The traditional means of tracking animal location in a field is by visual observation. Not only is this method labor intensive, it is also prone to error as the observer can alter cattle movement, observation periods are often too short to obtain confidence in general daily behavior patterns, and observer fatigue becomes an issue. In the 1990s, the University of Kentucky began using GPS collars on cattle to track their position with the goal of incorporating this information into cattle management practices. One of the key unanswered questions regarding the GPS collars is the accuracy of the position data recorded by the collar. The objective of this work was to assess the capabilities and limitations of using GPS collars to track animal movement in grazed watersheds. Static tests were conducted in an open field, under trees, and near fence lines to ascertain the impacts of various field features on collar performance. Dynamic tests were carried out to examine the errors associated with the collars while operated under real-world conditions. Results from these tests indicate that the collars generally provide data with horizontal accuracies of 4 to 5 m. This information will assist researchers in the development of experiments based on collar capabilities and limitations.

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Notes/Citation Information

Published in Transactions of the ASAE, v. 47, issue 4, p. 1321-1329.

© 2004 American Society of Agricultural Engineers

The copyright holder has granted the permission for posting the article here.

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Funding Information

A USDA Integrated Research, Education, and Extension Section 406 grant provided funding for the GPS collars used in the ongoing intensive grazing research project at the University of Kentucky’s Animal Research Center. A Kentucky Senate Bill 271 grant and a SARE Graduate Student Award provided additional funding.