Predators can affect how livestock watch over their young

Rangeland Ecology & Management and Society for Range Management

Wheat Ridge, Colo. — Livestock are likely to spend more time on the lookout for predators soon after the loss of a calf and, therefore, have less time to forage for their food, according to a new study. Consequently, predators such as wolves, mountain lions, and coyotes can affect the economic solvency of livestock producers, according to an article in the May 2008 issue of Rangeland Ecology and Management, published by the Society for Range Management.

"Our results show that vigilance behavior in cattle is plastic," write Bryan M. Kluever, Stewart W. Breck, Larry D. Howery, Paul R. Krausman, and David L. Bergman in their article "Vigilance in Cattle: The Influence of Predation, Social Interactions, and Environmental Factors."

In the article, they outline their findings after observing cattle during peak foraging hours for two summers in northeast Arizona. During this time, the researchers watched how predators affected the scanning behavior, or vigilance, of cattle. They found that factors affecting vigilance and foraging behavior include lactation status, herd size, and visual obstructions.

In the first three days after the loss of a calf, mother cows had higher vigilance rates but spent less time on foraging. However, within 10 days of the calf death, their vigilance and foraging times returned to earlier levels.

Cattle have lower vigilance rates than wild ungulates, the researchers say, likely because of the domestication process. However, they "react to predators in a similar fashion to wild ungulates," the authors write.

The type of predator also may affect vigilance levels, the researchers say. Cattle may be more wary of chasing or harassing predators than those who stalk or ambush their prey. "Understanding these differences could be important for livestock management practices," the researchers write.

To read the entire study, "Vigilance in Cattle: The Influence of Predation, Social Interactions, and Environmental Factors," click here: http://www.allenpress.com/pdf/RAMA-61.3.pdf