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Anthropogenic landscape change due to urbanization, agriculture, and resource extraction results in barriers within the landscape. Artificial 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 throughout their habitat. We tested two types of fences (chicken wire and hinged joint exclusion fencing) commonly used in agricultural systems and three sizes of rocks (gravel, cobbles, and boulders) often used for road construction, erosion control, and waterway stabilization. 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 had high success rates in crossing gravel (85.4%), cobbles (86%), boulders (73.3%) and hinged joint exclusion fencing (94.7%). Turtles did not successfully cross chicken wire fencing (0%) despite 276 attempts. A significant fatigue effect occurred throughout the experiment, with turtles making an average of 3.94 (±1.42 SE) fewer attempts at the end of the experiment (day 18) than on day 1. Bolder turtles were faster at crossing obstacles, but boldness had no influence on obstacle‐crossing success. Our results highlight the need for thoughtful selection of waterway, wetland, and riparian bordering infrastructure and the fatiguing impact of constant exposure to anthropogenic barriers for wildlife. [ABSTRACT FROM AUTHOR]

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¯ $\bar{x}$ ± 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. This study investigated the survival and movement of Emydura macquarii , Chelodina longicollis and Chelodina expansa in the Gwydir Wetlands of New South Wales. E. macquarii and C. longicollis were tracked using radiotelemetry and our findings suggest that they navigate terrestrially. Freshwater turtles isolated in drier regions of the Murray–Darling Basin are at high risk of mortality in severe drought. This article belongs to the collection Environmental Flows in Northern Murray–Darling Basin: what we know about the science and management after a decade of practice. [ABSTRACT FROM AUTHOR]

Many freshwater turtle species have spread beyond their natural distributions through human agency, but introduced populations can be difficult to differentiate from natural ones. The occurrence of an Australian freshwater turtle, Emydura macquarii, in the Greater Sydney region, Australia's most populous urban and peri-urban area, has alternatively been assumed to be natural or deduced to be due to anthropogenic introduction. I apply multiple lines of evidence to show that the occurrence of E. macquarii in the Sydney region is not natural and that the species has proliferated and spread there much more than the notoriously invasive red-eared slider turtle, Trachemys scripta elegans. The E. macquarii population of the Sydney region is highly diverse morphologically, with individuals variously resembling E. macquarii from Queensland, the north coast of New South Wales, and the Murray–Darling Basin. Better understanding is needed of the population genetics of E. macquarii in the Sydney region, the interactions among the region's native and introduced turtles, and the impacts of E. macquarii on biota other than turtles. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to explore the effect point of capture has on relative weight (Wr), as well as haematology and biochemistry values, in wild eastern longneck turtles (Chelodina longicollis). This study group consisted of two sites of turtles residing in Duck Pond (DP) and Ivanhoe Wetland (IW) in the Darebin Parklands, in Alphington, Melbourne. From DP, 184 turtles were captured, and from IW, 37 turtles were captured. All turtles were weighed and measured, and a random subset of 20 turtles from each waterbody was selected for blood collection. Significant differences were found to exist for Wr, basophils, glucose, uric acid, triglycerides and bile acids between the two sites. Serum glucose levels tended to decrease as a turtle increased in mass, straight carapace length (SCL) and Wr. The results of this investigation highlight the need to take location into consideration when assessing blood parameters in reptiles. Reptile physiology is heavily influenced by a range of external factors, one of which is environment. In this investigation it was shown that turtles originating from two different ponds, separated by only 200 m, had significantly different blood parameters and body conditions. This research highlights the need to consider location when assessing health and physiology in reptile species. Photograph by Titus Franciscus Scheelings. [ABSTRACT FROM AUTHOR]

Constructed wetlands may compensate to some degree for the impact of the loss of natural wetlands on aquatic biodiversity. However, information is lacking on the relative value of artificial wetlands and comparable natural wetlands for freshwater turtles. I contrasted the population structure, diet and body growth of Australian eastern long-necked turtles (Chelodina longicollis) in artificial and natural ponds in farmland settings. Turtle populations in the artificial ponds had a more even distribution of body size, and a much larger proportion of young individuals, than those in the natural ponds, suggesting that the artificial ponds were important recruitment sites. Diet differed little between the two types of ponds, being greatly dominated by aquatic insects in both cases. However, body growth of juvenile turtles was on average more rapid in the artificial ponds, possibly because they were generally permanent, unlike the natural ponds. These findings suggest that artificial farm ponds are valuable habitats for C. longicollis, which may foster population recruitment that counters the effects of introduced nest predators and road mortality. [ABSTRACT FROM AUTHOR]

