns, for now that bear continues to wander the trails.