Context . Understanding the ecological impacts of the palm-oil industry on native fauna requires information on anthropogenic threats that may cause species decline or local extinction.

Aim . The main aim of the study was to assess wildlife deaths caused by illegal hunting, road accidents and introduced predators in established oil-palm landscapes in Peninsular Malaysia.

Methods . Between April and October 2009, we interviewed 362 oil-palm workers at 36 sites, including large industrial estates and semi-traditional smallholdings.

Key results . Our results showed that (1) illegal hunting by oil-palm workers in different oil-palm management systems was not statistically significant (P = 0.097), (2) native fauna were more often destroyed as pests in smallholdings than in conventional and eco-friendly plantation estates (P = 0.005), (3) non-local poachers conducted illegal activity more often in smallholdings than in conventional and eco-friendly plantation estates (P = 0.011), (4) road accidents were reported to kill more native fauna in conventional plantation estates than in smallholdings and eco-friendly plantation estates (P < 0.001) and (5) feral dogs were reported as killing more native fauna in eco-friendly plantation estates than in conventional plantation estates and smallholdings (P = 0.034).

Conclusion . In addition to the conversion of native forest to oil-palm monocultures, various other anthropogenic threats can have a substantial effect on wildlife in oil-palm landscapes.

Implications . To improve the conservation value of oil-palm landscapes, we recommend that palm-oil stakeholders should implement anti-poaching patrols, organise conservation programs to educate workers, reduce vehicle speeds on roads within oil-palm landscapes, and control local populations of feral dogs.

Context . Conservation of insectivorous bat populations requires appropriate management of foraging habitats and the prey resources they sustain. Endangered coastal saltmarsh communities support a diverse range of aquatic and terrestrial arthropods, including the saltmarsh mosquito (Aedes vigilax Skuse), an important vector of mosquito-borne viruses and a potentially important prey resource for insectivorous bats. Prey detectability by bats is considered to be limited with low-frequency echolocation, particularly in cluttered habitats, that may render abundant Ae. vigilax populations unavailable to some bat species.

Aims . To investigate relationships between availability of Ae. vigilax and non-mosquito prey, and the activity of foraging insectivorous bats in a range of coastal habitats.

Methods . We measured nightly bat activity and the abundance of prey (mosquito and non-mosquito) concurrently during neap and spring tides in saltmarsh, urban and forest habitats. Comparisons were made between tidal cycle and habitats, and relationships between bat activity and the abundance of prey were examined.

Key results . Whereas prey abundances were generally greatest in saltmarsh and forest habitats, bat activity was greatest in the forest habitat. However, proportional feeding activity was greatest in saltmarsh. Prey abundance was positively correlated with total bat activity only in the open saltmarsh, where an absence of clutter would maximise prey detectability and thus availability. Positive correlations between Ae. vigilax abundance and bat activity, across all habitats, were restricted to bats of the Vespadelus genus, which are small-sized bats that employ high-frequency echolocation suitable for detection of small prey along edges.

Conclusions . These findings suggest that Ae. vigilax may be an important prey resource for small, high-frequency echolocating bats capable of discerning small prey within cluttered forest as well as exploiting abundant prey in the open saltmarsh.

Implications . Small, high-frequency echolocating bats should be the focus of future studies investigating the importance of small prey, such as Ae. vigilax, to the diets of foraging bats.

Context . The processes of fragmentation, habitat loss, degradation and their combined effects are formidable threats to amphibian populations.

Aims . We evaluate the effect of three land use-type variables and nine landscape matrix quality factors on amphibian presence in four coffee agro-ecosystems and two cloud-forest fragments in central Veracruz, Mexico.

Methods . Each site was thoroughly searched using the visual-encounter survey technique along different trails in the most feasible microhabitats for detecting amphibians during four rainy seasons (2005, 2006, 2008 and 2009). Centred on the location where each amphibian species was first recorded, we established what we refer to as a buffer area within a radius of 1.5 km. A Co-Inertia mathematical model was used to determine which of the explanatory variables contributed to maintaining amphibian diversity. The landscape variables were landscape-quality index, open areas, canopy cover (low, intermediate, dense) at the matrix level, river, road and human population density and site size. Local variables were elevation, plant-structure and biological-impact indices.

