The platypus (Ornithorhynchus anatinus) is a unique monotreme mammal from eastern Australia which can be difficult to study due to its semiaquatic lifestyle and nocturnal nature. Understanding which methods are most effective for studying this elusive species is key to optimising conservation actions. We compared the effectiveness of detecting platypuses using eDNA surveys with qPCR and metabarcoding analysis, camera trapping and visual stakeouts in waterways across the New England Tablelands and quantified activity patterns to optimise survey design. Out of ten survey sites, eDNA surveys with qPCR analysis, camera trapping and visual stakeouts were all effective, detecting platypuses at eight, seven and six sites, respectively. The least effective method was eDNA surveys using metabarcoding, which detected platypuses at only three sites. Camera traps showed platypuses were most active immediately after sunrise and just before sunset. For occupancy surveys, eDNA sampling using qPCR analysis is the most effective method; however, camera trapping and visual stakeouts were also useful, particularly in providing additional data on platypus behaviour.

Effective survey methods are critical to optimize conservation efforts for freshwater turtles. However, conventional trapping procedures often fail to detect or accurately represent juvenile cohorts. Combining trail cameras with basking platforms may provide a useful alternative method to sample juvenile turtles, but its efficacy remains unknown. Our study aimed to 1) quantify the effectiveness of basking platforms as a tool for surveying freshwater turtle populations and 2) determine whether the size structure of turtle samples differed between basking platforms and conventional trapping. Up to 18 basking platforms were deployed in 2022 and 2023 at six sites (3 platforms per site) in the New England Tablelands region of New South Wales, Australia, where Bell's turtle (Myuchelys bellii) and the eastern long-necked turtle (Chelodina longicollis) co-occur. Time-lapse trail cameras above the basking platforms documented turtle occurrences and body sizes, calculated from images using the software ImageJ. Both species basked on the platforms, taking 1-24 days to use the platforms and most commonly basked in late summer and early autumn. M. bellii was detected on platforms at four sites and C. longicollis at five sites. Platforms detected 1-20 M. bellii (x- = 2.33) and 1-10 C. longicollis basking events per day (x- = 3.01). Small turtles appeared in 26.4% of images of M. bellii and 23.5% of C. longicollis. A wider distribution of body sizes was recorded from basking platform images than from trapping data, including turtles less than 100-mm straight carapace length. Our results suggest that basking platforms are a valuable passive survey method for detecting freshwater turtles and juvenile cohorts in particular.

Where have all the baby turtles gone? Brooke loves watching the turtles in the creek on her farm. But in spring, she notices broken eggshells down near the water. What is happening to the turtle eggs? Brooke decides to use her detective skills and sets out to solve the mystery of the missing turtles! Reading level varies from child to child, but we recommend this book for ages 5 to 9.

Urban planning which enhances native biodiversity in and around cities is needed to address the impacts of urbanisation and conserve urban biodiversity. The “Biodiversity Sensitive Urban Design” (BSUD) framework incorporates ecological knowledge into urban planning to achieve positive biodiversity outcomes through improved urban design and infrastructure development. BSUD includes principles to direct strategic design and placement of connected wildlife habitat. However, effective BSUD implementation requires defining and quantifying the landscape-scale habitat connectivity needs of a range of taxon groups within urban contexts. The aim of our study was to use expert elicitation to address these gaps in landscape-scale habitat connectivity currently limiting the capacity of urban planning. We estimated habitat connectivity needs for seven representative taxon groups in urban environments, including ideal habitat, habitat constraints, barriers to movement, and movement thresholds that determine habitat connectivity. In using expert elicitation to quantify habitat connectivity requirements for urban biodiversity, our study provides insights on both the usefulness of expert elicitation to inform urban habitat connectivity planning generally, and the functional habitat connectivity requirements of our focal taxon groups specifically. Overall, we consider our expert-derived estimates of connected habitat to be a highly useful set of baseline data for habitat and connectivity modelling and urban planning for a range of taxon groups.

