Abstract
Evaluation of the impact of deer on natural forests requires a method that considers a variety of damage forms such as bark-stripping and browsing. Many individuals should be involved in the evaluation on a regional scale, and the method should be simple and objective. We conducted a survey using a simple check list of browsing scars and traces of deer. The check lists were completed by foresters of the district forest office, and 1,371 records were used for the analyses. The results of a multiple correspondence analysis (MCA) for 10 items suggested that each site could be plotted on a coordinate with three directions indicating that the impact was high, low, or unknown. The primary factors in the scoring of sites were correlated with sightings per unit effort (SPUE) by hunters. Many answers by foresters included the “Unknown” category for the existence of browsing scars and the abundance of less palatable plants. The number of replies where browsing scars were detected was lower for check lists completed by foresters than for those by the authors at the same sites, suggesting the under-recording by foresters. Estimation of the impact levels of deer on natural forests in Hokkaido by kriging the primary factor of MCA at each site was considered a valid technique, compared with existing information.
