Lures change the detectability of feral cats on the arid landscape

Feral cats (Felis catus) are difficult to manage and harder to detect. For 20 years, we have been using an annual aerial baiting program to suppress feral cat numbers on the Matuwa National Park in Western Australia. The efficacy of this management is monitored via pre-bait and post-bait surveys of feral cat activity on sandy tracks, and at least 120 camera-traps. In 2021, we detected cats on only five occasions, despite using 130 camera-traps with an olfactory lure known as Catastrophic. In this study, we measured the detectability of feral cats at three camera-traps arrangements on Matuwa: passive cameras (n = 57), camera with the Catastrophic lure (n = 120), and cameras with a Magnum Scrape-Dripper (R) (n = 63) dispersing cat urine. All 120 sites had two cameras, one with Catastrophic for comparison with data from prior surveys, plus a camera that was either passive or had a dripper. Camera-traps were active for an average of 57 days (range 55-60 days). Cats were detected by cameras with drippers 29 times more than passive cameras and six times more than Catastrophic cameras. Further, cats spent on average 2.6 s in front of passive cameras, 8.5 s in front of Catastrophic cameras, and 65.5 s in front of drippers. The ability to detect feral cats affects the magnitude and accuracy of abundance or occupancy estimates for cats. Therefore, our research highlights a severe weakness in current feral cat survey methodologies and any management decisions derived from that data.

Automated summary

The study reveals a significant weakness in current feral cat survey methods and emphasizes the importance of cat detectability for accurate estimates of feral cat abundance or occupancy.