Key results . During the study we recorded 1078 amphibians belonging to 26 species, 17 genera and 10 families. The variables explaining the composition of amphibian diversity were river and human population density, low canopy cover at the matrix level, elevation, site size and plant-structure index. Amphibian diversity increased as the structural complexity of the habitat increased, and the former was positively correlated with fragment size.

Conclusion . The present study indicated that coffee agro-ecosystems and the cloud-forest fragments in the region form a gradient in habitat quality and landscape variables that exert a differential influence on amphibian assemblages, and that each species responds uniquely to different variables.

Implications . Coffee agro-ecosystems and forest fragments cannot be seen as homogenous patches with a certain habitat quality, separate from the landscape matrix in which they are immersed. Stakeholders are not advised to rely on a single strategy to conserve the amphibian community, but rather should aim to maintain a heterogeneous landscape with forest fragments and coffee agro-ecosystems that have a complex vertical plant structure at the habitat level, especially in highly river-dense landscapes.

Context . Control of introduced pest species is based on the premise that there is a relationship between pest abundance and impact, but this relationship is rarely defined.

Aim . We investigated the impacts of introduced European hedgehogs (Erinaceus europaeus) on two species of small endemic skink (Oligosoma spp.) and flightless, nocturnal endemic orthopteran ground weta (Hemiandrus spp.), using an enclosure-based experimental manipulation of hedgehog density in tussock grasslands in the South Island of New Zealand.

Methods . We used capture–mark–recapture methods to estimate the densities of skinks before and after exposure to a range of hedgehog densities over a 3-month period and also compared changes in indices of abundance of skink demographic groups and ground weta.

Key results . Faecal analysis confirmed that hedgehogs consumed skinks and invertebrates in the enclosures. The proportional change between capture sessions in numbers of captured juvenile McCann’s skinks (O. maccanni) declined with increasing hedgehog density. Similarly, the proportional change in the numbers of ground weta encountered in pitfall traps showed a highly significant negative relationship with increasing hedgehog density. Total species abundances and numbers in other demographic skink groups did not change significantly in relation to hedgehog density. For overall skink abundance estimates, there was an apparent trend suggesting that changes in abundance were more negative with increasing hedgehog density, but this did not reach statistical significance for either skink species.

Conclusions . Our results confirmed that hedgehogs are important predators of small native fauna, but suggested that highly abundant prey populations may be buffered against significant impacts.

Implications . Less abundant prey and some demographic groups within populations, however, may be at significant risk from hedgehog predation.

Context . Wild cats (Felis spp.) are difficult to monitor because of their cryptic lifestyle and usually low numbers. Hair-snaring is a promising non-invasive method being used increasingly to estimate mammal populations.

Aims . Our aim was to carry out pilot trials of a simple hair-snare designed to capture hair from wild cats in arid environments.

Methods . Roughened wooden stakes were set at multiple sites on the crests of sand dunes and in swales in western Queensland, Australia, and in mostly sandy habitats of the Namib and Kalahari Deserts, Namibia. In Australia, stakes were sprayed with cat urine, extracts of catnip or valerian herbs as lures, or left untreated; in Namibia, alternate stakes were sprayed with a food lure of tuna emulsion oil. The stakes were checked for hair, usually daily, for 2–14 days, and the surrounding ground was inspected for tracks. Remote cameras also were used at some sites to confirm the identity of visitors to stakes.

Key results . In Australia, feral cats (Felis catus) were attracted to, and left hairs on, stakes sprayed with cat urine six times more frequently than to unsprayed stakes irrespective of whether snares were on dune crests or in swales, and showed no response to catnip or valerian. Tracks and photos showed that cats, dingoes or wild dogs (Canis lupus ssp.) and foxes (Vulpes vulpes) also approached and sniffed the stakes. In Namibia, F. catus, F. lybica and F. nigripes left hair on stakes, with deposition rates two and a half-fold higher at stakes with the food lure than without it. At least five other species of predators visited the hair-snare sites.

