Featured Research

from universities, journals, and other organizations

Raptor usurpers in neighboring habitats reshape the conventional wisdom

Date:
August 3, 2011
Source:
American Friends of Tel Aviv University
Summary:
Displaced indigenous species migrate to neighboring habitats that had not been included in environmental assessments, having a significant impact on the species and resources already there. New research from Israel suggests that researchers need to include these neighboring habitats in any responsible environmental survey.

Guilad Friedemann with a short-toed eagle in the Judean Foothills.
Credit: Image courtesy of American Friends of Tel Aviv University

When we make plans that will change a natural environment -- whether it's building a new shopping mall or planting a new forest -- surveyors dutifully assess the environmental risks to plant and animal life in the region. But what's environmentally good for one area may be an environmental disaster for an adjacent one, a Tel Aviv University researcher cautions.

When displaced by these projects, indigenous species migrate to neighboring habitats, says Guilad Friedemann, a PhD student at TAU's Department of Zoology in the George S. Wise Faculty of Life Sciences. This has a significant impact on the species and resources that were already there. With a new species moving in and demanding its share of existing space and food, competition becomes fierce.

Based on a study of two raptor species in the Judean Foothills, the long-legged buzzard and the short-toed eagle, Friedemann has determined that human interference in natural habitats has a reach beyond the specific region under assessment. Pursued under the supervision of TAU's Prof. Yossi Leshem and Prof. Ido Izhaki from the University of Haifa, and in collaboration with the KKL-JNF, Smolar -- Vinnikov Foundation, NPA and Kfar Etzion Field School, this ongoing research has been published in the journal Biological Conservation.

A turf war revealed by GPS

When a species is forced from its habitat, it has to go somewhere -- and that has an effect on neighboring environments. The long-legged buzzard had always made its home in the open spaces of the Judean Mountains, explains Friedemann, using the mountain cliffs for nesting and hunting. But because environmentalists have been planting a new forest in the area in a process known as "afforestation," the buzzard needed to migrate elsewhere. They now make their nests in the trees of the Judean Foothills, threatening the nesting ground and food source of the short-toed eagle, its established inhabitants.

Through extensive field research, including the placement of advanced GPS systems on the adult nesting birds, Friedemann and his fellow researchers tracked the movements of both species throughout breeding season by tagging four buzzards and three eagles. They found 31 buzzard nests and 60 eagle nests in the Judean Foothills. The researchers continue to examine each nest twice a season, tracking the growth of new chicks and analyzing food remains to determine the extent of competition for food sources between the two raptor species.

The results, say Friedemann, will indicate that the buzzards have started to muscle in on the eagles' habitat -- taking over their nests and diminishing the common food supply of snakes, lizards and rodents. "Every time you have strong competition between two species, one is more successful," he explains. "There is a negative impact on the weaker species."

The next step, says Friedemann, is to extend research done with the GPS transmitters, and to assess the rising levels of aggression in both buzzards and eagles, which arise from the heightened competition for food and space. By playing recorded bird calls near nesting sites of the opposite species, the researchers can measure how aggressive the response becomes.

Living side-by-side

In this case, afforestation, usually considered a positive contribution to the sustainability of our environment, was the cause of habitat destruction. This should serve as a cautionary lesson for any project that serves to alter the natural environment, the researchers conclude.

"There needs to be a broader consideration not just of the directly affected area, but of neighboring areas as well -- especially if there is a species that will be forced to abandon the original area and seek out a new place to live," Friedemann says. In this instance, harm might have been avoided by setting aside a track of open space where the buzzards could continue to nest and hunt, a conclusion that would have broad implications for landscape planning and policy.

We must take more responsibility for the assessment of neighboring habitats, Friedemann cautions, because what helps one environment might harm the next.


Story Source:

The above story is based on materials provided by American Friends of Tel Aviv University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Guilad Friedemann, Yoram Yom-Tov, Uzi Motro, Yossi Leshem. Shift in nesting ground of the long-legged buzzard (Buteo rufinus) in Judea, Israel – An effect of habitat change. Biological Conservation, 2011; 144 (1): 402 DOI: 10.1016/j.biocon.2010.09.018

Cite This Page:

American Friends of Tel Aviv University. "Raptor usurpers in neighboring habitats reshape the conventional wisdom." ScienceDaily. ScienceDaily, 3 August 2011. <www.sciencedaily.com/releases/2011/08/110803133551.htm>.
American Friends of Tel Aviv University. (2011, August 3). Raptor usurpers in neighboring habitats reshape the conventional wisdom. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2011/08/110803133551.htm
American Friends of Tel Aviv University. "Raptor usurpers in neighboring habitats reshape the conventional wisdom." ScienceDaily. www.sciencedaily.com/releases/2011/08/110803133551.htm (accessed July 22, 2014).

Share This




More Plants & Animals News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com
A Centuries' Old British Tradition Is Far from a Swan Song

A Centuries' Old British Tradition Is Far from a Swan Song

AFP (July 19, 2014) As if it weren't enough that the Queen is the Sovereign of the UK and 15 other Commonwealth realms, she is also the owner of all Britain's unmarked swans. Duration: 02:18 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins