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We compared two bait station techniques for determining the sex and identifying individual spotted-tailed quolls (Dasyurus maculatus gracilis) using images taken by camera traps. One method used bait in a plastic mesh bag and the other was a new method using a raised bait canister to entice the quolls to stand on their hind legs and present their ventral surface to the camera. Individuals were identified from multiple images of their unique spot pattern, and sex was determined from ventral images. The bait bag method was better for detecting quolls and both methods performed similarly in allowing observers to identify individuals from images. However, the bait canister method was superior for determining sex of individuals. Using this new bait canister method, individual identification was possible in 202 out of 206 detection events and the sex of 81% (47 of 58) of identified individuals was confidently assigned from multiple detections. This bait station design can therefore provide additional data on individual quolls and reduces the need for more invasive live-trapping techniques. This methodology could be adapted for other mammals in Australia and worldwide.

ContextFeral cats have been identified as a key threat to Australia’s biodiversity, particularly in arid areas and tropical woodlands. Their presence, abundance and potential impacts in rainforest have received less attention. AimsTo investigate the distribution and diet of feral cats (Felis catus) in upland rainforest of the Wet Tropics. MethodsWe collated available occurrence records from the Wet Tropics, and data from upland camera-trapping surveys over an 8-year period, to assess geographic and elevational distribution of feral cats in the bioregion. We also assessed the diet of feral cats from scats collected at upland sites. Key resultsFeral cats are widespread through the Wet Tropics bioregion, from the lowlands to the peaks of the highest mountains (>1600m), and in all vegetation types. Abundance appears to vary greatly across the region. Cats were readily detected during camera-trap surveys in some upland rainforest areas (particularly in the southern Atherton Tablelands and Bellenden Ker Range), but were never recorded in some areas (Thornton Peak, the upland rainforest of Windsor Tableland and Danbulla National Park) despite numerous repeated camera-trap surveys over the past 8 years at some of these sites. Scat analysis suggested that small mammals comprise ~70% of the diet of feral cats at an upland rainforest site. Multivariate analysis could not detect a difference in mammal community at sites where cats were detected or not. ConclusionsFeral cats are widespread in the Wet Tropics and appear to be common in some upland areas. However, their presence and abundance are variable across the region, and the drivers of this variability are not resolved. Small mammals appear to be the primary prey in the rainforest, although the impacts of cats on the endemic and threatened fauna of the Wet Tropics is unknown. ImplicationsGiven their documented impact in some ecosystems, research is required to examine the potential impact of cats on Wet Tropics fauna, particularly the many upland endemic vertebrates. Studies are needed on (1) habitat and prey selection, (2) population dynamics, and (3) landscape source–sink dynamics of feral cats in the Wet Tropics.

A cage for continuous intra-arterial or intravenous infusion is described. Major features are: a) The animal is free to move during infusion, b) loss of the infused solution is avoided, c) cleaning and decontamination are simple, and d) infusion can continue for weeks.