The delimitation of evolutionarily significant units (ESUs) frequently results in controversy, but prioritising populations with evolutionary independence is essential for effective in situ conservation management. The American manatee (Trichechus manatus) is distributed along subtropical and tropical coastal waters from Florida (USA) to Alagoas (Brazil), and two subspecies are traditionally recognised, namely, T. m. latirostris, restricted to the Florida peninsula, and T. m. manatus, found in the remaining areas. However, this subspecific classification is not supported by genetic and morphologic evidence, which, rather, recognises two deeply differentiated populations or ESUs called Atlantic (Brazil) and Caribbean (from Venezuela to Florida). In this viewpoint paper, we compare both intraspecific divisions of T. manatus and the conservation implications. First, we used all available mtDNA evidence to test the genealogical clustering of the two American manatee ESUs by using a tree-based coalescent method. Second, we have used different models under a coalescent framework to estimate the historic gene flow among manatee populations. The analysis of the spatial distribution of mtDNA clusters confirmed the existence of the two suggested ESUs, rather than the two claimed subspecies. Furthermore, the best model to explain historic migration indicates that Brazilian manatees belong to an isolated population, whereas Florida and Caribbean populations are connected by more recent gene flow. These results have confirmed that T. manatus of the Caribbean, Gulf of Mexico and Florida belong to the same deme or Caribbean ESU, and the relatively isolated population inhabiting the Atlantic coast of Brazil belongs to the Atlantic ESU. Furthermore, both ESUs are separated by an interspecific hybrid zone (with the Amazonian manatee) located around the mouth of the Amazon River towards the Guianas coastline. The subdivision of two ESUs is also highly supported by karyotypic, morphological and ecological data, and is in clear disagreement with the traditional subspecies designations and the IUCN priorities, which manages Brazilian manatees as part of the Antillean manatee subspecies (T. m. manatus). Rather, Brazilian manatees should be considered as a full priority for conservation and require further taxonomic research; because of their deep history of isolation, they present high genetic and morphologic differentiation from all other American manatees.

Context. The Cerrado is a Global Biodiversity Hotspot as well as Brazil’s main frontier for large-scale agriculture and livestock production, making it one of the most threatened biomes in the country. Brazil is one of the biggest consumers of pesticides in the world and allows the use of chemicals that are banned in many other countries due to their adverse health effects in a wide range of species, including humans.

Aims. This study aimed to assess pesticide and metal exposure of the lowland tapir – a threatened, large herbivorous mammal – to support future studies of the role of these chemicals in tapir health, survivorship, and population viability.

Methods. Foot pad, proboscis, stomach contents, liver, bone, and nail samples were obtained from tapir carcasses found along highways (n = 87). (i) Atomic absorption spectrophotometry (AAS) was used to detect metals in bone, nail and liver tissue; (ii) gas chromatography – nitrogen phosphorous detector (GC-NPD) to detect organophosphates in liver and skin; and (iii) high performance liquid chromatography – ultraviolet (HPLC-UV) to detect pyrethroids and carbamates in stomach contents.

Key results. Two carbamates (aldicarb and carbaryl), three organophosphates (diazinon, malathion, and mevinphos), two pyrethroids (deltamethrin and permethrin), and two toxic metals (cadmium and lead) were detected in different tapir tissue samples, some at concentrations high enough to cause adverse health effects. In 90% of roadkill tapirs that were subjected to a full post-mortem examination (n = 25), macroscopic alterations of liver and/or kidney tissue were observed.

Conclusions. This study provides the first report to date of the detection of pesticides and metals in lowland tapirs.

Implications. Some of the reported pesticide concentrations exceed environmental safety thresholds. Consequently, results from this study raise concerns over potential adverse health effects in tapirs that could lead to population level impacts, thus requiring further investigation.

Context. Most of the effort dedicated to the conservation of biodiversity in the European Union is applied through the establishment and maintenance of the Natura 2000 network, the world’s most extensive network of conservation areas. European Member State must actively manage these sites and report the state of the species listed in the Annexes of the Habitat and Birds Directives. Fulfilling these duties is a challenging task, especially when money available for conservation is limited. Consequently, how to optimise the use of the available economic resources is a primary goal for reserve managers.

Aims. In the present study, we focussed on data-sharing, and we analysed whether data-sharing among institutions may boost the performance of habitat suitability models (HSMs).

Methods. We collected presence data about three species of reptiles in three different protected areas of northern Italy. Then, we built HSMs under the following two different data-sharing policies: data-sharing of species’ occurrence among the different managers of the protected areas, and not sharing the occurrence data among the different managers. To evaluate how sharing the occurrence data influences the reliability of HSMs in various situations, we compared model performances under several sampling-effort levels.

Key results. Results show that data-sharing is usually the best strategy. In most cases, models built under the data-sharing (DS) strategy showed better performance than did data-un-sharing (DU) models. The data-sharing strategy showed advantages in model performance, notably at low levels of sampling effort.

Conclusions. Overcoming administrative barriers and share data among different managers of protected areas allows obtaining more biologically meaningful results.

Implications. Data-sharing among protected areas could allow improving the reliability of future management actions within the Natura 2000 network.

Context. Forest fire activity is expected to increase in many parts of the globe over the course of the 21st century, with corresponding potential for heightened levels of proximate and ultimate threats to avian diversity. Landscape-scale investigations of the responses of birds in locations where current extreme fire regimes represent those expected in the future provide opportunities to identify potentially vulnerable species in advance. Autonomous acoustic recorders are well suited to survey birds in the typically large and remote natural areas with low accessibility required for these types of studies, because they offer cost-effective and relatively safe options for obtaining reliable data.

Aims. The present study aimed to optimise survey using acoustic recorders to achieve a satisfactory assessment of montane dry sclerophyll forest bird assemblages using these devices. Survey completeness, or the number of species detected as a percentage of total species, was used as a metric to gauge survey suitability.

Methods. Acoustic recorders were deployed in 10 ridge-top forest sites in the Blue Mountains, south-eastern Australia. Extensive field recordings were processed by an analyst, with species detected by their calls recorded in a series of 20-min samples. A results-based approach, incorporating a stopping rule that established when to conclude sampling at a site, was applied to the data. The results guided the target survey completeness and sampling effort levels assigned to a set of fixed-effort survey methods, which were subsequently evaluated.

Key results. The optimal survey method involved using recordings from five 20-min sampling periods immediately following dawn for 2 days, achieving an average survey completeness level of 69%.

Conclusions. The optimal survey method can obtain results that are suitable for many types of studies involving assessments of bird assemblages, because the method can detect all common and moderately common species in assemblages, plus a fair proportion of rare species.

Implications. The present study has systematically developed an effective method of using autonomous acoustic recorders to research and monitor montane bird assemblages in fire-prone dry sclerophyll forests. This methodological approach may also be applied in systems subject to altered patterns of flood, storm or other extreme weather under climate change.

Context. Bird–aircraft collisions impose an economic cost and safety risk, yet ecological studies that inform bird hazard management are few, and to date no study has formally compared species’ strike profiles across airports. In response to strike risks, airports have implemented customised management on an airport-by-airport basis, based on the assumption that strike risk stems from prevailing local circumstances. We tested this assumption by comparing a decade of wildlife–aircraft strikes at three airports situated in the same bioregion (likely to have similar fauna) of Victoria, Australia.

Aim. To compare the assemblage of wildlife struck by aircraft at three major airports in the same bioregion.

Method. Standardised wildlife strike data were analysed from three airports (Avalon, Melbourne and Essendon Airports), in the Victorian Volcanic Plains bioregion, central Victoria, Australia. Ten discrete 1-year sampling periods from each airport were compared, spanning the period 2009–19. Bird data were comparable, and data on mammals were considered less reliable, so emphasis was placed on birds in the present study.

Results. In total, 580 bird strikes were analysed, with the most commonly struck species being Australian magpie (Cracticus tibicen; 16.7%), Eurasian skylark (Alauda arvensis; 12.2%), Australian pipit (Anthus australis; 12.1%), masked lapwing (Vanellus miles; 5.9%), nankeen kestrel (Falco cenchroides; 5.0%), house sparrow (Passer domesticus; 4.8%), welcome swallow (Hirundo neoxena; 4.3%) and tree martin (Petrochelidon nigricans; 4.0%). The assemblage of birds struck by aircraft over the decade of study differed between airports. The most commonly struck species drove the assemblage differences between airports.

Conclusions and implications. In the present study system, airports experienced discrete strike risk profiles, even though they are in the same bioregion. The airports examined differed in terms of air traffic movement rates, aircraft types, landscape context and bird hazard management effort. Given that strike risks profiles differ among airports, customised management at each airport, as is currently the case, is supported.