Turtles are among the world's most endangered vertebrates, with habitat destruction and predation as major contributors to population declines. Hatchling release programmes are increasingly implemented to enhance juvenile recruitment in threatened populations, but limited understanding of hatchling ecology impedes evidence-based management. To address this, we tracked western saw-shelled turtle (Myuchelys bellii) hatchlings using VHF micro-transmitters to quantify movement, habitat preferences, and survival during their first 2 weeks in the wild. We also compared soft-release and hard-release methods. Hatchlings moved an average of 47-62 m daily, dispersing both up- and downstream. Movement was influenced by water temperature and level, with higher water levels prompting increased downstream movements. The maximum cumulative distance moved by an individual hatchling was 2008 m over 13 days of tracking. Strong diurnal movement patterns were observed. Hatchlings predominantly used vegetation along the water's edge (99% of observations). They preferred shoals over steeply descending underwater banks and selected sedge-dominated areas more often than expected, avoiding phragmites-dominated areas, bare banks, and open water. Hatchling survival rates exceeded 90% during the tracking period. A comparison between soft- and hard-release methods revealed no advantage for soft-release animals. Our findings suggest that releasing M. bellii hatchlings into preferred microhabitats could enhance conservation outcomes. Furthermore, we highlight the crucial role of vegetative cover along stream edges in providing shelter for hatchlings.

Freshwater turtles in the Murray-Darling Basin (MDB), Australia, have declined since the 1970s. Intense nest predation by introduced foxes likely contributes to these declines, disrupting juvenile recruitment needed to sustain populations. Traditional lethal control methods, such as baiting and shooting, have proven inadequate, highlighting the need for innovative conservation strategies. We tested three nest protection methods-fenced nesting beaches, artificial floating islands (artificial nesting habitat), and individual mesh covers-for reducing fox predation. Using artificial turtle nests across protected and unprotected plots, we monitored nest predation with remote cameras and confirmed nest status through excavation. On average, nest predation was lowest on artificial islands (17%), followed by fences (37%) and mesh (40%). All protection methods significantly reduced depredation compared to unprotected controls (85% destroyed). Unprotected nests were almost exclusively depredated by foxes, while protected nests saw more predation from native animals. Native predator species did not differ among protection treatments. Our findings underscore the potential for artificial floating islands as a valuable conservation tool. Further research into optimizing nest protection and understanding ecological impacts is critical for improving recruitment and reversing declines of freshwater turtle species.

Turtles are among the most imperilled vertebrate groups, with over 50% of the world's turtle species at risk of extinction due to a range of environmental and anthropogenic challenges. Despite the apparent persistence of many turtle species owing to their long adult lifespans, high early-life mortality can contribute to population declines by disrupting juvenile recruitment and preventing the replacement of aging adults. For long-lived species that are already slow to recover from declines, reduced recruitment can further delay population recovery, underscoring the need for continued research in this area. Preventing further turtle extinctions requires targeted conservation across all life stages, yet efforts are hindered by gaps in understanding the drivers of recruitment failure and the most effective management strategies. Common threats to recruitment include predation and climate change pressures; however, less-frequently cited factors, such as environmental contamination and food availability, may also play significant roles. For recruitment-enhancing strategies like nest protection, habitat restoration, and predator management to be effective, they must be tailored to the most pressing threats facing the managed turtle population and designed to align with available resources. Strategies should be both feasible to implement and scaled appropriately to match the severity and extent of the threats they aim to address. Integrating targeted interventions to mitigate recruitment loss with broader conservation efforts - such as improving food availability and reducing human impacts - is critical for reversing population declines and ensuring long-term species persistence. Here, we synthesise current knowledge on the barriers to juvenile recruitment, evaluate the efficacy and limitations of existing conservation measures, and identify critical priorities for future research and management.