Background: Mycobacterial infections are uncommonly diagnosed in reptiles. These infections are often systemic, chronic, and well advanced before presentation and diagnosis. Turtles, both marine and freshwater, appear to have a higher prevalence of the disease than other reptiles, perhaps because of their aquatic environment. Case report: An Eastern Long‐neck turtle (Chelodina longicollis) was diagnosed with an apparently localised mycobacterial infection in the right foot. Biopsy, culture and PCR were used to make the diagnosis. Treatment with clarithromycin and rifampicin given orally for 9 months appeared to successfully resolve the infection. Conclusion: Antemortem diagnosis is difficult although molecular diagnostic techniques are improving the rates of diagnosis. Treatment of mycobacteria is lengthy, difficult and challenging to the patient, the owner and the veterinarian. For this reason, and because of the potential for zoonotic infection, it is infrequently undertaken. [ABSTRACT FROM AUTHOR]

The pharmacokinetics of fluoroquinolones in chelonians are well described but this does not extend to pradofloxacin, a broad‐spectrum veterinary fluoroquinolone available as an oral suspension for cats and dogs. The aim of this study was to investigate the single‐dose pharmacokinetic profile of pradofloxacin oral suspension at 7.5 mg/kg in eastern long‐necked turtles (Chelodina longicollis). Eight treated turtles were sampled at multiple time points up to 168 hr. Plasma concentrations were measured using high‐performance liquid chromatography. Pradofloxacin was quantifiable for up to 48 hr after drug administration. The Tmax (9.0 hr) and T½ to 48 hr (13.16 hr) were longer, and the Cmax (0.2 μg/ml) and AUC0‐24 (2.2 hr*μg/ml) lower, than previously reported in cats and dogs. Pradofloxacin was measurable in tank water samples for up to 48 hr. No adverse effects were observed in six turtles administered 7.5 mg/kg sid for 7 days. Using mammalian MIC data, the AUC0‐24/MIC ratios for a range of bacterial isolates suggest that this dose of pradofloxacin in turtles is unlikely to be effective against many bacterial pathogens. [ABSTRACT FROM AUTHOR]

The abilities of freshwater turtles to control their body temperatures by behavioural means have implications for activity, food ingestion and digestion, growth, reproduction and potential responses to climate change. I compared various forms of basking in nature, and responses to aquatic and aerial photothermal gradients in the laboratory, among three species of Australian chelid turtles: Chelodina expansa , C. longicollis and Emydura macquarii. Proclivity for behavioural thermoregulation varied substantially among these species, being highest in C. longicollis and lowest in C. expansa. However, C. expansa had a thermophilic response to feeding. For C. longicollis and E. macquarii , behavioural thermoregulation may enhance colonisation of more southerly latitudes or higher elevations as climatic warming proceeds. However, increasing air temperatures may pose a hazard to turtles dispersing or sheltering terrestrially (for example, when water bodies dry during drought). C. longicollis appears the best placed of the three species to avoid this hazard through its abilities to thermoregulate behaviourally and to aestivate in terrestrial microenvironments that are buffered against temperature extremes. How behaviour affects a turtle's body temperature has implications for its feeding, growth, reproduction and likely responses to climate change. I found that three Australian freshwater species differed in their tendency to regulate body temperature, both in nature and in the laboratory. The eastern long-necked turtle had the greatest such tendency, which may help to protect it from overheating and dehydration when on land. Photo by Bruce C. Chessman. [ABSTRACT FROM AUTHOR]

