Elk harvest and the accessibility of hunt districts: does road density influence hunter harvest success?

Abstract

Wildlife managers are constantly faced with the difficulty of balancing growing demands for elk hunting opportunities and maintaining elk populations. Presence of roads and associated impacts to elk movements, behaviors, and vulnerability/mortality has been widely studied, with a general consensus of negative impacts to elk where roads are open to motorized use. Road density has also been shown to influence hunter densities and hunter effort which may indirectly effect harvest success. Previous studies analyzing elk harvest were limited to bull harvest only, certain hunting seasons, or lacked spatial replicates. The purpose of my study was to analyze road density and associated, all-inclusive harvest metrics on public land in 13 hunting districts of southwest Montana. Harvest was analyzed in two ways: estimated harvest number and harvest success (percentage successful hunters to total hunters). I obtained harvest reports for 2014 to 2016 data on hunter harvests. I used road data from the Forest Service, Bureau of Land Management, and Montana Department of Transportation, as well as public land GIS data from the state of Montana. GIS methods were conducted using QGIS. I conducted linear regression analyses to determine whether independent variables (road density, hunter density, hunter to elk ratios, hunter effort) were significant predictors on response variables (harvest number or success). Road density and hunter density were not significant predictors of harvest (number or percentage), while hunter effort and hunter to elk ratios were only significant predictors of harvest number. Road density on its own may not significantly predictor of harvest, but traffic on roads might. Hunter density was not directly linked to road density; therefore, it is unclear whether road density influenced hunter density and consequently harvest. One limitation was the lack of data for trails open to motorized use. Motorized route density may have been greater if open trails were included. Hunter effort and hunter to elk ratios may be useful to wildlife managers for predicting elk harvest numbers. If harvest numbers increase when these metrics increase, managers could implement changes to hunting in certain areas to increase hunter interest, therefore increasing hunters and potentially increasing harvest number.