text-only page produced automatically by LIFT Text Transcoder Skip all navigation and go to page contentSkip top navigation and go to directorate navigationSkip top navigation and go to page navigation
National Science Foundation
News
design element
News
News From the Field
For the News Media
Special Reports
Research Overviews
NSF-Wide Investments
Speeches & Lectures
NSF Current Newsletter
Multimedia Gallery
News Archive
News by Research Area
Arctic & Antarctic
Astronomy & Space
Biology
Chemistry & Materials
Computing
Earth & Environment
Education
Engineering
Mathematics
Nanoscience
People & Society
Physics
 

Email this pagePrint this page


Press Release 09-173
Invasive Species on the March: Variable Rates of Spread Set Current Limits to Predictability

Unknowns may place more species at risk in a changing climate

These red flour beetles are pictured on the wheat they eat and are often found near.

These red flour beetles are pictured on the wheat they eat and are often found near.
Credit and Larger Version

September 17, 2009

Whether for introduced muskrats in Europe or oak trees in the United Kingdom, zebra mussels in United States lakes or agricultural pests around the world, scientists have tried to find new ways of controlling invasive species by learning how these animals and plants take over in new environs.

In a paper published in this week's issue of the journal Science, biologists Brett Melbourne of the University of Colorado and Alan Hastings of the University of California at Davis report a previously unknown high variability in the rates of invasive species spread.

To reach their conclusions, they studied red flour beetles--beetles attracted to wheat flour--in experimental, enclosed landscapes with patches of habitat linked together.

They collected data from 30 landscapes composed of identical patches of land, all maintained under the same conditions, each initially home to 20 red flour beetles.

Although the landscapes were identical, there were considerable differences in how the beetles spread. By the end of the 13-beetle-generation experiment, the distance the beetles ranged spanned 10 to 31 "landscape patches."

"Scientists have struggled to understand why some species spread rapidly, while others don't," says Saran Twombly, acting deputy division director of the National Science Foundation (NSF)'s Division of Environmental Biology, which funded the research. "Once ecologists identified the key factors, it was thought, they could predict species spread with some certainty.

"Melbourne and Hastings have showed the opposite: intrinsic variability that could be random or have a genetic basis appears to have a large influence on species' spread. Researchers must now incorporate uncertainty in future approaches to 'ecological forecasting.'"

Everyone's familiar with uncertainty in weather forecasts, says Melbourne. "How often have we heard, 'there is a 75 percent chance of rain today?'"

As in weather systems, there's a degree of unpredictability in ecological systems.

The uncertainty arises because of randomness in both environmental and biological processes. "Ecologists have rarely measured it, however, so we haven't known how big it is," states Melbourne.

"We need to know more about how this affects the specific case of biological invasions," says Melbourne, "and how it changes ecosystem responses generally."

Ecologists will increasingly be called on to make the biological equivalent of weather forecasts: how will ecological systems respond to climate change, habitat destruction and loss of biodiversity?

Will species be able to migrate fast enough to keep pace with climate change?

Although more research is needed, the uncertainty Melbourne and Hastings found may place more species at risk in a changing climate: flora and fauna may not be able to march one step ahead of the pace of global warming.

-NSF-

Media Contacts
Cheryl Dybas, NSF, (703) 292-7734, cdybas@nsf.gov

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2014, its budget is $7.2 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

 Get News Updates by Email 

Useful NSF Web Sites:
NSF Home Page: http://www.nsf.gov
NSF News: http://www.nsf.gov/news/
For the News Media: http://www.nsf.gov/news/newsroom.jsp
Science and Engineering Statistics: http://www.nsf.gov/statistics/
Awards Searches: http://www.nsf.gov/awardsearch/

 

Scientists have studied red flour beetles to learn more about how invasive species spread.
Scientists have studied red flour beetles to learn more about how invasive species spread.
Credit and Larger Version



Email this pagePrint this page
Back to Top of page