Hikers are often taught to be wary of the mother bear protecting her cubs, but new research shows that lone male black bears are more dangerous than their female counterparts.

Most of the fatal black bears attacks in North America in the last 110 years were the result of male bears targeting humans as food, according to an article published Wednesday in the Journal of Wildlife Management by University of Calgary professor Stephen Herrero.

Researchers looked at all the black bear deaths in North America between 1900 and 2009, excluding those caused by bears kept in captivity.

The study found that 63 people were killed in 59 incidents. Of those, 88 per cent involved a bear "exhibiting predatory behaviour" and 92 per cent of the bears were male.

The findings can be used to better understand the cause of attacks and how they can be avoided, said Herrero.


Most fatal attacks by black bears, like this one, are the result of males hunting humans for food, according to a new study. ((Jonathan Hayward/Canadian Press))

"The predatory bears are silent and stalking a person and don't look like they are going to eat you alive, but that's what they will do if you don't deter them."

The study might debunk the idea that mother bears are the bigger danger in the wild, but it did confirm some other common beliefs: bears that have killed once are more likely to do it again, traveling with two or more people in the wilderness makes an attack much less likely, and human food and garbage attracts bears.

"The other thing that stands out is how rare these incidents are," he said. "This is two fatal attacks on average by black bears in all of Canada and the United States. Other things are far more dangerous."

While the rise in bear attacks has been correlated to the rise in the human population, fatal bear attacks are more common in Canada and Alaska, likely because bears are living in less productive food habitat with periodic food stress, Herrero said.

Herroro analyzed the information with the help of a graduate student and colleagues from Brigham Young University and employees at the Massachusetts Division of Fisheries and Wildlife.