The study found that wolves living on the landscape with cattle have no effect on herd weight, but once a ranch has a confirmed wolf kill, average calf weight decreases relative to if that ranch had not experienced a wolf depredation.
“Ranchers have been saying for years that wolves cause weight loss in cattle, but nobody ever had done any research on the topic,” said Derek Kellenberg, a co-author on the study and UM associate professor and chair of the Department of Economics.
Kellenberg worked with UM Associate Professor Mark Hebblewhite from the Wildlife Biology Program and graduate students Joseph Ramler and Carolyn Sime. The Montana Department of Fish, Wildlife and Parks also cooperated on the study, which analyzed data from ranches in western Montana, including 15 years of records on ranch husbandry, satellite-generated climatological data, spatial data on wolf pack locations and confirmed depredations on 18 ranches.
The study quantifies the economic impact of weight loss after a confirmed wolf kill for an average ranch consisting of 264 head of calves. It finds that a decrease of 22 pounds in the average weight of calves across the herd implies a $6,679 loss at sale for an affected ranch.
“When you compare that to the direct reimbursement of the cow that was killed – about $900 on average – these indirect costs are about seven-and-a-half times the direct cost of depredation,” Kellenberg said.
The study notes that while the economic impact of lower herd weights caused by wolf depredation is not insignificant to ranchers, other ranch-specific husbandry practices and climatological and environmental variables such as annual precipitation, average temperature and snowfall explain a much larger proportion of variance in calf weight over the years than do wolf affects. In fact, these other factors explain the vast majority of the accounted-for variation in annual calf weights.
The study started as a senior thesis by then-undergraduate student Ramler, collecting data from public cattle auction records. When he decided to pursue a master’s in economics from UM, the group started collecting and analyzing data from a survey of individual western Montana ranchers.
Kellenberg hopes the study will help inform policymakers and ranchers as they work on issues related to wolf management.
“This study helps quantify some of the indirect costs that have not previously been accounted for,” he said.
The study was published Jan. 10 in the American Journal of Agricultural Economics and is titled “Crying Wolf? A Spatial Analysis of Wolf Location and Depredations on Calf Weight.” For more information visit http://www.cas.umt.edu/econ/, call Kellenberg at 406-243-5612 or email email@example.com
Derek Kellenberg | EurekAlert!
Kakao in Monokultur verträgt Trockenheit besser als Kakao in Mischsystemen
18.09.2017 | Georg-August-Universität Göttingen
Ultrasound sensors make forage harvesters more reliable
28.08.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine