Home Range Responses of White-tailed Deer to Crop-protection Fences

We studied the home ranges and activity patterns of 24 white-tailed deer (Odocoileus virginianus) in southwestern Wisconsin via radio-telemetry and visual observation to determine their response to single-strand electric crop-protection fences. Deer were allowed to establish feeding patterns in alfalfa fields during the spring green-up periods of 1986 and 1987. In mid-April of each year, 7 fences were constructed around selected 7-25 ha alfalfa fields to exclude deer from varying portions of their home ranges. No fences were constructed around alfalfa fields in one area. Fences were built around 50 and 100% of the alfalfa in 2 other areas. Deer movements were monitored in each of the 3 areas. Preliminary observations indicate that 1) marked and unmarked deer used alfalfa fields extensively from snowmelt to first cutting, 2) deer-use of alfalfa fields by deer decreased significantly (P<0.05) after fences were installed in the 50 and 100% treatment areas. Conversely, deer in the 0% treatment area significantly (P<0.05) increased their use of alfalfa fields after fences were installed, and 3) home ranges of deer in each of the treatment level areas decreased significantly (P<0.05) in size after fences were installed. Deer limited their movements primarily to nonalfalfa areas within their pre-fencing home ranges. These results lend further support for the use of fences in deer damage control. INTRODUCTION Crop damage caused by deer (Odocoileus spp.) has increased in many agricultural regions because of growing deer populations. In Wisconsin, the -* Department of Wildlife Ecology, University of WisconsinMadison, Madison, WI 53706. white-tailed deer herd (O_. virginianus) has increased to about 1 million and deer damage has been estimated at $36.7 million per year (Wisconsin Department of Agriculture, Trade and Consumer Protection 1984). Various types of deer fences have proven cost-effective in reducing deer damage in orchard, field and specialty crops (Palmer et al. 1985, Craven and Hygnstrom 1986). However, we do not know how deer respond when excluded from established feeding areas and other portions of their home ranges. Critics argue that excluded deer simply move to feed in fields that are unprotected, thereby making fencing a questionable alternative. The objectives of this study were to determine the effects of crop protection fences on home-ranges and activity of white-tailed deer so that conclusions could be made about the overall effectiveness of deer fencing. We thank our principle field assistants: K. A. Baker, J. j. Grimm, J. R. Hygnstrom, F. M. Lentsch, J. C. Melcher, C. A. Riebe and P. A. Terletzke. Research materials were provided by B. R. Bushweiler, 0. J. Rongstad, D. H. Rusch and J. Van Berkel. Computer and statistical assistance were provided by J. R. Cary and M. D. Samuel. The study was funded by the University of WisconsinMadison, College of Agriculture and Life Sciences and the Wisconsin Department of Natural Resources. Special thanks go to the Olin Arms Manufacturing Co. and the U. S. Dairy Forage Research Center for providing access to the study area. STUDY AREA The study was conducted at the Badger Army Ammunition Plant (BAAP) in southwestern Wisconsin. The BAAP is a 23km fenced enclosure consisting of mixed agricultural land,