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We systematically collected Coyote scats along 10 8-km routes, first in April and again in July. Routes were located along roads and trails, were at least 1.6 km apart, and were distributed throughout the study area. We cleared routes of all scats two weeks prior to each collection. We collected all Coyote scats along each route, and plotted their locations on a map to estimate the minimum number of Coyote family units sampled. We buffered around each scat location with a radius of 4.52 km, which represents the diameter of the average home range size of a Coyote family unit during spring and summer (Gese et al. 1988b). Buffer zones that overlapped were considered to represent the same Coyote family-unit home range.

All scats were stored frozen and later oven-dried for 48 hours at 70°C (Corbett 1989). Dry weights were recorded for all samples. The contents of each scat were washed separately with water through a 36 mesh/cm² sieve and residues were air dried, similar to methods of Greenwood (1981). We identified residues to the lowest taxon possible on the basis of hair, plant material, teeth, feathers and exoskeletal parts. Hair was identified primarily by micro structure (Moore et al. 1974). Seeds and teeth were identified by using reference collections and manuals (Schwartz and Schwartz 1959; Martin and Barkley 1961; Davis 1993). We used frequency of occurrence to present our results (Corbett 1989). Food items found were counted only once as being present or absent. We visually estimated the percentage of scat volume for each food item. Plant material that occurred in trace amounts were excluded from the calculation of overall plant frequency of occurrence because ingestion was likely incidental to consumption of other foods. Occurrence of grass in Coyote scats was not included in the calculation of overall plant frequency of occurrence, because the nutritional value of grass in a Coyote diet is questionable (Fichter et al. 1955).