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Sampling of environmental DNA (eDNA) and high‐throughput sequencing is emerging as an effective biodiversity assessment method in aquatic systems and may have utility for biodiversity inventory in terrestrial environments. Rock pools (gnammas) on granite inselbergs support a rich community of aquatic organisms and are culturally important to Indigenous peoples worldwide. However, the application of eDNA to survey rock pool biodiversity are undocumented. In a collaborative study with traditional owners, we explore the application of eDNA metabarcoding and traditional sampling methods to document and compare species richness and composition of eukaryotes from 15 rock pools (pits and pans) on granite inselbergs in southeastern Australia. We detected 116 taxonomic units, 81 assignments from eDNA sequencing and 35 species (23 rotifers and 12 microcrustaceans) using microscopic analysis. eDNA detected a broad range of taxa not previously documented from rock pools in Australia, although significantly more zooplankton (rotifers and microcrustaceans) were detected under a microscope, including several rare species and two undescribed species of rotifer. Brachionus calyciflorus and B. angularis were the only rotifer species assigned to species level through eDNA sequencing and were detected using both methods. We found no significant difference in mean species richness between rock pool types; however, species composition differed significantly between pits and pans. This study highlights the value of using eDNA to document biodiversity of ephemeral aquatic habitats in terrestrial ecosystems but reveals the general lack of reference sequence data for microorganisms, underscoring the value of using traditional sampling and taxonomic assignment methods. [ABSTRACT FROM AUTHOR]

Context: Fire regimes are changing with ongoing climate change, which is leading to an increase in fire frequency and severity. Australia's Black Summer wildfires burned >12 million hectares in 2019–2020, affecting numerous threatened animal species. One of the species predicted to be most impacted was the threatened southern greater glider, an arboreal, hollow-dependent folivore, endemic to eastern Australia's eucalypt forests. Aims: This study aimed to assess how the 2019–2020 wildfires affected greater glider abundance and the resources they depend on in Woomargama National Park, New South Wales, Australia. Methods: We categorised 32 sites into four fire severity treatments with eight sites for each treatment: unburned (continuous unburned vegetation); refuges (unburned patches within the fire's perimeter); low-moderate severity; and high severity. We carried out two spotlight surveys per site using the double-observer method, beginning 21 months after the fires. We also conducted vegetation assessments on the same transects. To analyse the data, we used Generalised Linear Models to compare habitat differences based on fire severity, and N-mixture models to model greater glider detectability and abundance in relation to habitat and fire severity. Key results: We found that fire severity depleted several habitat variables including canopy cover and the number of potentially hollow-bearing trees, a resource that greater gliders rely on. Greater glider abundance also decreased in all burn categories, with the greatest decline experienced in areas burned at high severity. We also found that greater glider abundance was much lower in fire refuges than unburned habitat outside of the fire zone. Conclusions: Greater glider declines following severe wildfire can be at least partly attributed to the level of vegetation loss and the associated loss of key habitat resources. The contribution of direct mortality to population declines remains unknown. Implications: Greater glider conservation will rely heavily on protecting expansive unburned areas of suitable habitat and maintaining hollow-bearing trees. This study aimed to assess the impact of the 2019–2020 wildfires on the abundance of the southern greater glider in Woomargama National Park, New South Wales, Australia. Our results indicated that southern greater glider populations were lower in areas that burned during the fires, as well as in small, unburned refuges. These declines were linked to the loss of critical resources, such as an intact canopy and hollow-bearing trees. Photograph by Mikayla Green. [ABSTRACT FROM AUTHOR]

Ecosystem engineers modify their environment and influence the availability of resources for other organisms. Burrowing species, a subset of allogenic engineers, are gaining recognition as ecological facilitators. Burrows created by these species provide habitat for a diverse array of other organisms. Following disturbances, burrows could also serve as ecological refuges, thereby enhancing ecological resistance to disturbance events. We explored the ecological role of Common Wombat (Vombatus ursinus) burrows using camera traps in forests of southeastern Australia. We compared animal activity at paired sites with and without burrows, from the same fire severity class and habitat. We examined how animal activity at Common Wombat burrows was affected by the 2019–20 Black Summer bushfires in Australia. We predicted that burrows would serve as hotspots for animal activity and as refuges in burned areas. The activity of several species including Bush Rat (Rattus fuscipes), Agile Antechinus (Antechinus agilis), Lace Monitor (Varanus varius), Painted Button-quail (Turnix varius), and Grey Shrike-thrush (Colluricincla harmonica) increased at sites where Common Wombat burrows were present, while other species avoided burrows. Species that were more active at burrows tended to be smaller mammal and bird species that are vulnerable to predation, whereas species that avoided burrows tended to be larger mammals that might compete with Common Wombat for resources. Species composition differed between sites with and without burrows, and burrow sites had higher native mammal species richness. The association of several species with burrows persisted or strengthened in areas that burned during the 2019–20 Black Summer bushfires, suggesting that Common Wombat burrows may act as ecological refuges for animals following severe wildfire. Our findings have relevance for understanding how animals survive, persist, and recover following extreme wildfire events. [ABSTRACT FROM AUTHOR]

