The vast clearance of forest and woodland for agriculture with the removal of more than 93% of the native vegetation has decimated the fauna of what is now known as the Western Australian wheatbelt. This clearing has been particularly severe on wandoo woodlands through the wheatbelt. In order to quantify the usefulness of what has been left, three native woodland types were surveyed for avian abundance and diversity, in a large heterogeneous remnant of old-growth woodland, at Dryandra. Birds were counted at 70 points along seven transects, through three woodland types: powderbark wandoo (Eucalyptus accedens), wandoo (E. wandoo) and a brown mallet (E. astringens) plantation. Greater abundance and species richness were detected in E. wandoo woodland, although this is thought to be related to the more mesic and productive low-lying contours of the landscape on which it is situated.

Colour polymorphisms are common in nature, but their evolutionary significance and the mechanisms maintaining them sometimes remain poorly understood. Polymorphic green pythons (Morelia azurea and Morelia viridis) are born either red or yellow. Several processes are proposed to maintain such polymorphisms, and the assumption that colour is adaptive predicts that it may be correlated with a series of life-history and/or ecological traits. We examined 1090 green pythons from northern Australia and New Guinea and reveal strong geographic variation in the frequency of juvenile polymorphism. Some variation is explained by known genetic structure among populations, while stochastic processes (e.g. bottlenecks, founder effects) likely explain remaining variation. The yellow juvenile morph occurs in all populations of M. azurea and M. viridis, whereas the red morph occurs only in some populations of M. azurea and at varying frequencies. Yellow and red juveniles did not differ in morph-specific survival, sex ratios, morphology (tail length, head shape and mass) or diet. We discuss our results in relation to several hypotheses relating to maintenance of colour polymorphisms in nature. Although inconclusive, we are reluctant to suggest that colour is non-adaptive, and encourage additional experimental field research on the significance of polymorphism in these taxa.

Ecologists endeavour to develop survey techniques that are cost-effective for the species they target and robust enough for statistical analysis. Using time as a measure of effort, we compared visual encounter surveys with artificial cover objects (strapped to trees), targeting an arboreal elapid, the pale-headed snake (Hoplocephalus bitorquatus) and its potential prey (geckos). Within a red gum forest vegetation community with relatively high snake density, capture rates were 0.6 ± 0.1 (s.e.) snakes/person-hour using visual encounter surveys, compared with only 0.1 ± 0.1 snakes/person-hour using cover objects. The probability of detection of pale-headed snakes was estimated from occupancy modelling at 0.70 ± 0.06 in visual encounter surveys and 0.19 ± 0.09 in cover object surveys. Gecko capture rates (among all vegetation communities) were significantly greater (P < 0.001) using cover objects. The probability of detection of geckos was estimated from occupancy modelling at 0.77 ± 0.05 in visual encounter surveys and 0.97 ± 0.02 in cover object surveys. Geckos favoured (P < 0.001) cover objects facing south during all seasons except winter. Artificial cover objects may provide some value in detecting pale-headed snakes in vegetation communities where habitat resources are limited; however, where resources are plentiful, visual encounter surveys are likely to remain the most cost-effective survey option.

Chemical cues can alert prey to the presence of predators before the predator is within visual proximity. Recognition of a predator’s scent is therefore an important component of predator awareness. We presented predator and control scents to wild, wild-born captive, and predator-naive captive-born pygmy bluetongue lizards to determine (1) whether lizards respond to reptile chemical cues differently from controls, (2) whether captive lizards respond more strongly to a known predator than to other predatory reptiles, (3) whether captive-born lizards recognise predators innately, whether captive-born lizards have reduced predator recognition compared with wild lizards and whether time spent in captivity reduces responses to predators, and (4) whether the avoidance response to predator detection differs between naive and experienced lizards. There was no significant difference in the number of tongue flicks to predator scent among wild, wild-born and captive-born lizards, suggesting that predator detection is innate in the pygmy bluetongue lizard and time in captivity did not reduce predator recognition. The number of tongue flicks directed towards brown snake scent was significantly higher than that to the novel and water controls for all lizard origins. Lizards of all origins continued to bask in the presence of predator scents, suggesting that chemical cues alone may be insufficient to instigate an avoidance response and other cues may be required.

Intraspecific variation as a way to explore factors affecting the evolution of species traits in natural environments is well documented, and also important in the context of preserving biodiversity. In this study, we investigated the extent of behavioural, morphological and ecological variation in the peninsula dragon (Ctenophorus fionni), an endemic Australian agamid that displays extensive variation in colour across three allopatric populations. The aims of the study were to quantify variation across the different populations in terms of the environment, morphometric characteristics and behaviour. We found population level differences in habitat structure and encounter rates. Adult body size of C. fionni, as well as a range of morphometric traits, differed between populations, as well as the frequency of social interactions, which appears to be related to population density and abundance. Analysis of communicative signals showed differences between the southern and central populations, which appear consistent with variations in response to environmental differences between study sites. The findings of the present study, coupled with previous work examining colour variation in this species, show that the three populations of C. fionni have likely undergone substantial differentiation, and would make an interesting study system to explore trait variation in more detail.

It is increasingly recognised that intertaxon hybridisation is more common in vertebrates than previously thought. However, recent hybridisation has rarely been reported from wild marsupials, with only three instances of first generation (F1) hybrids reported, all in macropodids. In the 1990s a chromosomally anomalous population of black-footed rock-wallaby (Petrogale lateralis) was identified in the Townsend Ridges in central eastern Western Australia. Individuals from this population had chromosomes characteristic of two P. lateralis subspecies (P. l. centralis and P. l. kimberleyensis). This unusual mixture is suggestive of a novel hybrid zone between subspecies, but it could also represent a P. l. centralis population in which a 9–10 chromosome fusion has independently arisen. To test between these hypotheses, we compared mitochondrial DNA Control Region (CR) sequence data from Townsend Ridges individuals to published data for all P. lateralis subspecies. Two divergent lineages of CR haplotypes were identified at Townsend Ridges, suggesting that it represents a novel rock-wallaby hybrid zone, the third reported in the genus. While one CR haplotype clustered with those typical of P. l. centralis, the other Townsend Ridges haplotypes clustered with those from three different P. lateralis subspecies but not with P. l. kimberleyensis. Additional studies with multiple nuclear genes will be necessary to fully understand the nature of this novel hybrid zone.