30 Jul 2013:
Return of Yellowstone Wolves
Triggers Surge in Grizzly's Prized Berries
The reintroduction of wolves at Yellowstone National Park has caused a cascade of ecological effects that has led to the regrowth of berries
, an important food source for the park’s grizzly bears, scientists say. Writing in the Journal of Animal Ecology
, scientists from Oregon State University and the University of
Yellowstone National Park
Grizzly bear at Yellowstone Park
Washington report that the percentage of fruit found in bear scat has nearly doubled during the month of August in recent years. According to researchers, this reflects a recovery of berry bushes triggered in large part by the wolves, which have reduced overbrowsing by the park’s elk herds. “Wild fruit is typically an important part of grizzly bear diet, especially in late summer when they are trying to gain weight as rapidly as possible before winter hibernation,” said William Ripple, a professor at Oregon State University. The removal of wolves for most of the 20th century triggered the demise of the park’s young aspen and willow trees, as well as berry-producing shrubs, scientists say. According to the report, berries may be so important to the health of bear populations that their recovery could mean a lifting of the species’ “threatened” status under the Endangered Species Act
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 coral reefs, which are largely intact thanks to stifled coastal development in the communist nation. 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.