As western states debate removing the gray wolf from protection under the Endangered Species Act, a new study by the Wildlife Conservation Society cautions that doing so may result in an unintended decline in another species: the pronghorn, a uniquely North American animal that resembles an African antelope.
The study, appearing in the latest issue of the journal Ecology, says that fewer wolves mean more coyotes, which can prey heavily on pronghorn fawns if the delicate balance between predators and their prey is altered. According to the study, healthy wolf packs keep coyote numbers in check, while rarely feeding on pronghorn fawns themselves. As a result, fawns have higher survival rates when wolves are present in an ecosystem.
“People tend to think that more wolves always mean fewer prey,” said WCS researcher Dr. Kim Berger, lead author of the study. “But in this case, wolves are so much bigger than coyotes that it doesn’t make sense for them to waste time searching for pronghorn fawns. It would be like trying to feed an entire family on a single Big Mac.”
Over a three-year period, researchers radio-collared more than 100 fawns in wolf-free and wolf-abundant areas of Grand Teton National Park and monitored their survival throughout the summer. The results showed that only 10 percent of fawns survived in areas lacking wolves, but where coyote densities were higher. In areas where wolves were abundant, 34 percent of pronghorn fawns survived. Wolves reduce coyote numbers by killing them outright or by causing them to shift to safer areas of the Park not utilized by wolves.
While pronghorn are not endangered, the population that summers in Grand Teton National Park, part of the Greater Yellowstone Ecosystem, had been reduced to fewer than 200 animals in recent years. Since wolves were reintroduced in 1995, the pronghorn population in Grand Teton has increased by approximately 50 percent. These pronghorn have the longest migration – more than 200 miles roundtrip – of any land mammal in the lower 48 states. The Wildlife Conservation Society has called for permanent protection of their migration corridor, known as “Path of the Pronghorn,” to prevent the animals from going extinct in the Park. Representatives from the National Park Service, U.S. Fish and Wildlife Service, and U.S. Forest Service recently pledged support for protecting the corridor.
If delisting occurs, Wyoming and Idaho have announced their intention to reduce wolf number by 50percent and 80 percent, respectively. At present, there are an estimated 300 wolves in Wyoming and 700 in Idaho.
“This study shows just how complex relationships between predators and their prey can be,” said Berger. “It’s an important reminder that we often don’t understand ecosystems nearly as well as we think we do, and that our efforts to manipulate them can have unexpected consequences.”
Stephen Sautner | EurekAlert!
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Materials Sciences
23.03.2018 | Agricultural and Forestry Science
23.03.2018 | Physics and Astronomy