Climate change and human activity are changing the characteristics of freshwater systems all over the world. Water quality is an important environmental variable to turtles, and many species have limited tolerances to different abiotic parameters. Despite the potential for extreme effects of water quality variables on turtle physiology and behaviour, we still do not understand the extent to which many species identify and select different water quality parameters within their habitats. The eastern long-necked turtle (Chelodina longicollis) resides in both natural and highly degraded systems throughout south-eastern Australia. However, their ability to perceive the quality of these environments and whether they select a habitat based on specific water quality attributes is unknown. Our objective was to identify the preferences of eastern long-necked turtles to different water quality parameters. We quantified the time spent in varying concentrations of five abiotic variables: dissolved oxygen, fertiliser, pH, salinity, and turbidity. Testing arenas consisted of four tubs, each with a different concentration of a selected water quality variable, and turtles were allowed to choose in which concentration they spent their time. This was replicated for each of the five variables, using a sample size of 10 turtles. Eastern long-necked turtles strongly preferred the freshwater control treatment over treatments with high salinity. They did not show strong preferences towards treatments with different dissolved oxygen, turbidity, and fertiliser or pH. We show that although C. longicollis occupies a variety of natural and man-made water bodies, they do prefer specific salt concentrations, which may influence their subsequent habitat selection within their range. Our trial model may also reveal stronger habitat preferences of more sensitive turtle species, which may be increasingly vulnerable to changes in their natural habitats.

Turtles are declining globally, and absences of juveniles during surveys are often interpreted as evidence of threats to early life stages. In Australia, for example, it is widely argued that a low number of juveniles is likely due to nest predation by introduced red foxes ( Vulpes vulpes ). However, small sample sizes within populations, low detectability of juveniles and turtles' long lifespans often confound the conclusion that a paucity of juveniles indicates a declining population. Because turtles have long reproductive lifespans, we might intuitively expect most turtle populations to be heavily weighted towards large individuals, but a ‘typical’ or ‘healthy’ size distribution for turtle populations has not been well established. Therefore, we collated data on 41,021 freshwater turtles from 38 species and 428 populations located in parts of Australia both with and without introduced foxes, as well as populations in the United States of America, which naturally have raccoons ( Procyon lotor ), foxes and other nest predators. We examined population‐level body size distributions to establish a baseline for ‘typical’ turtle populations and test whether populations that are exposed to introduced foxes have proportionately fewer juveniles compared to both AU populations that lack introduced foxes and USA populations that are naturally exposed to nest predators. We found that most turtle populations in AU and the United States were heavily skewed towards adults and had few juveniles, regardless of the presence of foxes or other nest predators. There were, however, clear differences among population survey methods: those that target shallow areas (e.g. crawfish traps) tended to capture proportionately more juveniles, and small sample sizes (∼<50) often produced inaccurate representations of size distributions. Additionally, we used a simulation to demonstrate that, given common turtle life history parameters, even stable populations should generally have low proportions of juveniles. Based on our results, we encourage caution when interpreting turtle size distributions. A small number of juveniles does not inherently suggest that a population is declining due to high egg and/or juvenile mortality, and researchers should pay careful attention to the biases in their methods and strive to capture a minimum of 50–100 turtles before drawing inferences.

Previous articleNext article No AccessZoologySo Many Snakes, So Little Time: Uncovering the Secret Lives of Australia's Serpents. By Rick Shine. Boca Raton (Florida): CRC Press (Taylor & Francis Group). $79.96 (hardcover); $31.96 (paper). ix + 282 p.; ill.; index. ISBN: 9781032234618 (hc); 9781032232928 (pb); 9781003277712 (eb). 2022.Deborah S. BowerDeborah S. BowerEarth & Environmental Science, University of New England, Armidale, New South Wales, Australia Search for more articles by this author PDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmailPrint SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 99, Number 2June 2024 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/730663 PermissionsRequest permissions For permission to reuse, please contact [email protected].PDF download Crossref reports no articles citing this article.

