Australian Journal of Zoology
Volume 68
Number 2 2020
During the vast clearance of forests and woodlands for agriculture, those on the best soils were taken first, resulting in a loss of some woodland types and the homogenisation of the woodlands. This study used a point-transect method at a surviving heterogeneous woodland to test what woodland type supported the greatest abundance and biodiversity of birds. Eucalyptus wandoo woodland had the greatest carrying capacity, a result related to its moist and more productive soils.
Photo by John Lawson.
Juvenile green pythons are strikingly polymorphic, but the mechanism maintaining this polymorphism in nature is unknown. We examined geographic variation in morph frequencies and differences in morphology, sex ratios, and survival between the two colour morphs. Morph frequencies vary across the geographic range of green pythons, but colour does not correlate with any ecological traits.
Photo by Daniel Natusch.
Using time as a measure of effort, we compared visual encounter surveys with artificial cover objects, targeting the pale-headed snake and its potential prey (geckos). Within a vegetation community with relatively high snake density, capture rates were six times greater using visual encounter surveys. Artificial cover objects may provide some value in detecting pale-headed snakes where habitat resources are limited; however, where resources are plentiful, visual encounter surveys are likely to remain the most cost-effective survey option.
Photo by Michael B. Shelton.
Many captive-born animals have lower survival compared with wild animals when released into the wild during translocations. We investigated the effect of captivity on predator recognition and found that pygmy bluetongue lizards can innately recognise reptile predator scent and time in captivity did not reduce recognition. As lizards did not show avoidance towards predator scent, it suggests that lizards require additional predator cues to cause a predator-avoidance response.
Photo by Tara Daniell.
A single species can show variation in appearance and behaviour across different populations and serves to demonstrate the importance of habitat and/or environmental conditions. The peninsula dragon is an Australian agamid lizard that exhibits geographical variation in colouration, body size and territorial display behaviour. In this preliminary study, we explore how this variation relates to aspects of the environment and relative abundance.
Photo by Jose Antonio Ramos.
Although of evolutionary interest, recent hybridisation has rarely been reported from wild marsupials. An anomalous population of black-footed rock-wallabies (Petrogale lateralis) from central eastern Western Australia has been found to have chromosomes characteristic of two P. lateralis subspecies, as well as two highly divergent lineages of mitochondrial DNA. These findings suggest that this population represents a novel rock-wallaby hybrid zone, the third now discovered in the genus.
Photo by David Pearson.
and John Lawson
