| Summary: | This study describes aspects of the descriptive, functional and social ecology of dingoes Canis lupus dingo from the Southern Greater Blue Mountains World Heritage Area, Australia. Amendments to the wild dog control order of the Rural Lands Protection act 1998 recommended that resident dingoes in this protected area be conserved in situ to maintain ecological function and to preserve wild “pure” dingo populations. Field work was based on and around two 25 kilometre transects, each within a separate site of varied rugged and forested terrain, within the core of this reserve. The aim was to investigate similar biological and ecological descriptors to those used in past studies of dingoes in Australia for comparison with this population. Objectives included morphometric measurements and colouration, genetic purity, patterns of prey consumption and changes in abundance, activity and spatial organisation to assess the functional role of dingoes in this universally significant protected area. Dingoes were trapped using padded soft jaw leg-hold traps by professional dingo trappers. Captured animals were weighed, measured, had tissue/blood samples collected for genetic tests, collared or tagged to observe patterns of movement, and released at the location of capture. Dingoes were tested for rare microsatellites found in captive dingoes and domestic dogs to estimate “purity”, and multilocus genotype data were compared within the population to determine relatedness. Patterns of prey consumption were assessed using scat analysis from dingo and fox scats sampled along each transect. Monthly variations in general patterns of dingo activity were tested using indices calculated from counting spoor on sand plots spaced approximately every kilometre on both transects. Spatial organisation was investigated using data logging global positioning system telemetry collars and analysed using minimum convex polygons and kernel contours. Twelve collars were outfitted to dingoes for 13 months and scheduled to log six to eight locations per 24 hours. Five additional collars were outfitted to dingoes for the 2007 breeding season and scheduled to log one location every ten minutes for 50-52 days. From 47 live captures, average morphometric measurements included: weight 16 ± 2.8kg; head length 234.2 ± 12.6mm; ear height 97.2 ± 5.9mm (n = 34); shoulder height 575.6 ± 29.4mm; hind foot length 183.6 ± 9.2mm (n = 17); tail length 423.3 ± 69.3mm (n = 46); and total length 1326.1 ± 88.7mm. Black and tan was the most common coat colour (38.3%) followed by sable (31.9%), tan (23.4%) and patchy (6.4%). Canonical scores to estimate “purity” ranged between 0.46 and 4.34 (n = 10) suggesting that 80% of the population was “pure” according to previously published “purity” descriptors. Alternatively, comparative analyses of microsatellites from captive dingo populations with the 47 live captures and one deceased individual sampled during field work suggested 2.1% of the population were likely “pure” dingoes, 16.7% was less than 75% dingo, 43.8% was less than 65% dingo and 37.5% was less than 50% dingo (n = 48). However, conclusions on “purity” depend on having a “pure” standard against which to compare current samples. Tests to investigate genetic relatedness showed each dingo could be assigned to one of eight closely related groups. Comparison of capture locations with relatedness data showed related individuals were either trapped within topographically defined areas or during extraterritorial explorations. Genetic relatedness data also showed variation in colouration between packs. In total, 1489 dingo and 962 fox scats were analysed for diet. Most commonly detected prey remains identified in dingo faeces was swamp wallaby (Site 1: 43.2% Site 2: 35.1%), brushtail possum (Site 1: 13.8%; Site 2: 7.8%) and eastern grey kangaroo in Site 2 (Site 1: 1.5%; Site 2: 12.6%). Twenty five species accounted for the remainder of the diet and included mammals, birds, reptiles and insects. Of the 11768 spoor counted whilst monitoring sand plots, 759 dingo tracks were recorded in Site 1 and 1048 were in Site 2 across all seasons. Dingo activity peaked and receded every six months on both transects and related directly with the expected seasonal activity of dingoes. Many strong positive and negative correlations between diet and activity of dingoes and activity of medium-large sized mammalian prey items were observed. Results implied that these interactions were synchronised at a landscape scale and potentially showed the functional role of dingoes as a higher order predator in this study area. Similar data on foxes showed no clear interactions with dingoes or prey species, although fox diet and activity patterns overlapped with dingoes. Dingoes maintained a mean home range of 34.2km2 (± 8.2 se) for 90% kernel contours and 5.9km2 (± 1.4 se) for 50% kernel contours (n = 47347 locations from 12 dingoes). Movement patterns identified included territory maintenance behaviours, extraterritorial forays by males and potential dispersal behaviour by females. Annual patterns of activity peaked during breeding seasons which could be related with activity peaks observed using data from sand plots. Daily activity, however, varied per individual but tended to have crepuscular peaks. Data implied breeding and pup rearing behaviours may have affected patterns of movement and activity the most. From this study, dingoes are redefined as a primitive hypercarnivorous member of the family Caninae from Australia, distinguished by one annual breeding cycle and morphometric parameters that characterise the dingoes found within specific geographic locations. Future management practices should focus on targeting problem dingoes in areas near pastoral land opposed to adopting widespread dingo control campaigns across the Greater Blue Mountains World Heritage Area. The cultural transmission of behaviours from dingoes to dingoes is identified as an essential natural phenomenon to maintain ecosystem stability and minimise livestock losses in pastoral areas surrounding the study area. Similarly, environmentally sustainable agricultural practices need to be adopted for holistic adaptive management of the region surrounding the Greater Blue Mountains World Heritage Area. Properties which are affected by dingo predation should be audited for assessment of objects which may attract or deter dingoes to or from their estate. During the process of an audit, landowners and the greater public need to be educated about dingo ecology and adaptive landscape management practices. Environmentally sustainable economic and land management policies may then be created and implemented for holistic management of Australian landscapes.
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