15 Mar 2012:
Unusual Pine Beetle Breeding
Could Explain Tree Epidemic, Study Says
A new study has found that some populations of mountain pine beetles are producing two generations of tree-killing offspring each year
, a phenomenon that may help explain the scale of damage being done to
vast tracts of lodgepole and ponderosa pines across western North America. After observing beetle behavior during the summer months, scientists from the University of Colorado, Boulder, were surprised to see that some beetles that had been hatched just two months earlier were already attacking trees. Typically the mountain pine beetles spend a winter as larvae within the trees before emerging as adults the following summer. According to the researchers, this extra generation could produce 60 times as many beetles devouring trees in a given year. Since the late-1990s, oubreaks of the mountain pine beetles — linked to warmer winters
— have devastated more than 70,000 square miles of forest in western Canada and the U.S., the largest known outbreak in history. “This thing is immense,” said Jeffry Mitton, a CU-Boulder professor of ecology and evolutionary biology and lead author of the study published in The American Naturalist
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
The 2015 Yale e360 Video Contest winner documents a Northeastern town's bitter battle over a wind farm. Watch the video.
is now available for mobile devices at e360.yale.edu/mobile
A 2015 Yale e360 Video Contest winner captures stunning images of wild salmon runs in Alaska. Watch the video.
video goes onto the front lines with Colorado firefighters confronting deadly blazes fueled by a hotter, drier climate. Watch the video.
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.
Top Image: aerial view of Iceland
. © Google & TerraMetrics.