Context. Ground-based shooting is widely used in management programs aiming to alleviate the impacts of invasive or overabundant wildlife populations. However, evaluations of individual shooting operations have shown variable results, and the effectiveness of ground-shooting as a population-management intervention has not been systematically examined.

Aims. Our review aimed to (1) assess the efficacy of shooting as a population management tool, and (2) identify commonalities among studies that will help managers identify situations where ground-shooting is most likely to be effective.

Methods. We systematically reviewed the literature to identify studies involving ground-shooting. From each study, we collated information about operational objectives, target taxa, geographic context, type of shooter used, effort, effectiveness, and use of additional control tools.

Key results. Most studies had no a priori quantifiable objectives. However, 60% of the 64 case studies produced a detectable reduction in population density and/or damage. The most common type of operation used unpaid or commercial harvest-oriented shooters to reduce herbivore density or damage. Only 30% of the operations that used volunteer shooters or recreational hunters achieved their objectives. Target taxa, geographic area or integration of shooting with other population-control methods had no detectable effect on the effectiveness of shooting operations. Common factors that hindered the effectiveness of shooting operations included immigration of target species from adjacent areas (n = 13), decreasing effort from shooters as the target population declined (n = 7) and selective harvesting (n = 7).

Conclusions. Ground-based shooting can be an effective management tool for overabundant wildlife populations, but many shooting operations did not achieve a notable decrease in animal abundance or damage. The source of failure could often be attributed to an inability to remove a sufficient proportion of the population to cause a population decline.

Implications. Managers contemplating using ground-based shooting to reduce the impacts or density of wildlife populations should (1) carefully consider whether this is a suitable management tool to achieve the desired outcomes, (2) establish clear objectives that aim to meet defined outcomes and allow for continuous improvement, and (3) ensure that operations are sufficiently resourced to achieve and maintain those objectives.

Context. Managing small, isolated populations requires conservation practitioners to weigh up the risks of inbreeding depression and outbreeding depression when assessing alternative management actions aimed at preventing species extinction. Accordingly, it is important that research intended to guide these management decisions provides the relevant evidence to inform them.

Aims. To determine the extent to which studies that use genetic analyses to characterise population units for conservation consider the key theoretical concepts necessary for making sound management recommendations regarding the desirability of gene flow among units, notably the consequences and relative risks of inbreeding depression and outbreeding depression.

Methods. A systematic search was conducted of peer-reviewed literature for studies that attempted to identify population units of threatened birds and mammals. Using content analysis, the theoretical framing of these studies was assessed, based on the discussion of key concepts concerning differences among populations.

Key results. There has been a significant increase over time in the number of published studies that use genetics to identify population units for conservation. Many do not consider theoretical concepts relevant to the effective management of fragmented populations of threatened species. Mammals were more common than birds as focal species of studies, but the number of concepts used in the framing of the studies was similar for these two taxa, despite differences in their ecology and biology that might be expected to affect perceptions of distinctiveness. Nevertheless, species of greater conservation concern tended to have a slightly more comprehensive theoretical framing.

Conclusions. There is great potential for more studies to implement theoretical guidelines and practical decision support tools when considering the best course of action for identifying appropriate population units for conservation management.

Implications. The gap in the identified literature is likely to be impacting the ability of conservation practitioners to make evidence-informed decisions about how to manage the genetic health of threatened species; it would be valuable to improve this situation.

Context. To re-establish a population of the threatened numbat (Myrmecobius fasciatus) in a newly created safe haven at Mount Gibson Wildlife Sanctuary, in the semi-arid zone of Western Australia, wild-born and captive-bred individuals of both sexes were translocated.

Aim. To compare: (1) the use of refuges by wild-born numbats pre- and post-translocation, and (2) the survival and refuge use of captive-bred numbats compared with wild-sourced numbats post-translocation.

Methods. Monitoring via radio-tracking facilitated the gathering of information on survival and behaviour of numbats pre- and post-translocation, and allowed a comparison of how different factors (e.g. captive-bred or wild-born; male or female) influenced survival and establishment in a new environment.

Key results. There were no significant differences in survival between sexes or between wild-born and captive-bred individuals. However, there were some differences in behaviour between sexes and source populations. Captive-bred numbats, regardless of sex, made greater use of tree hollows as nocturnal refuges than did their wild-born counterparts. Among wild-born numbats, there was a comparatively greater use of tree hollows and logs on the ground by males at Mount Gibson than at Scotia. The use of diurnal escape refuges did not vary between sexes or between captive-bred and wild-born individuals.

Conclusions. On the basis of the information presented here, we conclude that, in the absence of predation by mammalian predators, and with suitable release habitat, captive-bred-to-wild translocations of numbats may be as likely to succeed as are wild-to-wild translocations, at least over the first few months post-translocation.

Implications. Optimising the size and genetic diversity of the founding population by using animals from a variety of sources may not need to be heavily constrained by concerns about the ability of captive-bred numbats to adapt to and survive life in the wild.