Despite being a central aspect of a species' ecology and having important conservation implications, the use of fine‐scale habitat features (microhabitats), and how they vary over time, are poorly known for most species. In this study, we leveraged 522 relocations of radio‐tracked mallee tree dragons (Amphibolurus norrisi) and painted dragons (Ctenophorus pictus) to investigate the effect of environmental and individual variables on microhabitat use. Mallee tree dragons were more likely to use trees on hot days and in the middle of the day (the hottest time of day), whereas shrub use was more likely on cool days and in the mornings. Painted dragons were more likely to use shrubs and grass trees on warmer days and during the middle of the day, whereas burrows were used during cooler days and in the mornings and afternoons. We expect these patterns represent animals moving from refuge resources, occupied during unsuitable thermal conditions, to microhabitats offering basking, foraging and social opportunities during periods of thermal optimum. Additionally, we found evidence of an ontogenetic shift, with larger mallee tree dragons favouring tree use and higher perches, suggesting a transition from shrub to tree use with age. Our findings underscore the need for diverse microhabitats to accommodate the thermoregulatory and ontogenetic requirements of lizards. These insights can inform conservation and habitat restoration efforts, ensuring the provision of essential microhabitats to support species persistence. [ABSTRACT FROM AUTHOR]

Context: Freshwater ecosystems rank among the most threatened environments on Earth. Monitoring aquatic and semi-aquatic species is vital to informing conservation of freshwater ecosystems. However, many semi-aquatic mammals can be difficult to detect with conventional survey methods. Aims: We aimed to identify the most effective survey method for detecting an Australian semi-aquatic mammal, the rakali (Hydromys chrysogaster). Methods: We compared rakali detection rates among camera-trapping, live-trapping and visual surveys, and tested the influence of camera angle, trap proximity to water and time of survey, across the Yanco Creek system in southern New South Wales. Key results: Nocturnal spotlight surveys were the most effective method for detecting rakali, with most observations occurring while individuals were foraging or swimming in the water. Camera traps facing a floating platform and cage traps mounted on floating platforms performed better than those deployed on land. Downward-facing camera traps detected rakali three times more often than did forward-facing cameras. Trapping rakali was unreliable, with the species detected at fewer than half of the sites where presence was confirmed via visual observation and camera traps. For species absence to be determined with 95% confidence, 2–4 weeks of nightly trapping is required, compared with six nights of visual surveys or 12 nights for a platform-facing camera. Morning visual surveys were largely ineffective because of predominantly nocturnal rakali activity and difficulty in detecting signs in creek environments. Conclusions: The likelihood of detecting rakali can be maximised through the use of nightly spotlighting and deployment of baited camera traps focussed on platforms or natural resting areas within a water body. Implications: Understanding the effectiveness of each method is essential for developing species-appropriate protocols for population monitoring. Our findings present suitable options to be further explored among the 100-plus small (<1 kg) semi-aquatic mammals worldwide that share similar behaviours and characteristics to the rakali, many of which are threatened or data deficient. Cryptic semi-aquatic mammals present a particular challenge to monitor because of their unique lifestyles. We aimed to identify the most effective methods to detect the seldom-studied rakali, a native Australian semi-aquatic mammal; spotlighting and camera traps placed over water provided the greatest detection probabilities. We present a novel method to monitor rakali, which has the potential to improve the detection and conservation of other small semi-aquatic mammals. Photograph by Emmalie Sanders. [ABSTRACT FROM AUTHOR]

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Documenting the diet of organisms that have been introduced and naturalised outside their native range is a fundamental component of understanding their trophic interrelations in the receiving environment, and for developing holistic management practices for introduced species' predation impacts in an ecosystem. We describe two accounts of terrestrial reptiles in the diet of an introduced fish, rainbow trout Oncorhynchus mykiss in southern NSW, Australia. Our observations from the Southern Hemisphere together with recently published records from the Northern Hemisphere (e.g. USA, France and Italy) represent the presence of reptiles in the diet of O. mykiss across a broad geographical range and highlight a potential additional consideration of introduced salmonids and their impacts on terrestrial species. [ABSTRACT FROM AUTHOR]

