Diptera: Cuterebridae: Cuterebra cyanella mt.
Siphonaptera: Callistopsyllus deuterus m, Catallagia decipiens m, Epetedia stanfordi mt, Malaraeus sinomus mt, Malaraeus telchinum mt, Megarthroglossus procus mt, Monopsyllus wagneri wagneri mt, Orchopeas leucopus mt, Peromyscopsylla hesperomys adelpha mt, Phalacropsylla allos t, Rhadinopsylla sectilis goodi t, Stenistomera macrodactyla m, Stenoponia (ponera or americana) mt.
Cestoda: Choanotaenia sp. m, Hymenolepis sp. t.
Nematoda: Mastophorus numidica mt, Syphacia obvelata mt, Trichuris stansburyi t.
Acanthocephala: Moniliformis clarki mt.
In order to determine the relative numbers of each species of Peromyscus that were taken on a seasonal basis by predators, scats of coyotes and foxes were collected from trails and roads at least twice each month, from September 1963 through August 1964. Scats were identified, labeled and dried; all bones and samples of hair were later removed from each scat. Scats that were intermediate in size between the droppings of foxes and coyotes, and that could not be identified readily in the field, were not collected. Bones from the scats were identified to species, and hair was identified to genus or species by comparing color patterns or cuticular patterns with samples from known mammals. More than 200 impression slides and whole mounts of guard hair and underfur were prepared.
Seven individuals of P. truei and three individuals of P. maniculatus were represented in 114 coyote scats ([Table 13]). Both species of Peromyscus comprised only 3.9 per cent of the 253 items of food represented in the 114 scats. Rabbits, Sylvilagus sp. and mule deer, Odocoileus hemionus were the major food items of coyotes. Mice of the genus Peromyscus apparently were preyed upon mostly in autumn (September through November), when mouse populations were near their yearly peaks.
Foxes also prey upon Peromyscus in the park. One P. truei was represented in the 16 scats of foxes that were analyzed. This individual was taken in the winter quarter (December through February).
The bobcat may be an important predator upon Peromyscus in this region, but few scats of this animal were found. Since these could not be assigned to a specific month, they were not saved for analysis. Anderson (1961:58) believed that bobcats and gray foxes were the most abundant predators in the park. My observations over a period of two years led me to conclude that coyotes were more abundant than foxes and that foxes were, in turn, more abundant than bobcats.