Aerial baiting for wild dogs has no observable impact on spotted-tailed quolls (Dasyurus maculatus) in a rainshadow woodland

Abstract

The short-term impact of 1080 aerial baiting for wild dogs (Canis lupus dingo, Canis lupus familiaris and hybrids of the two) on spotted-tailed quolls (Dasyurus maculatus) was investigated at a rainshadow woodland site in southern New South Wales, Australia. Sixteen quolls were trapped and fitted with radio-transmitters containing mortality sensors. Three feral cats were also opportunistically trapped and radio-collared. One week after trapping ceased, meat baits nominally containing 6 mg of 1080 poison and 50 mg of the biomarker rhodamine B were deployed aerially over a 10-km transect across the study area. Following bait deployment, collared quolls and cats were monitored daily over four weeks for evidence of mortality. During this time, one quoll and two cats died. The quoll did not die from 1080 but both cats showed clear signs of poisoning. Whisker samples were obtained from trapped quolls 5–8 weeks after baiting to determine whether they had been exposed to baits. Of the 15 remaining collared quolls, 12 were retrapped. Four of these tested positive for rhodamine B. Three individuals originally collared were not retrapped but confirmed alive at least seven weeks after bait deployment. A further six non-collared quolls were also trapped, with two of these positive for rhodamine B. Of the 19 quolls from which whisker samples were tested for rhodamine B then, 13 (68%) were negative and six (32%) were positive. Aerial baiting had no observable impact on the local radio-collared quoll population, a finding consistent with results from a similar study recently conducted in northern New South Wales.