A Comparison of Snap Traps for Evaluating Small Mammal Populations
The authors compared rat, mouse, and museum special snap traps to determine if differences existed in capture efficiency of small mammals and whether type of trap affected indices of richness, evenness, and diversity. Small mammals were trapped in 57 streamside study areas in 1990 to 1995 in the Ouachita Mountains, AR. Efficiency of mouse traps was equal to or greater than that of museum special traps in capturing a small mammal species. Rat traps were most efficient for capturing the 2 largest small mammal species recorded, the eastern wood rat (Neotoma floridana) and the cotton rat (Sigmodon hispidus). The authors found no difference among the types of traps in their susceptibility to being inadvertently sprung by extrinsic factors such as rain. Mean species richness, evenness, and diversity did not differ among trap types. A combination of mouse and rat traps increased species richness and diversity over mouse traps alone. A combination of mouse, rat, and museum special traps did not greatly increase any community measure relative to the mouse and rat trap combination. The scientists conclude that use of museum special traps for sampling small mammals is unnecessary unless the objective is to acquire museum specimens.