Estimating Bobcat Abundance Using Automatically Triggered Cameras

摘要

Ineffective survey methods of carnivores limit the ability of managers and researchers to make sound research conclusions and management recommendations. Because bobcats (Lynx rufus) are individually identifiable due to their unique coat patterns, it may be possible to obtain density estimates using capture–recapture models. We photo-trapped bobcats on the 3,156-ha Welder Wildlife Foundation Refuge in southern Texas from September 2000 through August 2001 to determine whether automatically triggered cameras could produce reliable estimates of bobcat density. Using the Schumacher-Eschmeyer estimator, we obtained an abundance estimate of 15 individuals (95% CI = 13.6–16.7) from 56 bobcat photographs. Our estimate was comparable to bobcat densities previously reported on our study area. This technique has the potential to provide wildlife managers and researchers with reliable data on bobcat abundance not previously available without the expense of physical capture and radiotelemetry. Our relatively high photographic success might be attributable to the dense chaparral-type vegetation and the large network of travel pathways available on our study area. These methods may not be as successful in open areas or where bobcat travel is not predictable. We encourage replication of this technique elsewhere in bobcat range where density, vegetation, and travel pathways differ.