Conclusions . Simple wooden stakes provide a cheap and simple method of snaring hairs from wild cats, especially if used in conjunction with appropriate lures. Our results broadly support previous work, and extend the utility of the method to different Felis spp. in arid habitats.

Implications . Further research is needed on snares to investigate the seasonal efficiency of different lures. If DNA also is to be extracted to identify individuals, more work is needed to confirm that snares yield hair of sufficient quality to allow this.

Context . The ringed seal (Phoca hispida), a small phocid seal with a circumpolar Arctic distribution and a strong association with sea ice, occurs at the southern limit of its range in Hudson and James Bays: an area that experiences complete ice cover in winter and complete open water in summer. Because of the high seasonal variability in environmental conditions, it is expected that ringed seals experience seasonal changes in diet and foraging habitat, which will be reflected in body condition and biomarkers of stable isotopes and fatty acids.

Aims . The purpose of the present study was to investigate intra-annual variation in the feeding habits and body condition of the ringed seal.

Methods . Tissue samples and morphological measurements from south-eastern Hudson Bay ringed seals were obtained every month during the Inuit subsistence hunt from November 2009 to May 2011 (n = 192). Muscle samples were used for δ¹⁵N and δ¹³C stable isotope analysis, blubber was used for analysis of fatty acid composition, bodyweight and sculp weight were used to estimate percentage blubber, and lower right canines were used to determine age.

Key results . Fatty acid composition, δ¹⁵N, and δ¹³C varied significantly by season, suggesting seasonal changes in foraging habitat and diet. Variation in percentage blubber indicated that poorest body condition occurs following the molting and fasting period, followed by a gradual increase from late summer through fall, with the highest body condition occurring in time for freeze-up in December.

Key conclusions . Patterns of δ¹³C indicate pelagic feeding during the open-water season (August–December) when fat and energy stores are replenished, increased benthic foraging during the period of ice cover (January–May), followed by a period of fasting during the spring molt (June–July). Fatty acid composition suggested seasonal changes in diet that could include increased importance of pelagic fish in the fall during the period of positive energy balance.

Implications . The first continuous collection of ringed seal tissue samples provided a comprehensive seasonal pattern of biomarker composition, which is baseline data that have important applications for short-term management and ecology studies as well as long-term conservation and monitoring programs.

Context . Wildlife managers frequently use regulations to alter the preferred hunting strategies and outcomes of hunters. However, hunters can respond to changing social and resource conditions resulting from regulations in ways that can surprise wildlife managers.

Aims . The specific research questions were (1) how does the availability of licences (tags) required to harvest adult moose (Alces alces) relate to the success of hunters at filling these tags and (2) how do hunting pressure and the density of calf moose relate to the harvest rate of the calf population.

Methods . Information about hunters, harvest-related outcomes and moose abundance were estimated from social surveys and aerial inventories in 46 wildlife management units (WMUs) in northern Ontario, Canada. An information-theoretic approach was used to select regression models that predicted the average annual filling rate of tags for adult moose and for the average annual proportion of calf population harvested by hunters in the WMUs.

Key results . Tag filling rates were negatively and strongly associated with the availability of tags to hunters in the WMUs. The proportion of calf population harvested was positively related to hunting pressure and negatively related to the density of calf populations in the WMUs.

Conclusions . As tags became more scarce, hunters appeared to become more skilled at harvesting adult moose. As calf density declined, hunters harvested larger proportions of the population, indicating a possible inverse density-dependent relationship between abundance and harvest.

Implications . Understanding hunters and their actions and role within a larger social-ecological system are critical for helping to reduce the uncertainty of implementing regulations for managing wildlife. Without having this understanding, it is easy for managers to become trapped in situations where the intent of management actions is undermined by the abilities of hunters who respond to both changing social and resource conditions.

