Trapping study of the endangered Key Largo cotton mouse (Peromyscus gossypinus allapaticola)

Abstract

The Key Largo cotton mouse (Peromyscus gossypinus allapaticola), a federally endangered sub-species of the cotton mouse, is currently restricted to less than 50% of its former habitat. Over the past 25 years, research has documented population declines, but little research has addressed either the population trends or the rate of this decline. Current sampling methods are labor intensive and budgetary and personnel constraints have led to sparse monitoring of the Key Largo cotton mouse populations. The objective of this project was to use a modeling approach to evaluate changes in the population estimate by trapping combinations of grid subsets from 34 nested-grids to create parameter estimates during one or several trapping sessions. Trapping grids were used to estimate density and total population from Key Largo cotton mouse capture data. This sampling methodology reduces the labor intensity and overall cost of current monitoring methods, and allows managing agencies to monitor population trends in an effort to maintain or increase populations of the endangered Key Largo cotton mouse.