Site fidelity and population structure of a solitary subterranean rodent, Geomys breviceps, in southwestern Arkansas

From October 2007 to April 2010, 87 Geomys breviceps were captured a total of 156 times on a 2-ha plot in southwestern Arkansas. Individuals were captured using the Sikes-Finley pocket gopher trap and all new captures were marked with passive integrated transponder (PIT) tags. Spatial distribution and movement patterns were examined using ArcGIS. The population was female biased. Average duration between initial capture and final recapture of individuals was 8 months. An individual male and female captured at the onset of the study were recaptured after 29 months and remained within 4 m of their initial capture site. Males were spaced closer to females and further from other males in a manner that potentially allowed them access to the maximum number of females. Larger males were more frequently captured within 20 m of significantly more females than smaller males. Individuals were recaptured up to five times and the average distance between captures of a single individual was 18 m with a maximum distance of 46 m. Movement patterns were similar for males and females. These data suggest high site fidelity for G. breviceps, with individuals residing in the same general area throughout their lifetime. This project provides the groundwork for future studies involving dispersal, population dynamics, and social behavior in this population.