(Press-News.org) As the Arctic warms, a new cache of resources—snow goose eggs—may help sustain the polar bear population for the foreseeable future. In a new study published in an early online edition of Oikos, researchers affiliated with the Museum show that even large numbers of hungry bears repeatedly raiding nests over many years would have a difficult time eliminating all of the geese because of a mismatch in the timing of bear arrival on shore and goose egg incubation.
"There have been statements in popular literature indicating that polar bears can extirpate snow geese quickly once they start to eat eggs," says Robert Rockwell, a research associate in the Division of Vertebrate Zoology at the Museum and a professor at the City University of New York. "However, there will always be the occasional mismatch in the overlap between the onshore arrival of bears and the incubation period of the geese. Even if the bears eat every egg during each year of complete 'match,' our model shows that periodic years of mismatch will provide windows of successful goose reproduction that will partially offset predation effects."
In the last few years, work along the Cape Churchill Peninsula of western Hudson Bay by Rockwell and colleagues has suggested that polar bears are not as hamstrung by their environment as many biologists believe. One new nutritional option for polar bears is the bounty of goose eggs which had previously hatched into goslings that were gone by the time bears came ashore. In recent years, 'early' bears have left breaking sea ice to come ashore and consume eggs. In fact, the earlier the bears come ashore, the better: eggs are higher in nutrients when the embryo is younger.
In the new Oikos paper, Rockwell and coauthors Linda Gormezano (also affiliated with the Museum) and David Koons (a researcher at Utah State University in Logan) simulated the timing of events during the Arctic spring: the break-up of sea ice, the movement of bears onto shore, the migration of geese to the North, and the laying of eggs. Results from the computer model show that the mismatch of timing is something that both the bears and geese can use to their advantage. The timing of geese migration is primarily based on photoperiod (the amount of light in 24 hours), which will not change as quickly as polar bear movements, which are based on the melting of sea ice.
Results show that the advance in mean overlap of the two species gives an advantage to polar bears. But increased variability, also the result of global climate change, leads to an increased mismatch that is good news for snow geese.
"Mismatch is often thought to be bad, but in this case periodic mismatch is good because it keeps geese from going extinct and allows polar bears to eat," says Rockwell. "Are polar bears adaptable? Of course. This could be a nice stable system. The geese aren't going to go away, and they are a nutrient resource for the bears."
INFORMATION:
The research for this paper was supported by the Hudson Bay Project.
Polar bears can't eat geese into extinction
New statistical model demonstrates that trophic mismatch feeds bears without exterminating snow geese
2010-11-05
ELSE PRESS RELEASES FROM THIS DATE:
Pigs reveal secrets: New research shines light on Quebec industry
2010-11-05
Which are the best pieces of pork, what their texture is, how moist they are – the secrets pigs keep from even the most skilled butchers – are about to be revealed, thanks to a sophisticated new technique that has been developed by McGill University researchers in conjunction with Agriculture Canada and the pork industry. "This is about giving industry workers better tools to do their job," explained Dr. Michael Ngadi of McGill's Department of Bioresource Engineering. "Computer-aided analysis of meat will result in higher-quality jobs, optimal production, and exports that ...
Hard work improves the taste of food, Johns Hopkins study shows
2010-11-05
It's commonly accepted that we appreciate something more if we have to work hard to get it, and a Johns Hopkins University study bears that out, at least when it comes to food.
The study seems to suggest that hard work can even enhance our appreciation for fare we might not favor, such as the low-fat, low calorie variety. At least in theory, this means that if we had to navigate an obstacle course to get to a plate of baby carrots, we might come to prefer those crunchy crudités over the sweet, gooey Snickers bars or Peanut M&Ms more easily accessible via the office vending ...
Burning pain and itching governed by same nerve cells
2010-11-05
There are disorders and conditions that entail increased itching and can be extremely troublesome for those suffering from it. The mechanisms behind itching are not well understood today. For one thing, what is it about scratching that relieves itching?
In the current study, which was performed on mice, the research team led by Professor Klas Kullander at the Department of Neuroscience examined the nerve cells that transfer heat pain. When these nerve cells had lost its capacity to signal, the mice reacted less to heat, as expected, but surprisingly they also started ...
UMD-led deep impact spacecraft successfully flies by comet Hartley 2
2010-11-05
COLLEGE PARK, Md. – The University of Maryland-led EPOXI mission successfully flew by comet Hartley 2 at 10 a.m. EDT today, and the spacecraft has begun returning images. Hartley 2 is the fifth comet nucleus visited by any spacecraft and the second one visited by the Deep Impact spacecraft.
Scientists and mission controllers are studying never-before-seen images of Hartley 2 appearing on their computer terminal screens. See images at: http://epoxi.umd.edu/
"We are all holding our breath to see what discoveries await us in the observations near closest approach," said ...
Researchers unlock the secret of bacteria's immune system
2010-11-05
Quebec City, November 4, 2010—A team of Université Laval and Danisco researchers has just unlocked the secret of bacteria's immune system. The details of the discovery, which may eventually make it possible to prevent certain bacteria from developing resistance to antibiotics, are presented in today's issue of the scientific journal Nature.
