Food Habits of Four Species of Rodents on a Short-Grass Prairie in Colorado

Abstract

Food habits of four rodents (Dipodomys ordM, Onychomys leucogaster, Peromyscus maniculatus, and Spermophilus tridecemlineatus) of a shortgrass prairie ecosystem in northeastern Colorado were studied in 1969 and 1970 through microscopic analysis of stomach contents. Mean per cent volumes of animal matter in diets of these rodents over the entire study were: D. ordii, 4.4 per cent; O. leucogaster, 73.9 per cent; P. maniculatus, 39.0 per cent; and S. tridecemlineatus, 44.0 per cent. The greatest amount of seasonal variation in per cent volume animal matter in the diet was in P. maniculatus. Animal matter in diets of all four species was composed almost entirely of arthropods and a few parts of vertebrates. The most common arthropods included adult and larval Coleoptera, larval Lepidoptera, and grasshoppers (except in D. ordii). Plant matter in the diets of all species included leaves, stems, and flowering parts of various species of grasses, sedges, forbs, and shrubs, seeds (unidentified), and tissues of mosses, lichens, and fungi. Seeds were the most common type of plant matter in diets of D. ordii and P. maniculatus, whereas plant matter in S. tridecemlineatus and O. leucogaster was more equally divided between seeds and nonseed parts of grasses (and sedges) and forbs. Much seasonal variation in types and relative amounts of different kinds of plant and animal matter was noted.Information on food habits of rodents in short-grass and mixed-grass prairies, such as occur in eastern Colorado, is limited. Because food habits reveal much about the niche of a species, stomach analyses were undertaken on four dominant species of rodents in the short-grass prairies of northeastern Colorado. These species were Ord's kangaroo rat (Dipodomys ordii), northern grasshopper mouse (Onychomys leucogaster), prairie deer mouse (Peromyscus maniculatus), and thirteen-lined ground sqUirrel (Spermophilus tridecemlineatus) . Other rodents captured or seen but not included in this study include the silky pocket mouse (Perognathus flavus), hispid pocket mouse (Perognathus hispidus), muskrat (Ondatrazibethicus), western harvest mouse (Reithrodontomys megalotis ), northern pocket gopher (Thomomys talpoides), and black-tailed prairie dog (Cynomys ludovicianus).

Characterization of the Hanford 300 area burial grounds. Task IV. Biological transport

“…Free water i s not necessary for t h i s species providing there i s an ample supply of green vegetation and arthropods. These two food items make up a large part of the deer mouse d i e t , especially during the growing season (Flake, 1973;Johnson, 1975).…”

Feeding ecology and laboratory predatory behavior toward live and artificial moving prey in seven rodent species

“…We placed first the highly carnivorous O. leucogaster (the grasshopper mouse). Most of the vegetable matter ingested by these mice is probably a by-product of catching herbivorous insects (Flake, 1973). Because of a relative lack of data, P. californicus (the California mouse) was more difficult to rank and was placed alternatively second and fourth.…”

Differences in the decision to attack between grasshopper mice and hamsters: Effects of novel, noxious, and aversive stimuli

“…For example, the decision to attack may be more resistant to potential inhibitory situations in grasshopper mice (Onychomys leucogaster) than in hamsters (Mesocricetus auratus) , because grasshopper mice depend on their attack response for food more than do hamsters. Grasshopper mice feed almost exclusively on arthropods (Flake, 1973), whereas hamsters eat primarily plants, with some arthropods (Polsky, 1977). Novelty of the test situation, the added presence of noxious stimuli, or a developed aversion toward prey are all situations that could inhibit an attack response.…”