The hiker was found in a narrow valley northeast of the Three Sisters dam, south of the town of Canmore, Alta. (Tom Spear/CBC News)

Searchers have found the body of a Calgary hiker swept away by an avalanche near Canmore.

The 37-year-old man was hiking with a friend, heading down Big Sister Mountain, when they decided to slide down a slope and were caught in a small avalanche at about 2:30 p.m. Wednesday, rescuers said.

"Two individuals were coming down the west ridge and they were sliding down the snow slope, and the snow slope avalanched and released. One of the people near the top, he was able to roll out of it and watch his friend disappear round the corner and over a cliff bend," said George Field of the local search and rescue operation.

The hiker who survived tried to help his friend, but gave up and alerted officials.

Big Sister Mountain, which has a well-used hiking route to the top, is across from the Three Sisters dam, south of the town of Canmore on Spray Lakes Road.

A search began Wednesday but was called off as darkness set in and rescuers grew concerned about the possibility of another avalanche, the RCMP said. The search continued Thursday morning with the help of a rescue dog and the hiker's body was found under half a metre of snow.

The avalanche danger in the popular recreational area wasn't specified as particularly high, said Staff Sgt. Patrick Webb.

"But at the same time, all of the mountains right now are in high danger of avalanche. Snow conditions and weather conditions put the danger up to extreme, and in this case it did come down," he said.

Avalanches have killed 13 people around British Columbia this winter in conditions that have often been rated extremely dangerous. Eight snowmobilers died in late December in a series of avalanches near the southeastern B.C. community of Fernie.

With files from Canadian Press