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Replication of a 1970s Study on Domestic Sheep Losses to Predators on Utah’s Summer Rangelands
Author
Palmer, Brian C.
Conover, Michael R.
Frey, S. Nicole
Publisher
Society for Range Management
Publication Year
2010-11-01
Body

Lamb losses to predation have historically ranged from 4% to 8% in the western United States but most data are over 30 yr old. We repeated a sheep depredation study conducted from 1972 through 1975 on Cedar Mountain, Utah, to determine how predation rates have changed in the last three decades. Pastures and herd sizes were similar (1 730 lambs) between our study (2006 and 2007) and the prior one. Additionally, 40% of the ranchers in our study also participated in the prior study. During 2006 and 2007, 5.8% of all lambs on Cedar Mountain were lost to all causes compared to 9.5% during the 1970s. Predators were responsible for 87% of all verified lamb losses during our study versus 83% during the 1970s. We estimated that 4.9% of all lambs on Cedar Mountain were killed by predators during our study compared to 7.9% during the 1970s. During our study, coyotes (Canis latrans Say) were responsible for 67% of the depredated lambs, cougars (Felis concolor Linnaeus) for 31%, and black bears (Ursus americanus Pallas) for 2%. During the 1970s, coyotes killed 98% of all depredated lambs, cougars killed 2%, and bears killed 0%. In addition to the increase in cougar kills, the other change on Cedar Mountain since the 1970s is that California condors (Gymnogyps californianus Shaw) have begun scavenging lamb carcasses. Our results indicate that increasing populations of cougars, black bears, and condors have complicated the task of protecting lambs from predators.  The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020

Language
en
Resource Type
Text
Document Type
Journal Issue/Article
Digital Object Identifier (DOI)
10.2111/REM-D-09-00190.1
Additional Information
Palmer, B. C., Conover, M. R., & Frey, S. N. (2010). Replication of a 1970s study on domestic sheep losses to predators on Utah's summer rangelands. Rangeland Ecology & Management, 63(6), 689-695.
ISSN
0022-409X
OAI Identifier
oai:repository.arizona.edu:10150/642834
Journal Volume
63
Journal Number
6
Journal Pages
689-695
Collection
Rangeland Ecology & Management (REM)
Journal Name
Rangeland Ecology & Management
Keywords
black bears
Canis latrans
condors
cougars
coyotes
Felis concolor
Gymnogyps californianus
predation on lambs
sheep depredation
Ursus americanus