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USGS · 70255940

Mammalian lures monitored with time-lapse cameras increase detection of pythons and other snakes

Abstract

Background Enhancing detection of cryptic snakes is critical for the development of conservation and management strategies; yet, finding methods that provide adequate detection remains challenging. Issues with detecting snakes can be particularly problematic for some species, like the invasive Burmese python ( Python bivittatus ) in the Florida Everglades. Methods Using multiple survey methods, we predicted that our ability to detect pythons, larger snakes and all other snakes would be enhanced with the use of live mammalian lures (domesticated rabbits; Oryctolagus cuniculus ). Specifically, we used visual surveys, python detection dogs, and time-lapse game cameras to determine if domesticated rabbits were an effective lure. Results Time-lapse game cameras detected almost 40 times more snakes ( n = 375, treatment = 245, control = 130) than visual surveys ( n = 10). We recorded 21 independent detections of pythons at treatment pens (with lures) and one detection at a control pen (without lures). In addition, we found larger snakes, and all other snakes were 165% and 74% more likely to be detected at treatment pens compared to control pens, respectively. Time-lapse cameras detected almost 40 times more snakes than visual surveys; we did not detect any pythons with python detection dogs. Conclusions Our study presents compelling evidence that the detection of snakes is improved by coupling live mammalian lures with time-lapse game cameras. Although the identification of smaller snake species was limited, this was due to pixel resolution, which could be improved by changing the camera focal length. For larger snakes with individually distinctive patterns, this method could potentially be used to identify unique individuals and thus allow researchers to estimate population dynamics.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 25.103410837459833° to 26.337274298622603° latitude; -81.34055052477085° to -80.06716804534993° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Marina E. McCampbell, McKayla M. Spencer, Kristen Hart, Gabrielle Link, Andrew J. Watson, Robert A. McCleery. 2024-06-24. Mammalian lures monitored with time-lapse cameras increase detection of pythons and other snakes. https://doi.org/10.7717/peerj.17577

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