02 May 2012:
Polar Bears Taking Long Swims
In Absence of Summer Sea Ice, Study Says
A six-year study has found that polar bears are capable of swimming great distances
when foraging for food, an increasingly critical skill as Arctic sea ice declines in summer. Using GPS collars attached to 52
adult females in the southern Beaufort and Chukchi seas from 2004 to 2009, scientists from the U.S. Geological Survey (USGS) found that about a third of the bears — including some with cubs — completed swims greater than 30 miles. Writing in the Canadian Journal of Zoology
, the scientists found that in the case of 50 long-distance swims, the bears traveled an average of 96 miles, swimming from one to 10 days; one bear swam 220 miles. While such stamina will become increasingly important for polar bears as a warming climate makes resting on summer sea ice a less available option, the researchers expressed concern that traveling such great distances takes a greater energy toll on the animals. The study sample was too small to draw conclusions about the fate of entire populations, and it is unclear whether such long swims are a new behavior. “These long distances of open water didn’t use to exist in the southern Beaufort Sea,” Karen Oakley, a USGS biologist told Reuters
. “Did they swim these really long distances? Well, they didn’t have to because they weren’t there.”
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
Photographer Robert Wintner documents the exquisite beauty and biodiversity of Cuba’s unspoiled coral reefs. View the gallery.
is now available for mobile devices at e360.yale.edu/mobile
The Warriors of Qiugang
, a Yale Environment 360
video, chronicles a Chinese village’s fight against a polluting chemical plant. It was nominated for a 2011 Academy Award for Best Documentary Short.
Watch the video.
Top Image: aerial view of Iceland
. © Google & TerraMetrics.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.