Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Beware of predatory male black bears

11.05.2011
Research regarding North American black bear fatal attacks on people shows lone males are most dangerous, attack rates are rising with human population growth

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!
Further information:
http://www.ucalgary.ca

Further reports about: Herrero Wildlife bear attacks black bears population growth

More articles from Studies and Analyses:

nachricht Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung

nachricht Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>