Fatal encounters with black bears have been exceedingly rare during the last century, but appear to be mainly the result of predatory male bears targeting humans in their wilderness home ranges, according to a new study led by the world's leading expert on bear attacks.
In an article published today in the Journal of Wildlife Management, University of Calgary professor emeritus Dr. Stephen Herrero, University of Calgary graduate Andrew Higgins, and colleagues from the Massachusetts Division of Fisheries and Wildlife and Brigham Young University analyzed the circumstances of all recorded deaths inflicted by non-captive black bears in North America between 1900 and 2009. The study found that 63 people were killed in 59 incidents in Canada, Alaska and the lower 48 states. The researchers determined that the majority (88%) of fatal attacks involved a bear exhibiting predatory behaviour, and 92% of the predatory bears were males. The authors suggest male black bears have evolved some different behaviours than females.
"Each year there are millions of interactions between people and black bears with no injuries to people. So while the risk is low, it does exist," said Herrero, an expert in bear behaviour and ecology in the U of C's Faculty of Environmental Design. "Our findings raise some important new insights that can be used to better understand the cause of attacks and how they can be avoided in both the front and backcountry."
In particular, the common belief that surprising a mother bear with cubs is the most dangerous kind of black bear encounter is inaccurate. Instead, lone male black bears hunting people as a potential source of food are a greater cause of deadly maulings and related predatory attempts. The study also found that fatal attacks do not typically involve bears that are familiar with humans, although some fatal attacks did.
"Most fatal black bear attacks were predatory and all fatal attacks were carried out by a single bear," Herrero said. "With training, people can learn to recognize the behaviour of a bear that is considering them as prey and deter an attack by taking aggressive action such as fighting back."
The paper confirms other current perceptions and bear management practices. It found that bears that have previously killed people are more likely to attack again; parties of more than two people are much less likely to be attacked; and human food and garbage tends to attract bears and may increase the likelihood of serious bear attacks.
Examining 110 years of data also allowed the researchers to identify historical and geographic trends of black bear attacks. They found that 86% of fatal attacks occurred since 1960; that fatalities are more common in Canada and Alaska despite lower human populations and less contact between humans and bears than in the lower 48 states; and that human population growth is accompanied by rising fatal bear attacks.
"We didn't demonstrate why population growth is correlated with more bear attacks but we suspect it is because there are more people pursuing recreational and commercial activities in black bear habitat," Herrero said. "Similarly, we don't know exactly why there have been more attacks in Canada and Alaska, but we speculate that it could be because bears in those areas are living in less productive habitat with periodic food stress, which may predispose some bears to consider people as prey."
The article "Fatal Attacks by American Black Bear on People: 1900-2009" by Stephen Herrero, Andrew Higgins, James E. Cardoza, Laura I. Hajduk & Tom S. Smith is published in the April, 2011 issue of the Journal of Wildlife Management.
Grady Semmens | EurekAlert!
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
22.05.2018 | Life Sciences
22.05.2018 | Earth Sciences
22.05.2018 | Trade Fair News