Boundary-strip Width for Density Estimation Based on Telemetric Locations

The mean maximum distance moved (MMDM) of a southern fox squirrel (Sciurus niger niger) population during a l2-day trapping period was compared between radiotelemetry and capture location data. MMDMs derived from capture locations averaged 51% less than MMDMs derived from telemetric locations. In addition, tests of MMDMs based on capture locations failed to detect a difference between sexes, whereas MMDMs based on telemetric locations indicated a significant difference. Density estimates of the fox squirrel population were calculated using MMDM/2 as an estimate of boundary-strip width (W) to compensate for "edge effect." A combined density estimate based on capture locations was 27% larger than the estimate based on telemetric locations. Because MMDMs derived from capture locations depend on the number of recaptures and are a function of trap spacing, W is often underestimated, resulting in positively biased density estimates. Density estimates located onˆW derived from telemetric locations may be less biased than estimates based on capture locations. Thus, radiotelemetry may help provide more reliable density estimates, particularly when recaptures are few.

Starting page
Ending page