Context. Australia has experienced the highest number of mammal extinctions of any continent over the past two centuries. Understanding the demography and spatial requirements of populations before declines occur is fundamental to confirm species trajectory, elucidate causes of decline and develop effective management strategies.

Aims. We evaluated the demography and spatial requirements of a northern quoll, Dasyurus hallucatus, population on Groote Eylandt, Northern Territory. Groote Eylandt is considered a refuge for the species because key threatening processes are absent or limited; cane toads and introduced ungulates are absent, feral cats are infrequently detected and the fire regime is benign compared with mainland Northern Territory.

Methods. We conducted a 4-year capture–mark–recapture study to monitor growth, reproduction and survival of northern quolls within a 128-ha area, and we evaluated spatial requirements by attaching GPS units to both sexes. To assess the status of the Groote Eylandt population, we compared the demographics with existing data from mainland populations.

Key results. The average density of northern quolls was 0.33 ha⁻¹. However, there was a 58% decline in female density, primarily between 2012 and 2013, corresponding with a decrease in female body mass. Females survived and bred in up to 3 years and adult survival rates did not vary among years, suggesting that juvenile recruitment drives population fluctuations. Male quolls were semelparous, with die-off occurring in the months following breeding. The median female and male home ranges were 15.7 ha and 128.6 ha respectively, and male ranges increased significantly during breeding, with 1616 ha being the largest recorded.

Conclusions. The northern quoll population on Groote Eylandt had a higher density, female survival and reproductive success than has been previously recorded on the mainland. However, a marked decline was recorded corresponding with a decrease in female mass, indicating below-average rainfall as the likely cause.

Implications. Groote Eylandt remains a refuge for the endangered northern quoll. However, even in the absence of key threatening processes, the population has declined markedly, highlighting the impact of environmental fluctuations. Maintaining the ecological integrity of Groote Eylandt is imperative for population recovery, and managing threats on the mainland over appropriate spatial scales is necessary to increase population resilience.

Context. Soft-release involving supplementary feeding or shelter is commonly used in wildlife reintroduction and rehabilitation projects. However, competition for nestboxes and supplementary feed, as well as predation at feed stations or nestboxes, can reduce the benefits of soft-release. The use of microchip-automated technology can potentially alleviate these concerns, by providing targeted supplementation to only the intended, microchipped animals.

Aims. We aimed to train wild-caught northern brown bandicoots, Isoodon macrourus, to use microchip-automated doors to access safe refuge.

Methods. Bandicoots were trapped from the wild and brought to the Hidden Vale Wildlife Centre, where eight were trained to use the doors in a six-stage process, and then six were trained in a three-stage process, using a peanut butter reward.

Key results. Bandicoots learned to use the doors in as few as 3 days. The duration of visits to the door generally increased during training, although the number of visits decreased.

Conclusions. The bandicoots successfully learned to use the microchip-automated doors, which shows that this technology has great potential with wildlife, particularly given the short training times required.

Implications. The use of these microchip-automated doors with wildlife has many potential applications, including supplementary feeding stations, nestboxes, monitoring in the wild, as well as enrichment for wild animals in captivity.

Context. Capture–recapture sampling is one of the most commonly used methods for monitoring population demographics and is needed in a wide variety of studies where repeat sampling of individuals is desired. Although studies employing capture–recapture methods often assume unbiased sampling, it is well established that inherent capture biases can occur with these methods, including those related to baits. Reducing sources of sampling bias and augmenting recapture reliability is necessary for capture-dependent studies. However, few studies have examined the efficacy of baits on individuals with variable capture experience.

Aims. To investigate the use of an attractant-augmented bait in enhancing capture–recapture probabilities for snowshoe hares (Lepus americanus).

Methods. To examine the efficacy of different attractant-augmented bait types, a variety of baits were created, with bait preference tested on a captive hare. Because a strawberry jam-based bait was preferentially consumed (in comparison with other tested baits), the effectiveness of this attractant in enhancing capture–recapture rates was subsequently examined in wild hares, using paired live-trapping field trials (n = 6 trials).

Results. Live-trapping trials showed that although overall hare capture rates were not affected by the use of a jam-based bait, recaptures were 33.1% higher in capture-naïve individuals exposed to our attractant. This was not the case for hares with prior capture experience; such hares had an equal likelihood of being recaptured regardless of the bait type used.

Conclusions. The tested attractant improved recapture rates of capture-naïve hares.

Implications. Studies relying on high recapture rates should use methods that maximise recapture rates wherever possible, including the use of baits that may augment recaptures in capture-naïve animals.

Context. Understanding how organismal attributes influence sensitivity to environmental perturbations is a central theme in ecology and conservation. Certain traits, such as body size, habitat use, dietary preference and reproductive output are considered important determinants of animal species’ responses to the impacts of ecological disturbances. However, the general relationships between functional traits and post-disturbance responses by animals are not fully understood.

