Track counts as indices to abundances of arboreal rodents.

Abstract

Counting tracks to obtain an index of abundance for species difficult to capture offers a promise of efficiency and effectiveness when broad surveys of populations are necessary. Sand plots, smoked kymograph paper, and, recently, smoked aluminum plates have been used to record tracks(Raphael et al., 1986; Taylor and Raphael, 1988). Findings of studies of carnivores conducted by using smoked-aluminum track-plates suggest the technique might prove useful for study of arboreal rodents, especially northern flying squirrels, Glaucomys sabrinus (Raphael et al., 1986). Raphael et al. (1986) reported patterns of abundance of flying squirrels based on track-plate surveys and recommended track plates for that purpose. We tried unsuccessfully to calibrate a track index to densities of flying squirrels and Townsend’s chipmunks (Tamias townsendii), as determined by live trapping, and abundance of Douglas' squirrels (Tamiasciurus douglasii), as determined from point counts of calls. Although the techniques are not directly comparable, rank orders of abundance derived from live trapping and point counts (direct observations of individual animals) can be contrasted with rank orders derived from track counts (observation of sign). We report those results here.

Citation

Carey, A.B.; Witt, J.W. 1991.. Track counts as indices to abundances of arboreal rodents. Journal of Mammology. 72(1): 192-194