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Hunting has an ambivalent relationship with conservation: it can deplete and threaten vulnerable wildlife but can also motivate protection and good stewardship. Here we advance the understanding of this relationship by examining the different forms of hunting in one community with a particular focus on the motivations and implications surrounding the use of dogs. We present a case study from Indonesian New Guinea. We use self-reported information concerning the hunting activities and success of thirty-three hunters who frequent the lowland costal forest of Tambrauw in West Papua Province. The hunters identified 301 successful kills in a total of 654 hours of hunting over a 7-month period. Five different prey species were reported. In declining order of kills there were the Timor deer (Cervus timorensis), Wild pig (Sus scrofa), Common spotted cuscus (Spilocuscus maculatus), Dusky pademelon (Thylogale brunii) and Grizzled tree kangaroo (Dendrolagus inustus). While hunting with guns was the least frequently used method it was the most effective while passive methods (traps and snares) was the least efficient in terms of time (49 hours with 50 kills), but also the most commonly employed (352 hours with 123 kills) Interestingly, active hunting without dogs or guns yielded more kills per hour than hunting with them (0.70 versus 0.38 kills per hour), especially for deer, but hunting with dogs is the only method that seems to favour pigs over deer. Hunting in the daytime was more effective for pigs and less effective for all other species regardless of method. Dogs are also valued for guarding hunters and their families (from animals, enemies and spirits). We find that dogs sometimes provoke conflicts and cause other problems. Hunting method impacts the quantity and composition of the hunt, but as we see for dog ownership and use also relates to other practices. More attention should be given to local hunting and the methods used.

Tropical ectotherms are regarded as being especially threatened by global warming, but the extent to which populations vary in key thermal physiological traits is little known. In general, central and peripheral populations are most likely to differ where divergent selection pressures are un-opposed by gene flow. This leads to the prediction that persistent and long-isolated lineages in peripheral regions, as revealed by phylogeography, may differ physiologically from larger centrally located lineages. We test this prediction through comparative assays of critical thermal limits (minimum and maximum critical thermal limits, CTmin, CTmax) and optimal performance parameters (B80 and Topt) across central and peripheral lineages of three species of ground-dwelling skinks endemic to the rainforests of northeast Australia. Peripheral lineages show significantly increased optimal performance temperatures (Topt) relative to central populations as well as elevated CTmin, with the latter trait also inversely related to elevation. CTmax did not vary between central and peripheral lineages, but was higher in a forest edge species than in the forest interior species. The results suggest that long-isolated populations in peripheral rainforests harbour genotypes that confer resilience to future warming, emphasizing the need to protect these as well as larger central habitats.

We identify the 10 major terrestrial and marine ecosystems in Australia most vulnerable to tipping points, in which modest environmental changes can cause disproportionately large changes in ecosystem properties. To accomplish this we independently surveyed the coauthors of this paper to produce a list of candidate ecosystems, and then refined this list during a 2-day workshop. The list includes (1) elevationally restricted mountain ecosystems, (2) tropical savannas, (3) coastal floodplains and wetlands, (4) coral reefs, (5) drier rainforests, (6) wetlands and floodplains in the Murray-Darling Basin, (7) the Mediterranean ecosystems of southwestern Australia, (8) offshore islands, (9) temperate eucalypt forests, and (10) salt marshes and mangroves. Some of these ecosystems are vulnerable to widespread phase-changes that could fundamentally alter ecosystem properties such as habitat structure, species composition, fire regimes, or carbon storage. Others appear susceptible to major changes across only part of their geographic range, whereas yet others are susceptible to a large-scale decline of key biotic components, such as small mammals or stream-dwelling amphibians. For each ecosystem we consider the intrinsic features and external drivers that render it susceptible to tipping points, and identify subtypes of the ecosystem that we deem to be especially vulnerable.

We identify the 10 major terrestrial and marine ecosystems in Australia most vulnerable to tipping points, in which modest environmental changes can cause disproportionately large changes in ecosystem properties. To accomplish this we independently surveyed the coauthors of this paper to produce a list of candidate ecosystems, and then refined this list during a 2-day workshop. The list includes (1) elevationally restricted mountain ecosystems, (2) tropical savannas, (3) coastal floodplains and wetlands, (4) coral reefs, (5) drier rainforests, (6) wetlands and floodplains in the Murray-Darling Basin, (7) the Mediterranean ecosystems of southwestern Australia, (8) offshore islands, (9) temperate eucalypt forests, and (10) salt marshes and mangroves. Some of these ecosystems are vulnerable to widespread phase-changes that could fundamentally alter ecosystem properties such as habitat structure, species composition, fire regimes, or carbon storage. Others appear susceptible to major changes across only part of their geographic range, whereas yet others are susceptible to a large-scale decline of key biotic components, such as small mammals or stream-dwelling amphibians. For each ecosystem we consider the intrinsic features and external drivers that render it susceptible to tipping points, and identify subtypes of the ecosystem that we deem to be especially vulnerable. © 2011 Elsevier Ltd.

In this study, we examined whether a group of plant secondary metabolites - the formylated phloroglucinol compounds (FPCs), which are known to deter feeding on eucalypt foliage by captive marsupial folivores - influence feeding by wild common brushtail possums. There was at least a six-fold range of FPC concentrations in the foliage of individual trees within a single eucalypt species. Possums largely avoided trees with high FPC concentrations. While some trees with low FPCs were used heavily, others were not; thus the relationship between FPC concentration and tree use was polygonal rather than linear. We used a randomization procedure to demonstrate a relationship between the upper limits of FPC concentration and tree use. In contrast, this procedure showed that neither the nitrogen content nor the in vitro digestibility of the leaves influenced the use of trees by possums. Our results show that plant secondary metabolites, with a demonstrable mode of action, affect the selection of individual eucalypt trees by wild folivores. Thus, FPC concentrations may influence the distribution and abundance of marsupial folivores at landscape scales.