The occurrence and relative abundance of small terrestrial mammals on Theda Station in the Northern Kimberley, Western Australia

Abstract

Significant gaps in knowledge currently exist regarding the small mammal fauna of the Northern Kimberley (NOK) bioregion. Theda Station is a previously unsurveyed pastoral lease in the NOK. The aim of the current study was to determine the presence of small mammals (non-volant, <2 kg) on Theda Station and to compare these findings with those recently obtained on the adjacent Doongan Station. Between 2006 and 2014, 226 site surveys were conducted across 69 sites, with over 26 000 trap-nights encompassing a range of habitats. Thirteen of the 27 small mammal species known to occur in the NOK were detected. Four species (Pseudomys nanus, Rattus tunneyi, Zyzomys argurus and Sminthopsis virginiae) were common, five (Pseudomys delicatulus, Pseudantechinus ningbing, Dasyurus hallucatus, Isoodon macrourus and Petropseudes dahli) were detected less frequently, and four (Leggadina lakedownensis, Hydromys chrysogaster, Planigale maculata and Petaurus breviceps) were occasionally recorded. Our study provides important baseline data for small mammals in this region. It highlights the lack of detailed knowledge of both the presence of, and temporal fluctuations in, the region’s small mammal fauna. This study supports a non-uniform distribution of the small mammal fauna across the NOK, with Theda Station lying within a transition zone between the high rainfall rugged coastal and near-coastal areas and the lower rainfall areas of the east.

Surveys of small and medium sized mammals in northern Queensland with emphasis on improving survey methods for detecting low density populations

“…Relative abundance was calculated for each species of mammal captured in Northern Gulf region. The relative abundance, species richness and capture rates of small and medium sized mammals identified in the Northern Gulf region is considerably lower than those reported in other studies across the top end of other parts of Northern Australia (Woinarski et al 2010;Legge et al 2011;Olds et al 2016;Olds et al 2017). An exception to this is the common brushtail possum (Woinarski et al 2010) which was the most common species recorded in the Northern Gulf region, although considered to be potentially declining in northern Queensland (Winter 2007).…”

“…Elliott and pitfall trap success during the plot surveys was also considerably lower than recorded on two properties in the Northern Kimberley, where trapping was undertaken between 2006-2014 (Olds et al 2016;Olds et al 2017), which occurred during a similar time frame to this study . For example, Olds et al (2016 recorded 2.7 captures per 100 trap nights for Elliott traps and 1.6 captures per 100 trap nights for pitfall traps whereas our study recorded 0.35 and 0.57 captures per 100 trap nights for Elliott and pitfall traps respectively.…”