Camera traps and pitfalls: an evaluation of two methods for surveying reptiles in a semiarid ecosystem

Abstract

Context Passive infrared cameras have become a widely utilised method for surveying mammals, providing substantial benefits over conventional trapping methods. Cameras have only recently been tested for their ability to survey terrestrial reptiles, and have not yet been tested against other reptile survey methods for their comparative effectiveness. Aims To investigate the reliability of passive infrared cameras as a reptile survey method, compared with pitfall trapping. In addition, to test a refinement of a current protocol for using cameras to survey reptiles. Methods The study was carried out in the herpetologically diverse, semiarid Mallee region of Victoria, Australia. Paired camera and pitfall lines were set up at 10 sites within Murray Sunset National Park and results from the two methods were compared. A comparison of results from cameras with and without the use of a cork tile substrate was also made. Key results Cameras were just as effective as pitfall traps for detecting some common diurnal species – detecting additional species that pitfalls did not – but were significantly less effective overall. Cameras provided lower estimates of species richness and failed to detect nocturnal species. We also discovered that cork tiles, required in other environments for the cameras to be effective in detecting diurnal reptiles, were not needed here. Conclusions Cameras can be an effective, efficient non-invasive alternative to conventional trapping methods, such as pitfall trapping, for surveying some terrestrial diurnal reptile species. However, further investigation into using cameras for surveying nocturnal reptile species is still required. Implications If the methodological issues identified during this study can be overcome, passive infrared cameras have the potential to be a valuable tool for future herpetological research.