Context. Water pumps fitted with filtering screens are effective for delivering water to floodplain environments and excluding large-bodied exotic fish; yet, the benefits to wetland fish and anurans are unknown. Aims. To quantify fish and tadpole responses to refilling wetlands with water pumps fitted with large-mesh screens following drawdown v. overland reconnections in themid-Murrumbidgee region of New South Wales. Methods. Frog and fish communities were compared between wetlands under managed inundation and overland reconnections by using PERMANOVA, and non-metric multidimensional scaling was used to evaluate community divergence between watering strategies. Classification and regression trees were used to identify thresholds in explanatory variables and predicted threshold responses in fish and tadpole abundance. Key results. Fish and tadpole communities differed in relation to watering strategies. Managed inundation resulted in a higher abundance of tadpole species and one native fish, whereas overland reconnections resulted in a high abundance of exotic fish species and fewer tadpoles. Water depth was a driver of tadpole abundance in two species, including the threatened southern bell frog (Litoria raniformis). Conclusions and implications. Using filtered pumps with large-mesh screens to deliver water to wetlands of high conservation value may be an effective strategy for reducing large-bodied exotic fish and enhancing frog and fish populations in regulated floodplain systems. [ABSTRACT FROM AUTHOR]

Restoring structural elements of habitats and understanding how restoration interacts with environmental factors such as grazing management can be crucial for improving conservation outcomes in agricultural landscapes. Surface rock is a structural habitat type that is critical for a range of reptile species; yet, it is often poorly managed and protected.Using a Before/After, Control/Impact (BACI) design, we experimentally quantified the response of reptiles to surface rock restoration in an agricultural landscape, and tested whether its effects interacted with livestock grazing treatments to influence various reptile diversity measures. To implement our crossed factorial design, we added approximately 50 tonnes of rock and 1 km of grazing exclusion fencing across 10 sites in south‐eastern Australia.We found increases in the number of total reptile captures, total individuals and species richness when comparing rock addition plots to non‐rock plots. There was no significant overall grazing exclusion effect or interactive effect of grazing and rock treatment on reptile measures.Synthesis and applications. Our study provides experimental evidence that surface rock addition is an effective restoration method for reptiles in agricultural landscapes. We recommend that the addition of surface rock is prioritised as a restoration tool for reptiles, and that existing surface rock areas are protected from clearing. [ABSTRACT FROM AUTHOR]

Context: Understanding what characteristics influence retreat-site selection by fauna is critical for both habitat management and species conservation. Despite the documented ecological values of surface rocks, there is limited knowledge of the attributes of surface rock that contribute to their use in agricultural landscapes or during winter months when reptiles are brumating, activity patterns are reduced, and sheltering individuals are most vulnerable to disturbance. Objectives: We surveyed reptiles sheltering beneath surface rocks in grazing farms in south-eastern Australia to address two questions: (i) What landscape factors influence the occurrence of reptiles over austral winter? (ii) What physical and thermal factors influence retreat-site selection? Methods: We surveyed 14 sites, with three plots per site, stratified across a gradient of canopy cover. We measured landscape attributes of surveyed sites and thermal and physical characteristics of individual surface rocks to quantify relationships between the occurrence of reptiles in the landscape and the properties of retreats selected. Results: We found that relatively small patches of surface rock can support high reptile numbers, with density estimates up to of 208 individuals per hectare. Reptile abundance was positively associated with increased elevation and limited canopy cover. Reptiles selected smaller rocks with high surface area to volume ratio, were minimally embedded in the soil, and rocks supporting few invertebrates. Conclusions: Conserving cryptozoic reptiles in agricultural landscapes can be enhanced through the appropriate management and retention of surface rock. We discuss implications for reptile conservation and surface rock management in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Arboreal lizards, especially species that inhabit flood-prone environments, have been poorly surveyed worldwide. We examined spatiotemporal patterns in arboreal lizard abundance and factors driving detection rates in floodplain environments using artificial bark covers, a non-destructive and cost-effective survey method. In total, 112 flexible, closed-cell foam bark covers were installed on eucalypt trees in 13 wetlands in the Murrumbidgee River floodplain of southern New South Wales, Australia, stratified by two inundation frequency treatments. Of four arboreal lizard species detected, the southern marbled gecko (Christinus marmoratus) (n = 41) and the tree dtella (Gehyra versicolor) (n = 8) were restricted to the mid-Murrumbidgee region, whereas the crevice skink (Egernia striolata) (n = 19) was restricted to the lower-Murrumbidgee region and did not co-occur with either gecko species. Mean detection rates of lizard species did not differ between frequently and infrequently inundated treatments but their abundance beneath covers varied significantly by month. For all detected lizard species, the presence/absence of the arachnid Holconia murrayensis represented a significant variable in explaining lizard occurrence patterns, particularly that of C. marmoratus. Artificial bark covers are a useful survey method for collecting distribution, abundance, and occupancy data on floodplain reptiles, although detection rates can be affected by the month, predator–prey interactions, and survey effort. Adopting passive, non-destructive reptile survey methods would greatly improve our knowledge of species' distributions and abundance patterns in vegetation communities subject to disturbance events. The distribution and abundance of wetland associated tree dwelling lizards has received little attention. Artificial bark covers (ABCs) were used as a survey method to investigate the distribution and abundance of known lizard species throughout the Murray–Darling Basin. ABCs were an efficacious survey method and have the potential for many avenues of research for floodplain associated lizards. Photo by Eva Moore. [ABSTRACT FROM AUTHOR]

