Are canid pest ejectors an effective control tool for wild dogs in an arid rangeland environment?

Abstract

Context: Wild dogs are a significant pest species of livestock production and native wildlife in Australia. A suite of control tools is used to mitigate predation impacts. Baiting with sodium fluoroacetate is the most commonly used control tool in Australia; however, its effectiveness can be reduced by interference by non-target species, and in some contexts by microbial degradation of the toxin. Canid pest ejectors (CPEs) are a mechanical device with an attractant ‘lure head’ designed to eject a lethal toxin into the mouth of canids pulling on the lure head. A range of lure heads can be used to attract canids to pull, and trigger CPEs.Aims: We aimed to determine whether uptake of CPEs by wild dogs in an arid rangeland environment could cause a decline in a wild dog population. We also aimed to determine whether there are particular lure heads that increase the rate of CPEs being triggered by wild dogs.Methods: We deployed one hundred CPEs over four sessions of control across three properties in the southern rangelands of Western Australia from 2018 to 2020. Each session consisted of 2 months of CPE deployment with two different lure heads, totalling eight lure head types over the entire study. All CPEs were monitored using camera traps.Key results: Wild dog density varied over the study period. In all four control sessions, a decrease in wild dog density was recorded (–46%, –5%, –13%, –38%). Wild dog activity events on camera and their interest in CPEs differed between sessions and lures (i.e. higher with scent-based lures). Non-target species did not interfere with CPEs significantly, despite a higher number of activity events by non-target species than wild dogs.Conclusions: CPEs caused a reduction of 5–46% of wild dog density when deployed in the southern rangelands of Western Australia. Non-target interference was minimal when using CPEs for wild dog control.Implications: Use of scent-based lures on felt lure heads is recommended for successful use of CPEs for wild dog control in arid rangeland environments. Future on-ground wild dog control should include CPEs as a complementary tool for the reduction of wild dog density.