MANAGING HABITAT FOR THE ENDANGERED STEPHENS KANGAROO RAT (DIPODOMYS-STEPHENSI) - EFFECTS OF SHRUB REMOVAL

To ascertain whether shrub removal enhances habitat suitability for St ephens' kangaroo rat (Dipodomys stephensi), we established five pairs of plots, each of which straddled a distinct boundary between coastal sage scrub and annual grassland habitats in western Riverside County, California. All aboveground portions of shrubs were removed from the s hrubby halves of one plot per pair in january 1991. Rodents were censu sed on all plots immediately before shrub removal and again after shru b removal in October 1991 and April 1992. Vegetation was censused in A pril 1992 to confirm that shrub removal had reduced shrub cover. Steph ens' kangaroo rat densities increased on removal plots after shrubs we re removed but decreased slightly on paired reference plots (treatment x time effect, P = 0.04). We conclude that shrub control should be a component of any habitat management plan for this endangered species.