Rappelling down a 650-foot cliff to catch seabirds on a remote island just below the Arctic Circle was scary enough.

“The first time you look over and you rappel over, it’s certainly not for the faint of heart,” said Kyle Elliott, a research chair in Arctic ecology at McGill University in Canada.

But for Elliott and fellow researcher Emile Brisson Curadeau, it was the hungry polar bears (Ursus maritimus) — usually one a day walking near their cabin — that raised real concerns, and devoured their research subjects.