Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sharks and wolves: Predator, prey interactions similar on land and in oceans

11.11.2010
There may be many similarities between the importance of large predators in marine and terrestrial environments, researchers concluded in a recent study, which examined the interactions between wolves and elk in the United States, as well as sharks and dugongs in Australia.

In each case, the major predators help control the populations of their prey, scientists said. But through what’s been called the “ecology of fear” they also affect the behavior of the prey, with ripple impacts on other aspects of the ecosystem and an ecological significance that goes far beyond these species.

The study was done by scientists from Oregon State University and the University of Washington, and was published in Frontiers in Ecology and the Environment, a professional journal.

“For too long we’ve looked at ecosystem functions on land and in the oceans as if they were completely separate,” said William Ripple, a professor in the Department of Forest Ecosystems at Society at OSU, and an international expert in the study of large predators such as wolves and cougars.

“We’re now finding that there are many more similarities between marine and terrestrial ecosystems than we’ve realized,” Ripple said. “We need to better understand these commonalities, and from them learn how interactions on land may be a predictor of what we will see in the oceans, and vice versa.”

In this study, Ripple and collaborator Aaron Wirsing, a researcher with the School of Forest Resources at the University of Washington, compared what has been learned about wolf and elk interaction in Yellowstone National Park in the U.S. to the interplay of tiger sharks and dugongs in Shark Bay, Australia. Dugongs are large marine mammals, similar to manatees, that feed primarily on seagrasses and are a common prey of sharks.

In studies with elk, scientists have found that the presence of wolves alters their behavior almost constantly, as they try to avoid encounters, leave room for escape and are constantly vigilant. The elk graze less in sensitive habitats, which in Yellowstone is helping streamside shrubs and aspen trees to recover, along with other positive impacts on beaver dams and wildlife.

Conceptually similar activities are taking place between sharks and dugongs, the researchers found. When sharks are abundant, dugongs graze less in shallow water where they are most vulnerable to sharks, and sacrifice food they might otherwise consume. This allows the seagrass meadows to thrive, along with the range of other plant and marine animal species that depend on them.

Related marine interactions have been observed in the North Atlantic Ocean, Ripple said. As shark populations were diminished by overfishing, the number of rays increased, which in turn reduced the level of sea scallops, an important fishery.

The marine/terrestrial similarities are also reflected in the body condition and health of species, the researchers noted. In Shark Bay, green sea turtles are more willing to face risks from sharks and seek the best grazing areas when their body condition is strong. In like fashion, the common wildebeest on the African Serengeti are less vulnerable to attack by lions or hyenas when their physical condition is good.

A more frequent information exchange between terrestrial and marine ecologists could provide additional insights into ecosystem function, the researchers said in their report.

About the OSU College of Forestry: For a century, the College of Forestry has been a world class center of teaching, learning and research. It offers graduate and undergraduate degree programs in sustaining ecosystems, managing forests and manufacturing wood products; conducts basic and applied research on the nature and use of forests; and operates 14,000 acres of college forests.

Bill Ripple | EurekAlert!
Further information:
http://www.oregonstate.edu

Further reports about: Forestry OSU Overfishing Ripple Shark Yellowstone ecosystem function shark populations

More articles from Studies and Analyses:

nachricht Real-time feedback helps save energy and water
08.02.2017 | Otto-Friedrich-Universität Bamberg

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>