Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Grizzly bears feast on diverse diet

16.02.2007
There’s no such thing as picky grizzly bears—they’ll eat almost anything they can find. A new University of Alberta study that tracked food habits of the Alberta grizzly bear living in the foothills sheds some light on the animal’s varied diet and their activity pattern.

“Alberta bears have remarkably diverse diets,” said Dr. Mark Boyce, biological sciences professor at the U of A and co-author on the study. “They’ll eat just about anything.”

Ants, fruits, moose and plants are a few staples of the Alberta grizzly bear’s diet. This new research study was the most comprehensive examination of grizzly bear foods ever conducted in Canada. Using global positioning system (GPS) radiotelemetry technology and analyzing 665 feces collected from 18 grizzly bears over a period of three years, the scientists found that the bears packed a lot of activity into 24 hours. The research was recently published in the “Journal of Mammalogy.”

Much is known about what bears in mountainous areas eat but little is known of the diets of grizzly bears living in boreal forests also used by humans. As well, this new research looked at five different activities the bears use to find food—whether it feeds on flowers, insects, fruits, digs for plants or kills other animals, specifically ungulates.

The diverse diets of the Alberta grizzly bear helps cushion them against climate change and other vagaries of the environment, said Boyce. Specifically, the research team found that the bears living in the foothills are effective predators on moose and deer. They are especially good at killing moose calves during the difficult spring period when other foods like berries are not yet available, said Boyce. Mountain bears are largely vegetarian, by comparison.

The scientists identified 40 different food items, examining each for seasonal patterns of use and differences among mountain and foothills environments. Digging the root of sweet vetch plants dominated early spring diets, while preying on ungulates—or hooved animals--was greatest during late spring, although the timing varied between foothill and mountain bears. Moose were the most common ungulate eaten by the bear (83 per cent), especially newborns (54 per cent), with white-tailed and mule deer (16 per cent) and elk (1 per cent) more minor in comparison. Rodents, insects (primarily ants), and birds were also consumed. Green vegetation dominated early summer diets and as fruit ripened in early August, berries such as soopolallie and mountain huckleberry were added to the bears’ menu. The scientists also learned that most of the activity of the east slopes bears takes place in the daytime, especially morning and the evening. This is in contrast to bears living in spots where more frequent contact with humans take place, such as Banff National Park where most bear activity has become nocturnal.

Although the bears are filling up on these different food sources, being so near to highways and roads is dangerous for the animals.

“Bears are eating substantial amounts of clover and alfalfa, which are common roadside plantings,” said Boyce. “Because these roadside plantings are attractive to bears, this can put the bears at risk of contact with humans. Nearly all new roads being constructed in the province are built by industry, either for timber harvest or oil and gas development.

“We should encourage industry to avoid using such attractive food items when planting in ditches and roadsides. It would be much better to use native grasses and other native plants to stabilize road banks and ditches. Most bear deaths occur near roads and we want to avoid attracting bears to areas near roads.”

Phoebe Dey | EurekAlert!
Further information:
http://www.ualberta.ca

More articles from Ecology, The Environment and Conservation:

nachricht How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>