Spatial interactions among predators are central to their behavioral ecology. Although coyotes (Canis latrans Say, 1823), bobcats (Lynx rufus (Schreber, 1777)), and raccoons (Procyon lotor (L., 1758)) occur sympatrically throughout much of the USA, little is known about the nature of inter- and intra-specific spatial interactions. We used kernel analysis to estimate home ranges and core areas for these species. We estimated home-range overlap within and among species using the utilization distribution overlap index (UDOI) and percent overlap. Bobcat and coyote home ranges were similar in extent, whereas raccoons had substantially smaller home ranges. Only bobcats displayed seasonal differences in home-range size. Male bobcats had larger home ranges than female bobcats; there was no sex-based differentiation in home range or core area for coyotes or raccoons. Home-range overlaps calculated using percent overlap were consistently larger than UDOI estimates. Percent overlap seemed to exaggerate the extent to which individuals of the same species share space. Bobcats and coyotes shared space more than raccoons did with either bobcats or coyotes, which indicates that raccoons may have avoided areas used by trophically higher ranking mesopredators or that species with similar feeding strategies had lower levels of overlap to avoid competition.
A spoor count was done to determine whether caracal spoor densities in the vicinity of the border of the Kgalagadi Transfrontier Park differed from those in the interior of the Park. The objective was to compare caracal densities close to the agricultural land with those deeper in a national park. Two long-distance transects, one along the Namibian border and one diverging from the Namibian border into the interior of the Park, were surveyed on a monthly basis. Spoor density, discrete track set distances and orientation of spoor to the road were recorded and analysed to establish use patterns for three distinct zones in the Park. The hypothesis tested was that increased spoor counts along the border should result from an attraction to the adjacent agricultural (cattle and sheep production) land. It is shown that caracals avoid the areas near the Namibian border during the hot season but increased their utilization in this region in the cold season. This implies that under conditions of low prey availability (cold season) caracals may move to the border and cross onto agricultural land to prey on small livestock, there.
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