Oxygen consumption (ZO18062_E1a.gif) of Chelodina expansa , C. longicollis and Emydura macquarii (Pleurodira: Chelidae) was measured at rest and during induced exercise at 8, 13, 18, 22, 26, 30 and 34°C. Resting ZO18062_E1a.gif varied significantly among species, being lowest in C. expansa , which is the most sedentary of the three species in nature, and highest in E. macquarii , which is the most energetic, but active ZO18062_E1a.gif did not differ significantly among the three species overall. For both Chelodina species, resting ZO18062_E1a.gif was appreciably lower than expected from regression of ZO18062_E1a.gif on body mass for non-marine turtles globally, a result that reinforces previous evidence of low resting metabolism in Australian chelid turtles. Active ZO18062_E1a.gif of all three species at higher temperatures was similar to ZO18062_E1a.gif reported for active freshwater cryptodires. Resting ZO18062_E1a.gif of all three species increased similarly with temperature, but active ZO18062_E1a.gif and aerobic scope did not. In C. expansa and E. macquarii , active ZO18062_E1a.gif and aerobic scope increased over the full temperature range assessed but in C. longicollis these variables reached a plateau above 22°C. Projected increases in freshwater temperatures in south-eastern Australia as a result of global warming are likely to enhance activity, feeding and growth of the three species (subject to food availability), especially in cooler seasons for C. longicollis and warmer seasons for C. expansa and E. macquarii. However, other aspects of predicted climate change, especially increased drought, are likely to be detrimental. Projected climate change will affect aspects of animal physiology such as oxygen requirements. Oxygen consumption at rest and during activity in three species of freshwater turtles was compared, and differences among the species in average consumption rates and in responses to temperature variation were found. These results predict that the species respond to climate change in different ways. Photo by Bruce Chessman. [ABSTRACT FROM AUTHOR]

Freshwater turtle populations are globally threatened by many factors. Complicating matters, their longevity requires long-term monitoring on the scale of decades to assess changes in population size, yet few long-term studies exist. Documenting population estimates and trends is essential for identifying and conserving imperilled populations, however, the impacts of many current threats may render populations endangered well before declines become apparent. By that stage, population recovery may not be possible, thus assessing population level impacts of potential threats may provide a direct measure of risks of population extinction. Australian turtles face major threats of mortality from invasive species, vehicles, disease and declining water quality. Even Australia's most abundant and widespread species has declined by up to 91% in some populations. Here I use population models to assess the impacts of threats to multiple life history stages of an Australia turtle. This study clearly demonstrates that Chelodina longicollis , Australia's most widespread turtle (1) is resilient to high levels of nest predation for sustained periods, (2) requires only periodic levels of reduced nest predation and pulse recruitment to maintain population viability and (3) low levels of adult mortality can drive populations to extinction. Turtle populations require pulse recruitment (i.e. nest predation rates declining to <35% every ten years) and monitoring of nest predation rates for 5–6 years to determine whether nest predation level profiles are extreme. However, if terrestrial mortality of adult turtles occurs, then the risk of extinction is high regardless of nest predation levels. Monitoring protocols to assess nest predation and adult mortality rates are not widely developed for freshwater turtles and here I develop a management plan that employs Citizen Science and standardised on-ground protocols to assess levels of threats at the population level. Standardised protocols and involvement of the public and community groups creates a network for broad-scale assessment and management of a species. Although threats can be identified and easily quantified and long-term data has demonstrated the extent of the decline of freshwater turtle populations in southern Australia, solutions to minimise risks of extinction need to be developed and fast-tracked before turtles throughout Australia become critically endangered. [ABSTRACT FROM AUTHOR]

For several decades there has been recognition that water resource development alters river flow regimes and impacts ecosystem values. Determining strategies to protect or restore flow regimes to achieve ecological outcomes is a focus of water policy and legislation in many parts of the world. However, consideration of existing environmental flow assessment approaches for application in Queensland identified deficiencies precluding their adoption. Firstly, in managing flows and using ecosystem condition as an indicator of effectiveness, many approaches ignore the fact that river ecosystems are subjected to threatening processes other than flow regime alteration. Secondly, many focus on providing flows for responses without considering how often they are necessary to sustain ecological values in the long-term. Finally, few consider requirements at spatial-scales relevant to the desired outcomes, with frequent focus on individual places rather than the regions supporting sustainability. Consequently, we developed a risk-based ecohydrological approach that identifies ecosystem values linked to desired ecological outcomes, is sensitive to flow alteration and uses indicators of broader ecosystem requirements. Monitoring and research is undertaken to quantify flow-dependencies and ecological modelling is used to quantify flow-related ecological responses over an historical flow period. The relative risk from different flow management scenarios can be evaluated at relevant spatial-scales. This overcomes the deficiencies identified above and provides a robust and useful foundation upon which to build the information needed to support water planning decisions. Application of the risk assessment approach is illustrated here by two case studies. [ABSTRACT FROM AUTHOR]