Artificial refuges (cover boards) are commonly used to survey and monitor herpetofauna in many parts of the world. Despite the extensive use of artificial refuges in mesic environments, their effectiveness for detecting amphibians in temperate zones has rarely been examined. We compared amphibian detection probabilities between two survey methods; active searches of natural habitat and artificial refuges of three different types (corrugated steel, roofing tiles and timber railway sleepers). Our study area included five bioregions encompassing a 1180‐km latitudinal gradient across a modified, temperate eucalypt woodland vegetation community in south‐eastern Australia. We deployed 14 778 artificial refuges in terrestrial environments, within patches of remnant vegetation, and collected presence and abundance data on herpetofauna between 1999 and 2017. We used Bayesian logistic regression to identify the most effective survey method for detecting frog species across all bioregions. We modelled frog detections by fitting survey method, time since refuge deployment and rainfall prior to each survey. We detected 3970 individuals from 18 frog species. Overall, we found active searches and timber substrates most effective for detecting a broad range of species, although detection rates were driven by the numerically abundant spotted marsh frog Limnodynastes tasmaniensis. Timber refuges were effective for detecting several burrowing species, whereas active searches were effective at detecting habitat generalists. Quadratic effects of rainfall prior to survey as opposed to linear effects of time since artificial refuge placement was important in explaining frog detection rates in some bioregions. Active searches, timber railway sleepers and sheets of corrugated steel provide complimentary survey methods for detecting amphibians, although detection rates are influenced by rainfall patterns. Artificial refuges provide a time‐effective and standardized method for studying amphibians in their non‐breeding terrestrial environment and should be incorporated into future surveys and biodiversity monitoring programmes. [ABSTRACT FROM AUTHOR]

Preventing biodiversity loss in fragmented agricultural landscapes is a global problem. The persistence of biodiversity within remnant vegetation can be influenced by an animal's ability to move through the farmland matrix between habitat patches. Yet, many of the mechanisms driving species occurrence within these landscapes are poorly understood, particularly for reptiles.We used scented and unscented plasticine lizard models and wildlife cameras to (a) estimate predation risk of reptiles in four farmland types (crop field, pasture paddock, restoration tree planting and areas with applied woody mulch) relative to the patch edge and remnant vegetation, and (b) examine how predation risk was influenced by temporal change in the matrix (crop harvesting).Birds (55.1%), mammals (41.1%), reptiles (3.4%), and invertebrates (0.5%) attacked models, of which 87% were native species. Mammalian predators were 60.2% more likely to attack scented models then unscented models. Bird predators were not influenced by scent.We found predator attacks on models were highest at edges (49%, irrespective of adjacent farmland type, with a reduced risk within farmland (29%) and remnant patches (33%) (p < 0.01). Both mammal and bird predators contributed to high numbers of predation attempts at edges.Removal of crops did not increase predation attempts in crop fields or other farmland types, although predation attempts were significantly lower along the crop transect after harvesting, compared to the woody debris transect. However, numbers of predation attempts were higher in edge habitats, particularly prior to harvesting.Synthesis and applications. Reptiles are at risk of predation by birds and mammals in both remnant patches and the farmland matrix, particularly in edge habitat. Our results demonstrate that edge habitats are potentially riskier for lizards than the farmland. Vulnerability to predation may be increased by a lack of shelter within edge habitats such as by increasing visibility of reptiles to predators. Therefore, to benefit reptiles, land managers could provide shelter (rocks, logs, and grasses), particularly between remnants and linear plantings which could improve landscape connectivity. Reptiles are at risk of predation by birds and mammals in both remnant patches and the farmland matrix, particularly in edge habitat. Our results demonstrate that edge habitats are potentially riskier for lizards than the farmland. Vulnerability to predation may be increased by a lack of shelter within edge habitats such as by increasing visibility of reptiles to predators. Therefore, to benefit reptiles, land managers could provide shelter (rocks, logs, and grasses), particularly between remnants and linear plantings which could improve landscape connectivity. [ABSTRACT FROM AUTHOR]