Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Zebras vs. cattle: Not so black-and-white

23.09.2011
Grazing by wild animals like zebra doesn't always harm, and may help, livestock like cattle

African ranchers often prefer to keep wild grazers like zebras off the grass that fattens their cattle.

But a new study by Kenyan and University of California at Davis researchers shows that grazing by wild animals doesn't always harm, and may sometimes benefit, cattle.

The results are published in this week's issue of the journal Science.

"Although savanna rangelands worldwide are managed on the premise that cattle and wildlife compete for food, there is little scientific information to support this assumption," said Wilfred Odadi, a researcher at the Mpala Research Centre in Kenya and a co-author of the paper.

"When we look at the effect of wildlife on cattle, we find that they sometimes do suppress weight gain by cattle, but also sometimes enhance it," said Truman Young, a plant scientist at UC Davis and lead author of the paper.

"Generally the decision has been to exclude wild animals, but we're saying that things are not that simple," Young said.

"The finding that wildlife has a positive effect on cattle growth and production during times of plenty adds new insight into the role that facilitation plays in natural communities," said Saran Twombly, program director in the National Science Foundation's Division of Environmental Biology, which funded the research.

"Results from this study also speak directly to the critical importance of biodiversity in maintaining natural ecosystems," Twombly said.

The researchers enclosed 10-acre plots of savanna rangeland with fences to exclude wild animals--principally zebras.

Then they weighed the cattle grazing either with or without wild grazers to measure how much weight they put on at different times of the year, which is the bottom-line for ranchers.

Odadi and colleagues found that during the dry season, grazing by wild animals reduced weight gain by cattle, but in the wet season, cattle actually put on more weight when they grazed alongside wildlife.

The explanation is that during the wet season, grass can grow long and become rank, inaccessible and poor in nutritional value.

"When the grass grows very fast and is at risk of becoming rank, having zebras is beneficial," Young said. "They are more than willing to knock back the rank grass."

That means higher-quality, fresher grass for the cattle.

It's not yet clear whether there is a net benefit over a whole year or series of years, Young said, because conditions can vary considerably from year to year. Ranchers are beginning to explore additional ways to control rank grass, such as controlled burns.

"From a management perspective, the positive effect of wildlife on weight gain by cattle during the wet season suggests that wildlife conservation is not necessarily detrimental to, and can be compatible with, cattle production," Odadi said.

"Our findings provide further evidence that biodiversity conservation and economic development can be simultaneously achieved in human-occupied savanna landscapes."

Other co-authors of the paper are Moses Karachi, Egerton University, Kenya, and Shaukat Abdulrazak, National Council for Science and Technology, Nairobi, Kenya.

The work also was funded by the Smithsonian Institution, the National Geographic Society, the African Elephant Program of the U.S. Fish and Wildlife Service, and the International Foundation for Science.

Cheryl Dybas | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Ecology, The Environment and Conservation:

nachricht Scientists produce a new roadmap for guiding development & conservation in the Amazon
09.12.2016 | Wildlife Conservation Society

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>