Context. The increasing number and length of droughts is a threat for many freshwater turtle populations. Aims. Our study investigated the movement and survival of Emydura macquarii, Chelodina expansa and Chelodina longicollis in drought and flood conditions. Methods. Turtles were captured in the Gwydir Wetland, New South Wales, Australia. We assessed the species composition of live captures and carcasses over the drought to assess relative survival among species. Using radiotelemetry, we compared the movement of E. macquarii and C. longicollis over a severe drought followed by a flood. Key results. For tracked turtles with known fates, 28.6% of E. macquarii and 7.1% of C. longicollis, died during the drought. The proportional composition of captured turtles compared with those of desiccated shells suggested that C. expansa had the highest mortality. E. macquarii and C. longicollis both appeared to navigate terrestrially and moved further in the flood water than in the drought, but C. longicollis moved further generally. Conclusions. Our findings suggest that turtles in isolated wetlands of the northern Murray-Darling Basin are at high risk of mortality during severe drought. Implications. Environmental water delivery during periods of sustained drought will be critical to ensure persistence of populations of long-lived species such as turtles.

Fences disturb the movements of terrestrial species, altering migration patterns, limiting access to vital resources, and reducing genetic diversity. With almost 40% of the Earth's land surface converted for agriculture, farm fencing to protect crops and corral livestock is expected to stretch into the millions of kilometers. As semi-terrestrial ectotherms, freshwater turtles are threatened by fences that limit access to resources and increase risks of desiccation, entanglement, and overheating, often resulting in death. To determine the effect of fences, we quantified the movement patterns for a population of eastern long-necked turtles (Chelodina longicollis) inhabiting an agricultural landscape near Armidale, New South Wales, Australia from November 2022 to September 2023. There was considerable variation in the distance traveled, home range size, and movement corridor selection between turtles that was not explained by the morphological factors of size, mass, or the loss of a limb (likely due to predation attempts). On average, 38% +/- 4.70 (x +/- SE) of turtle movements were terrestrial (overland) during their active season (spring and summer) during which they encountered fences frequently because of a complex matrix of paddocks. Fence design dictated the distance turtles traveled to locate a suitable passage point. The majority of fences allowed turtles to pass (turtle-friendly fences, 71.4% of total fence distance) as opposed to turtle-unfriendly fences (28.6% of total fence distance). Turtles were required to travel almost 4 times the distance to locate a suitable crossing point (a gap or fault in the fence) when they encountered an unfriendly fence (85.32 m +/- 29.81) compared to a turtle-friendly fence (25.85 m +/- 3.58). Our results highlight the need for land managers to avoid small-diameter exclusion fencing and fence designs containing chicken wire that extend to or below ground level. In settings where small-diameter wire fencing is required, we recommend the installation of turtle gates for small terrestrial fauna or elevating bottom wires at least 50 mm above ground level to facilitate fence permeability.

Frozen water bodies provide a physiological challenge to fauna by physically limiting access to atmospheric oxygen. To tolerate low temperatures, reptiles use brumation as a physiological strategy in winter. Cryptodira vary in their tolerance to freezing conditions but the extent of tolerance in pleurodirans is largely unknown. Australia's freshwater turtles inhabit warmer regions with less severe winters and have well-developed mechanisms to cope with high temperatures and drying waterbodies, rather than extreme cold tolerance. Chelodina longicollis is a widespread Australian freshwater turtle species that tolerates high temperatures and desiccation during hot, dry periods while also undergoing brumation during winter months. Despite extensive research, limited observations exist on their behaviour during severe winter periods at the extremes of their range. In an 11-month tracking study, we monitored adult C. longicollis, noting their movements, locations, and temperature weekly. We observed an adult female C. longicollis which, during a seven-month period within a single creek pool, survived brumation in extreme cold water including a 15-day period of total freezing of the surface water. After the ice melted following a rain event, the turtle was recaptured alive. This marks the first observation of brumation for an Australian chelid species under ice.

