Oral presentation- Open Session 12th International Mammalogical Congress

Optimising the detection and enumeration of northern quoll (Dasyurus hallucatus) populations using trail cameras (#379)

Scott Burnett 1 , Matthew Hemmings 1 , Nicholas Foster 1
  1. University of the Sunshine Coast, Sippy Downs, Queensland, Australia

Trail cameras have rightly replaced cage traps as the instrument of choice in many ecological studies. The quolls (Dasyurus spp.) are excellent candidates for trail camera detection studies given their opportunistic dietary behaviour and their uniquely marked coats;, however there has been limited benchmarking of trail camera performance against live-trapping approaches, nor research into deployment methods to optimise quoll detection. We therefore compared the relative ability of trail cameras compared to cage traps, and of various trail camera orientations, spacings and duration to; (i) detect northern quolls at a site, (ii) detect the largest number of northern quolls at a site and, (iii) collect data suitable for Mark-Recapture and SECR analyses. We show that on our 1 km long transects in north-east Queensland, trail cameras perform at least as well as cage traps in all parameters measured. We further demonstrate that camera orientation on the horizontal plane does not influence the probability of detecting a quoll and that new quoll individuals continue to accumulate steadily up to 12-14 days. Camera trap spacing has a strong influence on the number of quolls detected over a 1 km transect, with 100 m -apart spacings resulting in twice as many individuals detected as 250 m spacings. Even in these high-density quoll populations, linear transects don’t generate sufficient recaptures to facilitate mark-recapture or SECR modelling and a grid-based approach is recommended for studies where population size estimation is an objective.