Hispid Cotton Rat (Sigmodon hispidus) in Nebraska: Distribution, Reproduction, and Seasonal Activity

Abstract

By 1975, hispid cotton rats were known from 6 counties in Nebraska-1 in the extreme southeastern corner and 5 in south-central parts of the state (Farney 1975). The northernmost locality was from Kearney County in 1966 and the westernmost was from Harlan County in 1973 (Farney 1975). At many former sites, S. hispidus was captured in roadside ditches with dense or tall vegetation, including brome (Bromus), foxtail (Setaria lutescens), sunflower (Helianthus), prairie cordgrass (Spartina pectinata), and switchgrass (Panicum virgatum; Jones 1960, Farney 1975). Both abiotic and biotic environmental pressures have been suggested as factors that limited movements of S. hispidus farther northward (Sauer 1983, Benedict et al. 2000). During the last 30 years in Nebraska, at least 20 native species of mammals have expanded their distribution in the state (e.g., Benedict et al. 2000, Roehrs and Genoways 2004, Serbousek and Geluso 2009), but others have contracted their ranges (Benedict et al. 2000). Although S. hispidus was last documented moving northward in the 1970s, Benedict et al. (2000) did not report a change in its distribution. A lack of change suggests that the distribution of S. hispidus has been stable since the 1970s, the species may be locally extinct, or researchers have not trapped in appropriate habitats in southern parts of the state. The main purpose of our study was to determine the current status of the hispid cotton rat in Nebraska. Herein, we also comment on its distribution, reproductive biology, and seasonal activity in the state.

Observations on the Distribution and Status of Selected Nebraska Mammals

“…Farney (1975) conducted extensive trapping in south-central Nebraska and added four counties (Franklin, Harlan, Kearney, and Webster) with material from Kearney County being the furthest north. Wright et al (2010), after two years of field studies in south-central and southwestern Nebraska, added seven counties (Chase, Dundy, Furnas, Hayes, Hitchcock, Nuckolls, and Red Willow) and 13 new localities to the geographic range of the species in Nebraska. The northern-most point in the movement of the hispid cotton rat stood at a place in northeastern Hayes County, and the Nuckolls County record reduced the gap between the central Nebraska records and the Richardson County site to four counties along the Kansas border (Wright et al 2010).…”

Range Expansion ofSigmodon hispidus(Hispid Cotton Rat) into Reclaimed Coal Surface-Mines in Southeastern Kentucky

“…Sigmodon hispidus Say and Ord (Hispid Cotton Rat) has the widest distribution of the genus throughout North America, ranging from Florida north to Virginia, west to Arizona, and from southern Nebraska to Texas and Mexico at the Lower Rio Grande Valley (Bradley et al 2008). Field surveys demonstrate that this species has expanded its range northward in New Mexico (Geluso et al 2005, Mohlhenrich 1961, northward and westward in Nebraska (Frisch et al 2015, Wright et al 2010, and northward in Missouri (Thompson and Finck 2013).…”