Genetic mutations resulting in abnormal colouration occur across all vertebrate groups but are considered rare, especially in mammals. Hypo-pigmentary conditions can be separated into albinism, leucism and piebaldism. The impact of colour variation on an animal’s risk of predation and its ability to blend with its surroundings is widely recognised. We report our observations of a white platypus (Ornithorhynchus anatinus) in a tributary of the Gwydir River in the upper reaches of the Murray Darling Basin, New South Wales, Australia. We describe our observations in the context of historical platypus records since 1835.

Abstract Anthropogenic landscape change due to urbanisation, agriculture and resource extraction inevitably results in linear barriers within the landscape. Artificial linear structures such as roads, fences, levees, and dams limit the movement of some species and further fragment residual habitat. In this study, we investigated the ability of Eastern long-necked turtles (Chelodina longicollis) to cross various terrestrial obstacles commonly encountered in their habitat. We tested two types of fences (chicken wire and exclusion fencing) commonly used in agricultural systems and three sizes of rocks (gravel, gabion, and large boulders) often used for road construction, erosion control, and waterway stabilisation. We examined the success rates of turtles in crossing obstacles, the effect of fatigue on crossing attempts, and the impact of individual boldness on movement behaviour. Turtles displayed high success rates in crossing gravel (85.4%), gabion (86%), boulders (73.3%) and hinged joint exclusion fencing (94.7%). Chicken wire style wire netting had no successful crossings (0%) despite 276 attempts. A significant fatigue effect was observed throughout the experiment, with turtles making an average of 3.94 (± 4.93 SE) fewer attempts at the end of the experiment (day eighteen) as opposed to day one. Bolder turtles were faster at crossing obstacles, however, boldness had no bearing on obstacle-crossing success. These results highlight the need for thoughtful selection of waterway and wetland infrastructure and the fatiguing impact of constant exposure to anthropogenic barriers for wildlife.

ABSTRACT Australian freshwater turtle populations have declined substantially, with consequent losses to aquatic ecosystem functions. A leading hypothesis is that turtles have declined through lost recruitment caused by high nest predation by invasive foxes. The ‘fox hypothesis’ is supported by experiments showing that nest predation rates exceed 95% in many regions. Furthermore, population surveys have repeatedly found absences of juvenile turtles, and headstarting experiments have successfully replaced those juveniles in some species. We are currently leading a nationwide citizen science program, ‘1 Million Turtles’ (1millionturtles.com), to engage local communities to protect turtles from threats like nest predation using a suite of novel approaches. Our key innovation is to leverage community passion and interest for turtles to create positive conservation impacts via a nationwide support network. We provide a data collection tool and framework (TurtleSAT) and self-guided training in conservation methods. We assist with guidance for gaining licencing and permission, and applying for grants. We are evaluating our approach through both the impacts on turtle populations as well as through surveys of our engaged citizen scientists. Ultimately, we aim to create a science-supported, national grassroots conservation model where community champions can lead their own evidence-based approaches to help wildlife.

Australia's freshwater turtles have high endemicity and many are threatened by extinction. Following a symposium held at the 2022 conference of the Australian Society of Herpetologists, we summarized the current status of research and conservation for Australian freshwater turtles and identified opportunities for future research. Eight species (32%) of Australia's 25 native freshwater turtles are listed as threatened by Australia's Federal Government. Symposium discussions on the primary gaps in research identified the lack of baseline data to inform population modelling as a key deficiency. Knowledge of the most effective conservation actions, the effectiveness of attempts to aid population recovery, and whether these actions are required at all, remains lacking for many species. A heavy bias exists between some well-studied species compared with others for which little or no information is published. Community science, engagement with First Nations people, advances in technology, and recognition of the importance of turtles are contributing to better knowledge.

