A Tracking Technique to Locate Small Mammals at Low Densities

To optimize our livetrapping of low-density populations of lemmings (Dicrostonyx kilangmiutak) and voles (Microtus oeconomus) (0.2-0.4 animals/ha) in the Arctic tundra, we developed a powdered-slide tracking technique to determine if burrows were occupied. Painted microscope slides covered with talcum powder on a thin oil base were placed at all burrows on trapping grids, and only those burrows showing activity were trapped. Our capture success per trap tripled with this method in comparison with standard grid-stake trapping, and our effort per grid decreased by >50% after all burrows were initially located. This technique also should be useful in similar arid environments such as deserts, for obtaining relative indices of density, and for following toe-clipped animals.