An assesment of a technique for computer-assisted habitat evaluation for bobwhite quail on Ames Plantation

The efficacy of a computer-assisted system of habitat evalua-tion [IMGRID (Information Management on a GRID cell system)] was tested on the Ames Plantation in west Tennessee. Habitat and census data were analyzed to examine the extent and effect of land use changes between 1965 and 1980. Significant changes in land use occurred. Pastures decreased from 120.4 ha in 1966 to 35.0 ha in 1980, while soybeans increased from 102.4 ha to 193.1 ha. Idle land decreased from 212.9 ha to 178.6 ha between 1966 and 1980. High correlation was found between fluctuations in bobwhite (Colinus virginianus) populations and changes in the area maintained in soybeans (r = -0.63), pastures (r = 0.76) and idle land (r = 0.76). Quality bobwhite habitat has probably been reduced by the transferral of idle land and lightly grazed pasture to large expanses of soybeans. Each habitat type's percentage of utilization by bobwhites during censuses was calculated for 1966, 1971, 1975 and 1980 using two techniques, the multiple component and the single component analyses. Multiple component analyses delineated highest utilization in areas where idle land, forests and agriculture came within close proximity, in areas near food plots and in idle land alone. The single component analyses found high utilization of idle land, wild herbaceous vegeta-tion and food plots. Areas containing honeysuckle within forests or idle land were also preferred by bobwhites. IMGRID successfully detected changes in land use and trends in habitat utilization. However, manual techniques could achieve similar results. Due to continuing costs and comparable manual management techniques, IMGRID will only be justified in the future if additional habitat research is conducted using it as a tool.