Date of Award
Master of Science (MS)
Dr. Eugene Flaherty
A Sigmodon hispidus population in a relict grassland was studied by live-trapping from April, 1965, to February, 1969. The populations oscillated from high densities in the fall to low densities in the spring. Initial population declines were caused primarily by a normal cessation in the breeding cycle and accelerated by harsh winter weather, although other factors were probably involved. The population underwent a 92% turnover in six months. Ecological densities ranged from 0.0 to 20.6 animals/ acre/ month in the favored habitat. Exclusive boundary strip male seasonal home ranges (0.962 +/- 0.206 acres) averaged significantly larger (p = 0.01) than those of the females (0.543 +/- 0.090 acres) and males tended to be more nomadic than females. Animals tended to traverse smaller areas during periods of high densities. No indications of territorial defense were evident. Sigmodon hispidus preferred habitats with a dense undergrowth and a protective overstory although they utilized less-favored habitats during high density periods. The population consumed about 0.7% of the available vegetation produced on the area per year.
Copyright 1969 Michael Allen Mares
Mares, Michael Allen, "Ecological Aspects of Sigmodon Hispidus in a Mature Eco-System" (1969). Master's Theses. 1222.