Footprint Measurements

Abstract

Animal spoor or footprints per unit area can be used as an index of abundance (Van Dijke et al., 1986; Koster and Hart, 1988), while footprint measurements can be used to approximate the age-structure of an elephant population (Western et al., 1983), or to determine absolute density and distribution of elephant and black rhino (Kelly and Beer, 1994; Jachmann, 1984a), or large cats, such as lion, leopard and cheetah (Smallwood and Fitzhugh, 1993). Both elephants and rhinos are sufficiently heavy to render footprints visible for extended periods in a variety of soil types and habitats. When the population is small (< 40 individuals) and isolated (no migration), footprint measurements provide a means to identify individual animals. This technique may be combined with dropping measurements (circumference measurements of individual boli) to estimate abundance. Although the technique is relatively simple, leading to accurate estimates of abundance when used for small populations of solitary black rhino, its applicability for a gregarious species such as elephants is more complicated. Due to its limitations, the technique does not have a wide application in the field, but nevertheless may be useful under certain conditions. With only few small isolated pockets of black rhinos remaining in the wild, these conditions are found more frequently.