Context . Fire is a major ecological factor in many landscapes. Prescribed fires are often used in the management of vegetation for ecological values, wildlife habitat and reduction of risk of wildfire. However, debate continues over whether active fire management is beneficial to flora and fauna. Although bats comprise ∼20% of the world’s extant mammal fauna, they have been largely ignored in studies investigating ecosystem response to fire, especially in Australia.

Aims . In the present study, we aim to investigate the immediate responses of microbats to prescribed fires in a tropical eucalypt woodland.

Methods . We used a replicated paired experimental design, consisting of burned and unburned treatment and control sites, to investigate how bat activity and community structure change following a prescribed fire.

Key results . Total bat activity increased significantly following fire. Fire also resulted in changes in the bat species assemblage. Changes in community structure were driven by the following five species: Saccolaimus spp., Chalinolobus nigrogriseus, Chaerephon jobensis, Rhinolophus megaphyllus and unidentified Species c35. Activity of C. nigrogriseus, Saccolaimus spp., C. jobensis and Species c35 increased in the burned sites, whereas changes in the activity of R. megaphyllus were uncorrelated with the effects of fire.

Conclusions . The effect of fire on these species is consistent with flight patterns and habitat use; species with higher wing aspect ratios, such as Saccolaimus spp., which are capable of fast flight but with limited manoeuvrability, became more active in the open conditions created by fire.

Implications . The results of the present study suggest that prescribed fire as an environmental management tool may be beneficial to bats, at least in the short term, because it increases habitat suitability for a wider range of species.

Context . Monitoring populations of long-lived species requires continuous long-term efforts. This is especially applicable for species that have experienced declines range-wide.

Aims . Our study assessed the current status of a population of wild Macrochelys temminckii and compared the present results to those from a survey conducted nearly a decade ago.

Methods . Trapping in 2010–2011 was conducted on two creeks within the refuge, during the months of May–July. Capture data were compared with data collected by similar methods in 1997–2001.

Key results . The population structure of M. temminckii was dominated by juveniles, with few large adults or small juveniles detected and a missing size class was evident. Retrospective analysis of 1997–2001 data revealed that the population was likely to be in decline even then, despite high capture rates.

Conclusions . The M. temminckii population showed significant declines that indicated that the population had experienced stressors of unknown origin. The status of M. temminckii at the refuge is concerning, given the protection afforded this remnant population.

Implications . Short-term data from 1997–2001 indicated a healthy M. temminckii population, whereas longer-term data showed that the population has declined, resulting in significant demographic changes. Continued monitoring will be necessary to develop management recommendations and track the impact of implemented management practices. Longer-term monitoring of long-lived vertebrates is required to identify population trends.

Context . For the success of future conservation and management programs, it is necessary to better understand the resilience mechanisms of invasive species and their invasive potential. In this sense, the study of the effects that management actions have on their biological traits is essential.

Aims . The present study aimed to assess the effects of removal control on the abundance and biology of an isolated population of the top invasive fish Gambusia holbrooki (eastern mosquitofish).

Methods . Experimental removal control with traps and handnets was carried out on a population of mosquitofish inhabiting a small semiarid stream in south-eastern Spain. Mosquitofish were periodically captured for more than 3 years. Temporal variations in abundance, fish somatic condition and reproductive investment, percentage of mature females, size at maturity and population recruitment were analysed.

Key results . Individuals of the 1 age class increased their reproductive investment when population abundance was lower, thus increasing recruitment rate during the first months of the recruitment period. Individuals of the 0 age class were responsible for expanding the reproductive period in conditions of low fish abundance.

Conclusions . The mosquitofish population showed variations of reproductive parameters that could indicate a compensatory density-dependent phenotypic response under diminished abundance conditions. However, its removal by the constant use of a combination of active and passive capture methods, reinforced by increased extraction effort according to its local biology, has led to an eradication of the population. The target mosquitofish population showed distinct ecological features that may have contributed to the effectiveness of local control, namely, low initial fish density, isolation in a headwater stretch and the prevalence of individuals in sunlit shallow ponds.

Implications . The compensatory mechanisms of this invasive species in low-density conditions should be considered in the design of management programs. Moreover, further research into removal control methods for mosquitofish or similar species is also needed.