Aims. Our primary aim was to use a meta-analysis to evaluate the influence of species traits on variation in population abundances of squamate reptiles (i.e. lizards and snakes).

Methods. We extracted data from 107 original published studies, from which 1027 mean effect sizes of post-disturbance responses by 298 species were estimated. We examined short-term responses only (i.e. within 3 years since the most recent disturbance). A comprehensive range of disturbances was examined, such as habitat destruction, fragmentation, fire, and exotic-species invasions. We used Bayesian linear mixed-effect modelling (BLMM), utilising the Markov-chain Monte Carlo algorithm (MCMC) for the meta-regression. Specifically, we tested the influence of eight species traits (body size, diet, temporal activity pattern, sociality, reproductive mode, clutch size, habitat selection, and mean body temperature), along with disturbance type, in explaining variation in species-specific abundance responses of squamate reptiles post-disturbance.

Key results. Post-disturbance abundance responses of squamate species were significantly influenced by two parameters, namely, mean body temperature and clutch size. In general, significant positive responses post-disturbance were observed for species with higher mean body temperatures and a greater clutch size. The type of disturbance had no detectable influence on squamate abundances. The influence of random effects (heterogeneity among studies and species, and broad taxonomic identity) accounted for more of the model variation than did the fixed effects (species traits and disturbance type).

Conclusions. Certain species traits exerted some influence on the sensitivities of lizards and snakes to ecological disturbances, although the influence of random effects was very strong. Our findings are likely to be a result of the complexity and idiosyncratic nature of natural abundance patterns among animal species, in addition to the potential confounding effect of methodological differences among studies.

Implications. The present study is the first major quantitative synthesis of how species traits influence population-level responses of squamate reptiles to ecological disturbances. The findings can be used to guide conservation efforts and ecological management, such as by prioritising the efforts of mitigation on species that reproduce more slowly, and those with lower body temperatures.

Context. The invasive cane toad (Rhinella marina) has decimated populations of a keystone predator, the yellow-spotted monitor (Varanus panoptes), causing trophic cascades in Australian animal communities. Paradoxically, some V. panoptes populations coexist with toads. Demonstrating patterns in heterogeneous population-level impacts could reveal mechanisms that mediate individual effects, and provide managers with the ability to predict future impacts and assist in population recovery.

Aims. The aim of the present study was to search for spatial patterns of population resilience of V. panoptes to invasive cane toads.

Methods. Published literature, unpublished data, reports and anecdotal information from trained herpetologists were used to test the emerging hypothesis that resilient predator populations are mainly coastal, whereas non-resilient populations are mostly inland.

Key results. Post-toad invasion data from 23 V. panoptes populations supported the idea that toad impacts on V. panoptes were heterogeneous; roughly half the populations could be designated as resilient (n = 13) and half as non-resilient (n = 10). Resilient populations had longer times since toad invasion than did non-resilient populations (39 versus 9 years respectively), supporting the idea that some recovery can occur. Non-resilient populations were exclusively inland (n = 10), whereas resilient populations were split between inland (n = 5) and coastal (n = 8) populations. Resilient inland populations, however, were mainly confined to areas in which decades had passed since toad invasion.

Conclusions. The findings suggest that coastal V. panoptes populations fare much better than inland populations when it comes to surviving invading cane toads.

Implications. Unambiguous recovery of monitor populations remains undemonstrated and will require long-term population monitoring before and after toad invasion.

Context. The broad-toothed rat (Mastacomys fuscus; BTR) is distributed throughout south-eastern Australia, but its populations are restricted and dispersed. BTRs prefer cooler, wetter habitats and, as such, future climate change is projected to lead to further range reductions. However, recent changes in its distribution have not been well documented, and there is limited knowledge about the current occupancy and population size of the species in Victoria.

Aims. To evaluate recent historical changes in the distribution of BTRs in Victoria, and to test whether changes in distribution are correlated with climate and elevation.

Methods. We obtained all documented records of BTRs in the state before 1990 and used field notes and verbal descriptions to geo-reference their historical localities. We then used a repeated sampling design to resurvey all historically occupied sites with a geographic coordinate uncertainty of 4 km or less. We tested for the effects of climate and elevation on the persistence of BTRs.

Key results. We detected BTRs at 32 of 68 historical sites surveyed. Consistent with climate model predictions, site persistence was more likely to occur at sites of higher elevation and precipitation and less likely to occur at sites with a higher temperature. Minimum temperature of the coldest month was the single best predictor of persistence.

Conclusions. These results demonstrated a substantial decline in the persistence of BTRs at historical sites across Victoria and provided a benchmark for future monitoring and management efforts.

Implications. The decline of BTRs from historically occupied sites across Victoria is consistent with their listing as endangered in the state, and climate correlations suggest further declines, with projected climate change compounding other threats to the species such as introduced predators, feral herbivores, fire and land use. However, the status of BTRs in Victoria and understanding of the threats to their persistence are based on sparse data, highlighting the critical need for more effective monitoring of the species.