The team led by Professor Sylvain Moineau of Université Laval's Department of Biochemistry, Microbiology, and Bioinformatics showed that this mechanism, called CRISPR/Cas, works by selecting foreign DNA segments and inserting them ...
A 'brand' new world: Attachment runs thicker than money
2010-11-05
Can you forge an emotional bond with a brand so strong that, if forced to buy a competitor's product, you suffer separation anxiety? According to a new study from the USC Marshall School of Business, the answer is yes. In fact, that bond can be strong enough that consumers are willing to sacrifice time, money, energy and reputation to maintain their attachment to that brand.
"Brand Attachment and Brand Attitude Strength: Conceptual and Empirical Differentiation of Two Critical Brand Equity Drivers," a study published in the November issue of the Journal of Marketing, ...
X-rays offer first detailed look at hotspots for calcium-related disease
2010-11-05
Menlo Park, Calif.—Calcium regulates many critical processes within the body, including muscle contraction, the heartbeat, and the release of hormones. But too much calcium can be a bad thing. In excess, it can lead to a host of diseases, such as severe muscle weakness, a fatal reaction to anesthesia or sudden cardiac death.
Now, using intense X-rays from the Stanford Synchrotron Radiation Lightsource (SSRL) at the Department of Energy's SLAC National Accelerator Laboratory, researchers have determined the detailed structure of a key part of the ryanodine receptor, a ...
Colonic navigation
2010-11-05
Nanoparticles could help smuggle drugs into the gut, according to a study published this month in the International Journal of Nanotechnology.
There are several drugs that would have more beneficial therapeutic effects if they could be targeted at absorption by the lower intestine. However, in order to target the colon for treating colon cancer for instance, medication delivered by mouth must surmount several barriers including stomach acidity, binding to mucus layers, rapid clearance from the gut, and premature uptake by cells higher up the gastrointestinal tract. Being ...
Helical CT scans reduce lung cancer mortality by 20 percent compared to chest X-rays
2010-11-05
PROVIDENCE, R.I. [Brown University] — In a major new study announced today by the National Cancer Institute, researchers including Brown University biostatistian Constantine Gatsonis and his colleagues found that screening for lung cancer using helical CT scanning reduced lung cancer deaths by 20 percent compared to using chest X-rays.
"The findings we're announcing today offer the first definitive evidence for the effectiveness of helical CT screening smokers for lung cancer " said Gatsonis, a lead biostatistician in the study and director of the American College of ...
Motor Neurone Disease Association study identifies MND biomarker
2010-11-05
A study funded by the Motor Neurone Disease (MND) Association, in collaboration with the Medical Research Council (MRC), has identified a common signature of nerve damage in the brains of MND patients.
The study's exciting findings have been published in the prestigious journal Neurology (2 November 2010). These are the first results to be published from the ongoing Oxford Study for Biomarkers in MND/ALS (BioMOx).
MND research is being held back by the lack of an early diagnostic test and predictable markers of the progression of the disease – biomarkers. Patients ...
LAST 30 PRESS RELEASES:
Deaf male mosquitoes don’t mate
Recognizing traumatic brain injury as a chronic condition fosters better care over the survivor’s lifetime
SwRI’s Dr. James Walker receives Distinguished Scientist Award from Hypervelocity Impact Society
A mother’s health problems pose a risk to her children
Ensuring a bright future for diamond electronics and sensors
The American Pediatric Society selects Dr. Maria Trent as the Recipient of the 2025 David G. Nichols Health Equity Award
The first 3D view of the formation and evolution of globular clusters
Towards a hydrogen-powered future: highly sensitive hydrogen detection system
Scanning synaptic receptors: A game-changer for understanding psychiatric disorders
High-quality nanomechanical resonators with built-in piezoelectricity
ERC Synergy Grants for 57 teams tackling major scientific challenges
Nordic research team receives €13 million to explore medieval book culture
The origin of writing in Mesopotamia is tied to designs engraved on ancient cylinder seals
Explaining science through dance
Pioneering neuroendocrinologist's century of discovery launches major scientific tribute series
Gendered bilingualism in post-colonial Korea
Structural safety monitoring of buildings with color variations
Bio-based fibers could pose greater threat to the environment than conventional plastics
Bacteria breakthrough could accelerate mosquito control schemes
Argonne to help drive AI revolution in astronomy with new institute led by Northwestern University
Medicaid funding for addiction treatment hasn’t curbed overdose deaths
UVA co-leads $2.9 million NIH investigation into where systems may fail people with disabilities
With the help of AI, UC Berkeley researchers confirm Hollywood is getting more diverse
Weight loss interventions associated with improvements in several symptoms of PCOS
Federal government may be overpaying for veterans’ health care in Medicare Advantage plans
Researchers awarded $2.5 million grant to increase lung cancer screenings in underserved communities
New trigger proposed for record-smashing 2022 Tonga eruption
Lupus Research Alliance announces Lupus Research Highlights at ACR Convergence 2024
Satellite imagery may help protect coastal forests from climate change
The secrets of baseball's magic mud
[Press-News.org] Polar bears can't eat geese into extinctionNew statistical model demonstrates that trophic mismatch feeds bears without exterminating snow geese