The loss and degradation of habitat poses the single greatest threat to imperiled species in the United States (Wilcove et al. 1998). Limited availability of conservation resources requires conservationists to prioritize areas for protection, and as a result they face the urgent task of determining the geographic distributions of imperiled taxa (Groom et al. 2006). For many rare small mammals, however, such distributional data are incomplete and additional inventories are warranted if their critical habitats are to be identified and preserved.

The literature thoroughly documents trap type as an important variable in the capture of small mammals (e.g., Sealander and James 1958; Wiener and Smith 1972; Kalko and Handley 1993; Kirkland and Sheppard 1994; Francl et al. 2002; Umetsu et al. 2006). A number of factors may predispose a species to be captured more often in one trap type than another, including body size and behavior. For example, some shrews may be too small to engage the trigger mechanism of a typical live trap, whereas saltatory species (those adapted for jumping or hopping) such as jumping mice may be reluctant to enter the confined space of a live trap. Consequently, multiple sampling techniques and protocols are often necessary for a comprehensive mammal inventory (Jones et al. 1996).

Multiple sampling techniques and protocols are often necessary for a comprehensive mammal inventory.