Navigation Links
Polar bears can't eat geese into extinction
Date:11/4/2010

As the Arctic warms, a new cache of resourcessnow goose eggsmay 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."


'/>"/>

Contact: Kristin Phillips
kphillips@amnh.org
212-496-3419
American Museum of Natural History
Source:Eurekalert  

Related biology news :

1. Study of polar dinosaur migration questions whether dinosaurs were truly the first great migrators
2. Polarized light guides cholera-carrying midges that contaminate water supplies
3. Bipolar disorder genes, pathways identified by Indiana University neuroscientists
4. Goose eggs may help polar bears weather climate change
5. Polarstern expedition LOHAFEX can be conducted
6. Polar research reveals new evidence of global environmental change
7. Research plane Polar 5 on Arctic campaign
8. New light on bipolar treatment drugs
9. Research vessel Polarstern starts 24th Arctic season
10. New tracking approach will help protect polar bears
11. ESHRE launches international study of polar body screening
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Polar bears can't eat geese into extinction
(Date:3/23/2016)... March 23, 2016 ... Sicherheit Gesichts- und Stimmerkennung mit Passwörtern ... (NASDAQ: MESG ), ein führender Anbieter ... Unternehmen mit SpeechPro zusammenarbeitet, um erstmals dessen ... wird die Möglichkeit angeboten, im Rahmen mobiler ...
(Date:3/18/2016)... 2016 --> --> ... Manned & Unmanned Vehicles, Physical infrastructure and Perimeter Surveillance & ... the border security market and the continuing migration crisis in ... Europe has led visiongain to publish this unique ... --> defence & security companies in the border ...
(Date:3/14/2016)... March 14, 2016 NXTD ) ("NXT-ID" ... commerce market, announces the airing of a new series of ... week of March 21 st .  The commercials will air ... popular Squawk on the Street show. --> NXTD ... growing mobile commerce market, announces the airing of a new ...
Breaking Biology News(10 mins):
(Date:5/20/2016)... , ... May 20, 2016 , ... The leading Regenerative ... its most experienced veterinary clients have treated over 100 of their own patients with ... to provide the highest level of care for their patients. , The veterinarians ...
(Date:5/19/2016)... ... May 19, 2016 , ... Anton Paar USA, located in Ashland, ... building is complete. The new structure adds a third office building to the current ... purchased 2.4 acres of land, along with office space adjacent to the previous ...
(Date:5/19/2016)... May 19, 2016 ... (OTC PINK: RGBPP) announced today initiation of a ... cord blood based cancer immunotherapeutic product leveraging its ... Regen described a generation of cord blood derived ... gene silencing.  The product in development will be ...
(Date:5/18/2016)... May 18, 2016 The Biotech industry ... not mean that there are no opportunities ahead. Today, ActiveWallSt.com ... (NASDAQ: THLD ), Seattle Genetics Inc. (NASDAQ: ... and Ophthotech Corp. (NASDAQ: OPHT ). Sign up ... http://www.activewallst.com/ Threshold Pharmaceuticals Inc.,s ...
Breaking Biology Technology: