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Arid rangelands are degraded worldwide, suffering vegetation transformation, soil erosion, introductions, and extinctions. Wild deserts is restoring a desert ecosystem in Sturt National Park, New South Wales, Australia (35,000 ha), eradicating or controlling introduced animals, managing native herbivores, and reintroducing regionally extinct mammals. We describe a Strategic Adaptive Management Plan for restoration of this desert ecosystem, including a vision, model of ecosystem processes, stakeholder input, a hierarchy of objectives linked to triggers and their management actions, producing outcomes and outputs. Our management treatments included two “no restoration” areas and three “restoration” areas. The latter include two exclosures (each 2,000 ha), free of introduced animals (foxes, cats, rabbits), with previously abundant kangaroos removed and regionally extinct mammals to be reintroduced. The third management treatment is a Wild Training Zone (10,400 ha), with introduced animals and kangaroos managed at low levels, using innovative methods, improving survivorship and avoidance behavior of reintroduced mammals to introduced predators. These measures will allow populations of threatened animals to establish, initially in the exclosures, then the Wild Training Zone and potentially more widely. Our strategic adaptive management planning approach is generic and implementable for any natural resource management project, providing explicit steps and processes that track and report transparently on outcomes, fostering learning by doing.

Understanding and conserving mobile species presents complex challenges, especially for animals in stochastic or changing environments. Nomadic waterbirds must locate temporary water in arid biomes where rainfall is highly unpredictable in space and time. To achieve this they need to travel over vast spatial scales and time arrival to exploit pulses in food resources. How they achieve this is an enduring mystery. We investigated these challenges in the colonial-nesting Banded Stilt (Cladorhynchus leucocephalus), a nomadic shorebird of conservation concern. Hitherto, Banded Stilts were hypothesized to have only 1-2 chances to breed during their long lifetime, when flooding rain fills desert salt lakes, triggering mass-hatching of brine shrimp. Over 6 years, we satellite tagged 57 individuals, conducted 21 aerial surveys to detect nesting colonies on 14 Australian desert salt lakes, and analyzed 3 decades of Landsat and MODIS satellite imagery to quantify salt-lake flood frequency and extent. Within days of distant inland rainfall, Banded Stilts flew 1,000-2,000 km to reach flooded salt lakes. On arrival, females laid over half their body weight in eggs. We detected nesting episodes across the species' range at 7 times the frequency reported during the previous 80 years. Nesting colonies of thousands formed following minor floods, yet most were subsequently abandoned when the water rapidly evaporated prior to egg hatching. Satellite imagery revealed twice as many flood events sufficient for breeding-colony initiation as recorded colonies, suggesting that nesting at remote sites has been underdetected. Individuals took risk on uncertain breeding opportunities by responding to frequent minor flood events between infrequent extensive flooding, exemplifying the extreme adaptability and trade-offs of species exploiting unstable environments. The conservation challenges of nest predation by overabundant native gulls and anthropogenic modifications to salt lakes filling frequencies require investigation, as do the physiological and navigational mechanisms that enable such extreme strategies.

Funding for species conservation is insufficient to meet the current challenges facing global biodiversity, yet many programs use expensive single-species recovery actions and neglect broader management that addresses threatening processes. Arid Australia has the world's worst modern mammalian extinction record, largely attributable to competition from introduced herbivores, particularly European rabbits (Oryctolagus cuniculus) and predation by feral cats (Felis catus) and foxes (Vulpes vulpes). The biological control agent rabbit hemorrhagic disease virus (RHDV) was introduced to Australia in 1995 and resulted in dramatic, widespread rabbit suppression. We compared the area of occupancy and extent of occurrence of 4 extant species of small mammals before and after RHDV outbreak, relative to rainfall, sampling effort, and rabbit and predator populations. Despite low rainfall during the first 14 years after RHDV, 2 native rodents listed by the International Union for Conservation of Nature (IUCN), the dusky hopping-mouse (Notomys fuscus) and plains mouse (Pseudomys australis), increased their extent of occurrence by 241-365%. A threatened marsupial micropredator, the crest-tailed mulgara (Dasycercus cristicauda), underwent a 70-fold increase in extent of occurrence and a 20-fold increase in area of occupancy. Both bottom-up and top-down trophic effects were attributed to RHDV, namely decreased competition for food resources and declines in rabbit-dependent predators. Based on these sustained increases, these 3 previously threatened species now qualify for threat-category downgrading on the IUCN Red List. These recoveries are on a scale rarely documented in mammals and give impetus to programs aimed at targeted use of RHDV in Australia, rather than simply employing top-down threat-based management of arid ecosystems. Conservation programs that take big-picture approaches to addressing threatening processes over large spatial scales should be prioritized to maximize return from scarce conservation funding. Further, these should be coupled with long-term ecological monitoring, a critical tool in detecting and understanding complex ecosystem change.

Parental care strategies have been widely investigated in shorebirds that undertake long-distance regular migrations. In contrast, virtually nothing is known of the parental care of nomadic, opportunistically breeding shorebirds, although the irregular and short-lived nature of their breeding potentially accentuates the trade-offs between investment in successive clutches and between the sexes. We investigated the incubation behaviour of the nomadic, opportunistically breeding Banded Stilt (Cladorhynchus leucocephalus). Seven nests, filmed continuously with day–night cameras over 2–7 days, revealed that both sexes contributed to incubation, with males apparently the sole carer during hatching and early brood-rearing; this is a possible adaptation, which enables females to quickly produce a second clutch if favourable conditions persist. All incubator changeovers occurred after dark; incubation shifts averaged 44.8 ± 10.9 (s.e.m.) h (n = 11, 17.5–139.6 h), the longest recorded for any shorebird. Incubation constancy averaged 96.5%; this high value is possibly an adaptation to high predation and the need for rapid embryonic development in the face of ephemeral resources for breeding. Long incubation shifts may be explained by extended foraging trips to distant areas of the partially inundated salt-lake surface, where food resources had been concentrated by wind-driven water movement.

The Flock Bronzewing Phaps histrionica has declined significantly and undergone a northward range contraction in inland Australia since European settlement. In the southern parts of its range, including central northern South Australia, it is uncommonly recorded during times of significant ephemeral vegetation response, triggered by sustained above-average rainfall. In late 2013, while core habitats in Queensland were in extended drought and much of arid South Australia received below-average rainfall, an area of ~10 000 km2 between Roxby Downs and Lake Eyre South supported tens of thousands of Flock Bronzewings, with evidence of widespread successful breeding during September and October and contemporary range expansions of 150 km to the south and west. Through a network of local pastoralists, mining workers and biologists we collated ˃80 field observations from >40 observers across this region. Direct evidence of predation by Cats Felis catus was detected at a nest-site and in the stomach of a cat shot in the area. Seeds of annual shrubs Trichodesma and Phyllanthus species dominated the crop contents of two dead fledgling Bronzewings that were collected opportunistically. Although the Flock Bronzewing is well known for its irruptive nature, the magnitude and southerly extent of this sustained irruption are unprecedented in the literature and in the living memory of local observers. This event exemplifies the remarkable ability of arid-adapted birds to locate and exploit localised productive habitat within vast dynamic and stochastic landscapes, in this case recruiting new individuals to the population despite widespread unfavourable conditions within their core range.

Understanding and conserving mobile species presents complex challenges, especially for animals in stochastic or changing environments. Nomadic waterbirds must locate temporary water in arid biomes where rainfall is highly unpredictable in space and time. To achieve this they need to travel over vast spatial scales and time arrival to exploit pulses in food resources. How they achieve this is an enduring mystery. We investigated these challenges in the colonial-nesting Banded Stilt (Cladorhynchus leucocephalus), a nomadic shorebird of conservation concern. Hitherto, Banded Stilts were hypothesized to have only 1-2 chances to breed during their long lifetime, when flooding rain fills desert salt lakes, triggering mass-hatching of brine shrimp. Over 6 years, we satellite tagged 57 individuals, conducted 21 aerial surveys to detect nesting colonies on 14 Australian desert salt lakes, and analyzed 3 decades of Landsat and MODIS satellite imagery to quantify salt-lake flood frequency and extent. Within days of distant inland rainfall, Banded Stilts flew 1,000-2,000 km to reach flooded salt lakes. On arrival, females laid over half their body weight in eggs. We detected nesting episodes across the species' range at 7 times the frequency reported during the previous 80 years. Nesting colonies of thousands formed following minor floods, yet most were subsequently abandoned when the water rapidly evaporated prior to egg hatching. Satellite imagery revealed twice as many flood events sufficient for breeding-colony initiation as recorded colonies, suggesting that nesting at remote sites has been underdetected. Individuals took risk on uncertain breeding opportunities by responding to frequent minor flood events between infrequent extensive flooding, exemplifying the extreme adaptability and trade-offs of species exploiting unstable environments. The conservation challenges of nest predation by overabundant native gulls and anthropogenic modifications to salt lakes filling frequencies require investigation, as do the physiological and navigational mechanisms that enable such extreme strategies.

Summary The impacts of uncapped, abandoned mining shafts on small vertebrate species were investigated by monitoring numbers of fauna falling into opal prospecting shafts near Coober Pedy, in the far north of South Australia. Catching devices made from 10 L buckets were installed in the top of 43 shafts and checked regularly by local community members for a total of 10 840 trap nights over a 13-month period. A total of 190 individual reptiles of 18 species were captured in this manner after falling into shafts, including the nationally vulnerable Bronzeback Legless Lizard (Ophidiocephalus taeniatus). While the tops of these shafts resemble conventional pitfall traps used in scientific monitoring and therefore readily ‘trap’ ground-fauna, they may be over 30 m deep and are permanently open. Capture rates in this study, calculated at 4.1 reptiles/shaft/year, highlight the potential impact of the similar shafts that remain uncapped in the Coober Pedy opal fields, roughly estimated to be anywhere from 1 to 2 million shafts. The inferred total number of captures from these shafts may represent 10–28 million reptiles/year or an equivalent of 25–72 tonnes of biomass. The results highlight the potential threat that uncapped shafts may pose to Bronzeback Legless Lizard populations in this area and suggest that they may also have major impacts on other small vertebrate fauna in the Coober Pedy area and in other similar opal mining areas.

Species reintroductions into predator-controlled areas are an increasingly used conservation tool. Typically, ecological outcomes of such projects (e.g. recruitment, predation) are the focus but seldom necessary legislative, policy, social and institutional processes required for establishing large projects. This particularly applies to protected areas, managed by governments for conservation. Reintroductions are recommended for a third of threatened Australian vertebrates, with the New South Wales Government boldly embarking on a 2013 initiative to return locally extinct mammals to three protected areas. We detail the legislative, policy, social and institutional processes required for one of these sites, Wild Deserts, in Sturt National Park. Seven locally extinct species, including the greater bilby (Macrotis lagotis), western barred bandicoot (Perameles bougainville), golden bandicoot (Isoodon auratus), greater stick-nest rat (Leporillus conditor), crest-tailed mulgara (Dasycercus cristicauda), western quoll (Dasyurus geoffroii) and burrowing bettong (Bettongia lesueur) will be reintroduced into two exclosures. The scale of the project required identification of an appropriate location, satisfaction of statutory requirements for major infrastructure in a national park, assessments of potential ecological costs and benefits, engagement of the national park agency and other stakeholders (Traditional Owners, other government agencies, neighbours), and staff training to meet government agency requirements. We outline the resourcing, costs and benefits of such a project on government-managed land along with lessons learnt for similar large-scale restoration and reintroduction projects. Future projects would benefit from understanding legislative and policy frameworks and the need for transparency, while maximising efficiencies.

Populations of many arid-zone rodents are known to fluctuate dramatically in response to the boom–bust cycles of the dynamic landscapes in which they occur. This constrains their study, particularly efforts to determine the location and functioning of important refuge areas. The nationally vulnerable plains mouse (Pseudomys australis) undergoes dramatic population changes in response to rainfall and associated resource abundance. At low population density during resource shortages, the species can be present yet undetectable by conventional trapping methods. We piloted the use of hair tubes as an alternative to trapping, trialling designs effective in detecting P. australis. Baited 25-mm- or 32-mm-diameter × 200-mm-long tubes with double-sided cloth tape in the entrance were effective in collecting P. australis hair. Each of the 21 detections of the species’ presence through hair tubes was confirmed using other methods. Hair tubes effectively detected the species, including during times when Elliott trapping yielded low capture rates and observational techniques failed to detect them. Hair tubes may present a time- and cost-efficient tool for determining the presence of P. australis and other cryptic small mammals in remote arid landscapes.

Context Trapping of small vertebrates during their active hot summer periods is vital for conservation and impact assessment studies. Animal Ethics Committees (AECs) protect wildlife by enforcing arbitrary but restrictive temperature limits for trapping. Aims Empirical data were gathered on the temperatures reached in different trap configurations to inform pragmatic ethical guidelines. Methods Temperature was measured inside small vertebrate traps at two Australian arid zone sites to generate data on the thermal consequences of: (1) trap design and external shading; (2) provision of protective refuge substrates; and (3) timing of trap clearing. Key results Shading and increased trap depth significantly reduced temperatures within pitfall traps. A conservative stressful upper temperature limit of 36°C was never exceeded inside deep, shaded, narrow pitfall traps at one study site and only between 1100 and 1300 hours on 3 days at the hotter site, despite ambient temperatures reaching over 42°C. By contrast, potentially lethal upper temperatures were reached in wider, shallower bucket pit traps on most days at both sites, even when optimal shading and refuge substrates were employed. Deployment of surface traps under vegetation and with additional shading significantly reduced maximum temperatures experienced. Temperatures inside shaded Elliott and funnel traps generally tracked ambient air temperatures and thus typically exceeded conservative threshold temperatures between 0700 and 1900 hours when ambient temperatures exceeded 36°C. Conclusions Temperatures experienced in optimal deep, shaded traps when ambient temperatures exceeded 40°C were 31°C lower than surface temperatures and similar to temperatures recorded at 20 cm below the soil surface, where many species would typically take refuge at these times. Implications Data suggest that deep (60 cm), narrow pitfall traps with elevated lids for shade and shelter substrate inside should enable trapping to be conducted safely in the study region during summer (December to February). This is even the case in extremely hot weather, as long as trapped animals are removed within 4 h of sunrise. Ecophysiological studies of thermal tolerance within optimum trap arrangements revealed by the present study will allow field ecologists and AECs to develop informed site-specific trapping protocols.

Funding for species conservation is insufficient to meet the current challenges facing global biodiversity, yet many programs use expensive single-species recovery actions and neglect broader management that addresses threatening processes. Arid Australia has the world's worst modern mammalian extinction record, largely attributable to competition from introduced herbivores, particularly European rabbits (Oryctolagus cuniculus) and predation by feral cats (Felis catus) and foxes (Vulpes vulpes). The biological control agent rabbit hemorrhagic disease virus (RHDV) was introduced to Australia in 1995 and resulted in dramatic, widespread rabbit suppression. We compared the area of occupancy and extent of occurrence of 4 extant species of small mammals before and after RHDV outbreak, relative to rainfall, sampling effort, and rabbit and predator populations. Despite low rainfall during the first 14 years after RHDV, 2 native rodents listed by the International Union for Conservation of Nature (IUCN), the dusky hopping-mouse (Notomys fuscus) and plains mouse (Pseudomys australis), increased their extent of occurrence by 241-365%. A threatened marsupial micropredator, the crest-tailed mulgara (Dasycercus cristicauda), underwent a 70-fold increase in extent of occurrence and a 20-fold increase in area of occupancy. Both bottom-up and top-down trophic effects were attributed to RHDV, namely decreased competition for food resources and declines in rabbit-dependent predators. Based on these sustained increases, these 3 previously threatened species now qualify for threat-category downgrading on the IUCN Red List. These recoveries are on a scale rarely documented in mammals and give impetus to programs aimed at targeted use of RHDV in Australia, rather than simply employing top-down threat-based management of arid ecosystems. Conservation programs that take big-picture approaches to addressing threatening processes over large spatial scales should be prioritized to maximize return from scarce conservation funding. Further, these should be coupled with long-term ecological monitoring, a critical tool in detecting and understanding complex ecosystem change.

In contrast to well-studied Northern Hemisphere birds with spatially and temporally predictable seasonal migrations, waterbirds in desert biomes face major challenges in exploiting stochastic, rich, yet short-lived resource pulses in vast arid landscapes, leading to the evolution of nomadic behaviour. An extreme example is the banded stilt ( Cladorhynchus leucocephalus ), an opportunistic colonial breeder at remote inland salt lakes after infrequent rain events. Using satellite telemetry on 21 birds (tracked for a mean of 196.2 days), we reveal extensive, rapid and synchronized movement among individuals to and from salt lakes. Two birds left coastal refugia for the inland following rain, flying 1000–2000 km, while 12 others rapidly moved a mean of 684 km (range 357–1298 km) away from drying inland sites to the coast. Two individuals moved longitudinally across the continent, departing and arriving at the same points, yet travelling very different routes; one bird moving more than 2200 km in less than 2.5 days, the other more than 1500 km in 6 days. Our findings reveal movements nearly twice as long and rapid as recorded in other desert waterbirds. We reveal capability to rapidly detect and exploit ephemeral wetland resource pulses across the stochastic Australian desert.

Context The study of threatened species is often challenged by their rarity and secretive life-history traits. Species adapted to extreme environments prone to stochastic conditions present further challenges because of fluctuating populations and patchy distributions. We employed a variety of methods to gather records and habitat information on the bronzeback legless lizard (Ophidiocephalus taeniatus), an endemic, nationally vulnerable monotypic pygopod reptile that is poorly understood because of fossorial, cryptic behaviour and remote distribution in the stony deserts of inland Australia. Aims Our aim was to determine foundational information on the distribution and landscape parameters relevant to this species and its disturbance-prone habitat and to formulate conceptual models to guide understanding, future research and management of threats. Methods We used multiple data sources, including targeted field surveys with Antakarintja traditional land owners across ~5000 km2 of previously unsurveyed habitat, sampled the catch of uncapped mine shafts with community volunteers, trialled artificial refuge substrates and elicited public opportunistic sightings. Key results We gathered 30 new records of the species from leaf litter mats of six shrub species, across four land systems. Examination of these records in the context of land system boundaries demonstrated a continuous distributional link between previously known areas of habitat and suggested large tracts of potential habitat that remain unsurveyed for the species. This information in combination with other published data was used to create conceptual models of habitat preference, population and disturbance, in which we suggest that O. taeniatus favours microhabitats that are prone to severe and long-lasting disturbance in some parts of the landscape, exacerbated by human land use practices. Conclusions Our study suggests that O. taeniatus distribution is unlikely to be severely fragmented, as had previously been suggested. Its total extent of occurrence may be greater than previously thought, despite a very low area of occupancy within this. Implications This study emphasises the value of using multiple, innovative data sources when studying rare and cryptic species. Further distributional surveys in identified areas of potential habitat in combination with testing and refinement of our conceptual model of habitat and population drivers are needed to fully assess the distribution, conservation status and ecological drivers of O. taeniatus.