Context. A coyote-caused human fatality in Cape Breton Highlands National Park of Canada (CBHNPC) occurred in 2009. Because CBHNPC is federally protected, rangers have a limited number of management options for dealing with human–coyote conflict. The park initiated the present study to understand the publics’ acceptance of coyotes.

Aims. This article examined relationships between each of four independent variables (respondent type (resident vs visitor), sex, age, education) and each of four dependent variables (knowledge, attitude, two emotions) related to coyotes in CBHNPC. Researchers have repeatedly suggested that demographics are related to cognitions and emotions toward wildlife. Managers can use demographic findings to target education campaigns to specific stakeholders.

Methods. Survey data were obtained from (a) residents living around CBHNPC (n = 556, response rate = 70%), and (b) visitors hiking two popular trails in CBHNPC (n = 443, response rate = 60%).

Key results. All four independent variables were related to knowledge. Visitors were more knowledgeable about coyotes than were residents. Females were more knowledgeable than were males. Younger respondents were more knowledgeable than were older individuals. All education categories differed from each other. Findings for the attitude construct were similar. Residents held negative attitudes toward coyotes, whereas visitors were slightly positive. Males and females both held negative attitudes. The youngest age category held a positive attitude, whereas the oldest group was the most negative. Respondents with a high-school degree had a negative attitude; those with a college degree held a positive attitude. For the first emotion concept, residents were more emotional than were visitors. Males were more emotional than were females, and high-school graduates were more emotional than were college graduates. For the second emotion, there were statistical differences between residents and visitors, as well as between males and females. However, age and education were not related to this scenario.

Conclusions. Although there were statistical differences for 13 of 16 tests, over 80% of the effect sizes were minimal and there were interaction effects among the four demographic variables.

Implications. Findings highlighted complexities managers should consider when designing communication strategies aimed at influencing stakeholders’ knowledge of and attitudes and emotions toward wildlife.

Context. Understanding what constitutes high-quality habitat for threatened species is critical for conservation management planning. The endangered northern quoll (Dasyurus hallucatus) has experienced an uneven range contraction among habitat types. Once common across multiple habitats of northern mainland Australia, declining populations have now contracted to rocky escarpments.

Aim. The island refuge of Groote Eylandt, Northern Territory, Australia, has not experienced the declines as seen on mainland Australia. Here, northern quolls persist in both rocky escarpment and savanna woodland, which provides a rare opportunity to investigate the habitat quality of rocky escarpments and savanna woodland for the northern quoll.

Methods. Northern quolls (n = 111) were trapped in both rocky escarpment (n = 61) and savanna woodland (n = 50) habitats before the breeding season (May). We conducted body condition assessment, scat analysis, and measured trophic niche breadth of individuals occupying each habitat type.

Key results. Female quolls occupying rocky escarpments exhibited a lower body condition than did quolls occupying savanna woodland. Quolls from rocky escarpments consumed a significantly higher proportion of mammals and fed within a narrower dietary niche than did those occupying savanna woodland.

Conclusions. Quolls had adapted to the dietary resources available within each habitat type, suggesting that the lack of quolls in savanna woodland on the mainland is due to factors other than availability of dietary resources.

Implications. Groote Eylandt is of critical conservation significance, where high numbers of northern quolls exist in both rocky escarpment and savanna woodland habitats. For population viability on the mainland, managing threats such as feral predators and inappropriate fire regimes in savanna woodland, particularly those surrounding rocky escarpment, should be prioritised.

Context. The pale field-rat (Rattus tunneyi) is a small native rat that formerly had a wide distribution throughout Australia. It has suffered substantial range contraction since European settlement and is now largely absent from arid and semiarid Australia. In this biome, it was known to persist only at two Western Australian locations: Edel Land, on the south-western shore of Shark Bay, and islands off the Pilbara coast.

Aims. We aimed to establish the extent of the species range at Edel Land, its habitat preference, the temporal stability of its populations with respect to rainfall, and threats to its persistence.

Methods. We trapped at 54 sites to establish distribution and habitat preference, and re-trapped four of these sites at which R. tunneyi was present in each season for 2.5 years to establish trends in abundance.

Key results. Trapping resulted in the capture of 45 R. tunneyi individuals across 17 of 54 sites (4104 trap-nights; 1.1% capture success). Rattus tunneyi typically occupied localised areas of dense shrubland, often in habitats with free water or near-surface moisture from drainage from high dunes allowing denser and taller vegetation and, at some sites, year-round growth of grasses or rushes. Regular re-trapping of four sites in each season (2002 – 2004) suggested a declining population, probably owing to a sequence of dry years.