Introduced red foxes (Vulpes vulpes) are a major predator of freshwater turtle nests in Australia. We evaluated the effectiveness of electric fences, in combination with individual nest protection, for shielding western saw-shelled turtle (Myuchelys bellii: Chelidae) nests from predation by foxes. We compared the numbers of raided and intact turtle nests found in paired fenced treatment and unfenced control areas of streambank. We also individually protected all intact nests found in both area types with wire mesh or a steel cage. The total numbers of nests found in treatment and control areas did not significantly differ from parity, but significantly more intact nests were found in treatment areas and significantly more raided nests in control areas. The fences were occasionally damaged by livestock, wildlife and flooding, rendering them inoperative for varying periods of time until repair. However, foxes raided nests inside the fences on only two occasions, despite these breaks in functionality. Our study demonstrates that electric fences can provide an effective method of protecting entire nesting areas from depredation by foxes.

Catastrophic megafires can increase extinction risks; identifying species priorities for management and policy support is critical for preparing and responding to future fires. However, empirical data on population loss and recovery post-fire, especially megafire, are limited and taxonomically biased. These gaps could be bridged if species' morphological, behavioural, ecological and life history traits indicated their fire responses. Using expert elicitation that estimated population changes following the 2019-20 Australian megafires for 142 terrestrial and aquatic animal species (from every vertebrate class, one invertebrate group), we examined whether expert es-timates of fire-related mortality, mortality in the year post-fire, and recovery trajectories over 10 years/three generations post-fire, were related to species traits. Expert estimates for fire-related mortality were lower for species that could potentially flee or shelter from fire, and that associated with fire-prone habitats. Post-fire mortality estimates were linked to diet, diet specialisation, home range size, and susceptibility to introduced herbivores that damage or compete for resources. Longer-term population recovery estimates were linked to diet/habitat specialisation, susceptibility to introduced species; species with slower life histories and shorter subadult dispersal distances also had lower recovery estimates. Across animal groups, experts estimated that recovery was poorest for species with pre-fire population decline and more threatened conservation status. Sustained management is likely needed to recover species with habitat and diet specialisations, slower life histories, pre-existing declines and threatened conservation statuses. This study shows that traits could help inform management priorities before and after future megafires, but further empirical data on animal fire response is essential.

Cooper Creek is one of Australia's largest unregulated river systems and one of the world's most variable large river systems. It is a dynamic environment that oscillates between booms and busts; yet, many species thrive in it. One of these species, the Cooper Creek turtle (Emydura macquarii emmotti) has received little attention, despite being one of Australia's largest freshwater turtles and living further inland than any other Australian turtle. We conducted surveys for E. m. emmotti in 2001-2004, 2019, and 2022, focussing predominantly on the Waterloo waterhole. Waterloo had a large population of E. m. emmotti (508 estimated individuals; 95% CI = 447-596) with an estimated density of 64.8 turtles/ha (95% CI = 57.0-76.2) and estimate biomass of 74.4 kg/ha (95% CI = 57.6-100.3 kg/ha). Juveniles were highly abundant in all years, representing up to 63.6% of captured individuals. It was slightly (but not significantly) male-biased in 2001-2004 and significantly female-biased in 2019. All sizes and sexes used the floodplain during a flooding event in 2022, but more males than females were captured on the floodplain, and there was evidence of male-biased dispersal across the years. Compared to Murray River turtles (Emydura macquarii macquarii), E. m. emmotti exhibited megacephaly across all ages and sexes, with particularly pronounced megacephaly in adult females. Algae were present on many individuals (including on the skin and plastron) but was relatively more abundant on juveniles. Leeches were not detected on any of the 66 turtles that were examined for them. The following injuries/malformations were noted: missing or injured limbs (3.2%), missing or injured eyes (1.3%), damaged shells (8.0%), scute/shell anomalies and malformations (10.6%), and marginal scute seams extending into the costals (67.4% of adults, 1.2% of juveniles). This paper presents some of the first work on this unusual turtle and makes recommendations for future research.