Knowledge of growth rates and maturation times of freshwater turtles is important in assessing population viability. I analysed growth of Australian eastern long-necked turtles (Chelodina longicollis) from individual capture–recapture records spanning periods of up to 17 years for a population in Gippsland, Victoria, close to the high-latitude end of the species' natural range. Juvenile growth was rapid and similar among individuals but adult growth was usually slow, highly variable among individuals and erratic within individuals over time. In addition, asymptotic body lengths were disparate among individuals for both males and females. Von Bertalanffy growth models fitted separately to males plus unsexed juveniles and females plus unsexed juveniles performed better than logistic models but tended to underestimate growth rates for very small and very large turtles and overestimate growth for medium-sized individuals. Sexual maturity was estimated to be achieved at 10 years in males and 16 years in females, which is late compared with most estimates for other populations of C. longicollis and for other turtle species in south-eastern Australia. The high variability of individual growth in this population makes age estimation from body size unreliable beyond the first few years of life. For southern Chelodina longicollis , juvenile growth is rapid and similar among individuals, but adult growth is usually slow, erratic over time and varied among individuals. Asymptotic body length is variable for both sexes. Growth models suggest that sexual maturity occurs at 10 years in males and 16 years in females. Photo by Bruce Chessman. [ABSTRACT FROM AUTHOR]

Hatchlings of several species of freshwater turtles have been reported to remain in subterranean nests for extended periods following hatching from the egg. It has been suggested that this delayed emergence, including overwintering in the nest in populations at temperate latitudes, is an evolved adaptation that enables hatchlings to enter the aquatic environment at the most propitious time for survival and growth. I monitored nests of a temperate-zone population of the freshwater Australian eastern long-necked turtle (Chelodina longicollis) for up to a year after nest construction in fine-grained soils adjacent to oxbow lakes and farm ponds. An estimated 84% of nests were preyed on, probably mainly by non-native red foxes (Vulpes vulpes), whereas hatchlings emerged from autumn to spring from an estimated 5% of nests. The remaining 11% of nests were neither preyed on nor had emergence by a year after nest construction. Live hatchlings were present in some nests with no emergence up to 10 months after nest construction, but substantial numbers of dead hatchlings were present beyond nine months. It therefore seems unlikely that emergence occurs more than a year after nest construction. Delayed emergence of this species in this environment appears less likely to be an adaptive strategy than to be a consequence of imprisonment in the nest by hard soil that is difficult for hatchlings to excavate. Delayed nest emergence of freshwater turtle hatchlings is considered an adaptation whereby hatchlings enter the aquatic environment at the best time for survival and growth. However, delayed emergence in a population of the Australian turtle, Chelodina longicollis , appeared to be mainly due to imprisonment in the nest by hard soil. Photo by Bruce Chessman. [ABSTRACT FROM AUTHOR]