Key conclusions. Rattus tunneyi at Shark Bay occurred only in localised mesic refuges, apparently dependent on seepage from high dunes generated by major inputs of rainfall from infrequent cyclones or sequences of high-rainfall years.

Implications. This isolated population is likely to be threatened by browsing by feral goats, opening up otherwise densely vegetated habitats of refuge areas, and their trampling of R. tunneyi burrows; by the depletion of grasses from herbivory by European rabbits; and by the long-term impact of a drying climate. It is unlikely to persist without effective on-going management, particularly of the goat population.

Context. Species translocations are used in conservation globally. Although harvest for translocation may have negative impacts on source populations, translocation programs rarely explore ways of minimising those impacts. In fluctuating source populations, harvest timing may affect its impact because population size and trajectory vary among years.

Aims. We explored whether the timing and scale of harvest can be altered to reduce its impact on a fluctuating source population of Mallee Emu-wrens, Stipiturus mallee; an endangered passerine in south-eastern Australia. Mallee Emu-wren populations fluctuate with ∼5–10-year drought–rain cycles.

Methods. We used population viability analysis (PVA) to compare the impact of five harvest scales (no harvest, 100, 200, 300 or 500 individuals) under three population trajectories (increasing, stable or decreasing) and two initial population sizes (our model-based estimate of the population size and the lower 95% confidence interval of that estimate). To generate a model-based estimate of the population size, we surveyed 540 sites (9 ha), stratified according to environmental variables known to affect Mallee Emu-wren occurrence. We used an information-theoretic approach with N-mixture models to estimate Mallee Emu-wren density, and extrapolated results over all potential habitat.

Key results. We estimate that in spring 2019, the source population consisted of 6449 individuals, with a minimum of 1923 individuals (lower 95% confidence interval). Of 48 harvest scenarios, only seven showed no impact of harvest within 5 years (15%). Those seven all had increasing population trajectories and carrying capacity set to equal initial population size. Twenty-six populations showed no impact of harvest within 25 years (54%). These were either increasing populations that had reached carrying capacity or decreasing populations nearing extinction.

Conclusions. Initial population size, carrying capacity, harvest scale and population trajectory were all determinants of harvest impact. Given the importance of carrying capacity, further research is required to determine its role in the Mallee Emu-wren source population.

Implications. Harvesting Mallee Emu-wrens after high-rainfall years will have the least impact because source populations are likely to be large with increasing trajectories. For fluctuating source populations, flexibility in the timing of harvest can reduce its impact and should be considered during translocation planning.

Context. Invasive species are a major cause of biodiversity loss across much of the world, and a key threat to Australia’s diverse reptile fauna. There has been no previous comprehensive analysis of the potential impact of the introduced European red fox, Vulpes vulpes, on Australian reptiles.

Aims. We seek to provide an inventory of all Australian reptile species known to be consumed by the fox, and identify characteristics of squamate species associated with such predation. We also compare these tallies and characteristics with reptile species known to be consumed by the domestic cat, Felis catus, to examine whether predation by these two introduced species is compounded (i.e. affecting much the same set of species) or complementary (affecting different groups of species).

Methods. We collated records of Australian reptiles consumed by foxes in Australia, with most records deriving from fox dietary studies (tallying >35 000 samples). We modelled presence or absence of fox predation records against a set of biological and other traits, and population trends, for squamate species.

Key results. In total, 108 reptile species (∼11% of Australia’s terrestrial reptile fauna) have been recorded as consumed by foxes, fewer than that reported for cats (263 species). Eighty-six species have been reported to be eaten by both predators. More Australian turtle species have been reported as consumed by foxes than by cats, including many that suffer high levels of predation on egg clutches. Twenty threatened reptile species have been reported as consumed by foxes, and 15 by cats. Squamate species consumed by foxes are more likely to be undergoing population decline than those not known to be consumed by foxes. The likelihood of predation by foxes increased with squamate species’ adult body mass, in contrast to the relationship for predation by cats, which peaked at ∼217 g. Foxes, but not cats, were also less likely to consume venomous snakes.

Conclusions. The two introduced, and now widespread, predators have both compounding and complementary impacts on the Australian reptile fauna.

Implications. Enhanced and integrated management of the two introduced predators is likely to provide substantial conservation benefits to much of the Australian reptile fauna.