A 24-year-old man and a 25-year-old woman working for the Alberta Sustainable Resource Development were collecting data on trees infested with pine beetles when they walked over a well-hidden bear den, precipitating a rare winter attack. A startled grizzly emerged from the den and charged the surveyors from behind, first mauling the man, then turning on the woman, according to this Vancouver Sun article. Both have had surgery and are recovering from non-life-threatening injuries at Queen Elizabeth II Hospital in Grande Prairie.