Ex situ conservation tools, such as captive breeding for reintroduction, are considered a last resort to recover threatened or endangered species, but they may also help reduce anthropogenic threats where it is difficult or impossible to address them directly. Headstarting, or captive rearing of eggs or neonate animals for subsequent release into the wild, is controversial because it treats only a symptom of a larger conservation problem; however, it may provide a mechanism to address multiple threats, particularly near population centers. We conducted a population viability analysis of Australia's most widespread freshwater turtle, Chelodina longicollis, to determine the effect of adult roadkill (death by collision with motor vehicles), which is increasing, and reduced recruitment through nest predation from introduced European red foxes ( Vulpes vulpes). We also modeled management scenarios to test the effectiveness of headstarting, fox management, and measures to reduce mortality on roads. Only scenarios with headstarting from source populations eliminated all risks of extinction and allowed population growth. Small increases in adult mortality (2%) had the greatest effect on population growth and extinction risk. Where threats simultaneously affected other life-history stages (e.g., recruitment), eliminating harvest pressures on adult females alone did not eliminate the risk of population extinction. In our models, one source population could supply enough hatchlings annually to supplement 25 other similar-sized populations such that extinction was avoided. Based on our results, we believe headstarting should be a primary tool for managing freshwater turtles for which threats affect multiple life-history stages. We advocate the creation of source populations for managing freshwater turtles that are greatly threatened at multiple life-history stages, such as depredation of eggs by invasive species and adult mortality via roadkill. [ABSTRACT FROM AUTHOR]

Roads are detrimental to wildlife populations that require contiguous networks of terrestrial and aquatic habitats. Many species of freshwater turtles are sensitive to habitat fragmentation caused by roads, and are susceptible to road mortality during overland migrations. The common long-necked turtle ( C helodina longicollis) is an Australian freshwater turtle that frequently moves between wetlands, and so populations may incur negative impacts from road effects. Here, we assessed the relationship between C . longicollis and road density and landscape variables within populations inhabiting 20 wetlands distributed throughout greater Melbourne, Australia. The size frequency distribution of C . longicollis at sites surrounded by high road densities was skewed towards larger individuals, but there was no difference in the frequency of juveniles between high and low road density sites. Regression modelling revealed a clear positive relationship between road density and carapace length ( CL) of C . longicollis; the mean CL at a site with the highest road density was predicted to be 23% greater than mean CL at a site surrounded by no roads. Female CL was also positively related to road density. There was a clear positive relationship between wetland age and CL, although this relationship was not as strong. While there was no relationship evident between road density and the proportion of female C . longicollis at a site, more females were captured at smaller ephemeral sites surrounded by a high proportion of green open space and located near drainage lines. We did not find evidence of sex-related differences in road effects. These results suggest that roads may be affecting C . longicollis in the study area, but the direct cause of any effects is difficult to identify. [ABSTRACT FROM AUTHOR]

Reducing predation by introduced predators on seasonally vulnerable prey is of interest to biodiversity and game managers around the world. In Australia, the Red Fox ( Vulpes vulpes) is a significant predator of freshwater turtle nests, destroying up to 93% of nests. We used a nonrandomized intervention study to assess the effectiveness of a short-term (3-week) but broad-scale baiting operation in reducing the level of nest predation on artificial turtle nests around a complex lake system during a major flooding event in north-western Victoria. Estimates of fox occupancy declined from 0.58 (0.44-0.70 95% CI) to 0.34 (0.21-0.46 95% CI) following fox control. Modelling of nest-survival rates indicated there was no significant change in survival rates. Effective short-term predator control to protect seasonally vulnerable prey is desirable and achievable. Knowledge of underlying predator density, predator-bait encounter and consumption rates, and the optimal duration of short-term control is needed to reduce the risk to prey. [ABSTRACT FROM AUTHOR]

Context. Species vary broadly in their ability to adapt to urbanisation. Freshwater turtles are vulnerable to the loss and degradation of terrestrial and aquatic habitat in urban environments. There have been few publications investigating impacts of urbanisation on freshwater turtles in Australia. Aims. We investigated the effects of urbanisation on the distribution and abundance of the eastern long-necked turtle (Chelodina longicollis) in greater Melbourne. Methods. We examined occurrence andrelative abundance of C. longicollis at 55 wetlands across an urban-rural gradient in relation to site- and landscape-level factors. Occupancy was modelled using the program PRESENCE, and incorporated landscape and habitat covariates. A negative binomial regression model was used to examine the influence of landscape and habitat factors on relative abundance by using WinBUGS. Key results. C. longicollis occupied 85% of the 55 wetlands we surveyed, and we found no evidence that wetland occupancy was influenced by the variables we measured. However, relative abundance was highest at wetlands with low water conductivity and heavy metal pollution, and in wetlands furthest from rivers. Conclusions. C. longicollis appears to be resilient to urbanisation and is likely to persist in urban landscapes, possibly because of the creation of new wetlands in Australian cities. However, long-term studies focussed on demographic parameters, or survivorship, may elucidate as yet undetected effects of urbanisation. Although no specific management recommendations may be necessary for C. longicollis in urban areas at this time, this species may be in decline in non-urban areas as a result of climatic changes and wetland drying. Implications. Our findings suggest that caution is required before drawing generalised conclusions on the impacts of urbanisation on turtles, as the effects are likely to be species-specific, dependent on specific ecology and life-history requirements. Further studies are required to ascertain these relationships for a wider array of species and over longer time spans. [ABSTRACT FROM AUTHOR]

