Do livestock guarding dogs lose their effectiveness over time?

Information about the effectiveness of livestock guarding dogs for reducing coyote predation on sheep was gathered from livestock producers in the Animal Damage Control Livestock Guarding Dog Program and in Colorado. Eighty-two percent of the producers contacted reported that the performance of their dogs remained the same or improved during 1993 compared with previous years. Eighteen percent of the producers reported a decrease in their dog's effectiveness, but most still felt the dogs were a benefit to their livestock operation. Most producers who noted a decrease in effectiveness attributed it to an apparent increase in the number of coyotes and/or an increase in their predatory activities on livestock