The article presents a study which performed hematologic and serum biochemical analyses on wild-caught, gravid, Australian freshwater chelonians, particularly long-necked turtles Chelodina (C.) oblonga, common long-necked turtles C. longicollis, and Murray River turtles Emydura macquarii. Erythrocyte morphology for all species was typical of that previously described in chelonians. The observed eosinophilia in parasitized C. longicollis may reportedly be associated with hemoparasitism.

Urbanization is one of the most rapidly expanding forms of habitat alteration worldwide. Wildlife differs in their responses to urbanization depending upon species and site-specific factors. We used capture-mark-recapture to examine the abundance, population demographics, growth, and movements of the eastern long-necked turtle (Chelodina longicollis) in Australia over 1 year in a suburban environment and an adjacent nature reserve during drought. Contrary to expectations, sex ratios, injury incidence, and frequency of juvenile size classes did not differ between turtles in the suburbs and the nature reserve. Moreover, turtles in the suburbs were nearly 3 times more abundant, grew 5 times faster, and had populations comprised of more adults in the larger size classes than nature reserve populations. These findings, together with net movements from the nature reserves into the suburbs, suggest that suburban water bodies were the higher quality habitat, effectively buffering turtles from temporal fluctuations in environmental conditions during drought. However, reserve managers and urban planners need to recognize that suburban water bodies have the potential to attract turtles from nearby reserves during drought, and that even low levels of persistent mortality during these travels across reserve boundaries may have consequences for populations of long-lived vertebrates. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the inter-wetland connectivity in a southern national park in Australia. The study had an intensive monitoring on the movements of freshwater turtles thru capture-mark-recapture over a three-year period. It revealed that a high percentage of turtles are moving between wetlands indicating the disadvantage of wetlands representing the minimum habitat unit harboring. The study concludes the need for understanding the spatial and temporal variation in intra-patch processes as well as the expected movement responses of animals.

The article focuses on the urban populations of freshwater turtles Chelodina longicollis and Emydura macquarii dharuk in Sydney, New South Wales. It states that turtles share habitat within urban Sydney while in non-urban, the dominant between the two is the C. longicollis. It tells that both species are placed in precarious position due to continuous habitat degradation, potential competition, and low recruitment. It notes that the low number of Emydura m. dharuk is due to the lack of mobility. On the other hand, C. longicollis has a great number because of propensity for overland movement in which they are used more in urban waters.

Aquatic animals inhabiting temporary wetlands must respond to habitat drying either by estivating or moving to other wetlands. Using radiotelemetry and capture-mark- recapture, we examined factors influencing the decisions made by individuals in a population of freshwater turtles (Chelodina longicollis) in response to wetland drying in southeastern Australia. Turtles exhibited both behaviors, either remaining quiescent in terrestrial habitats for variable lengths of time (terrestrial estivation) or moving to other wetlands. Both the proportion of individuals that estivated terrestrially and the time individuals spent in terrestrial habitats increased with decreasing wetland hydroperiod and increasing distance to the nearest permanent wetland, suggesting behavioral decisions are conditional or state dependent (i.e., plastic) and influenced by local and landscape factors. Variation in the strategy or tactic chosen also increased with increasing isolation from other wetlands, suggesting that individuals differentially weigh the costs and benefits of residing terrestrially vs. those of long-distance movement; movement to other wetlands was the near universal strategy chosen when only a short distance must be traveled to permanent wetlands. The quality of temporary wetlands relative to permanent wetlands at our study site varies considerably and unpredictably with annual rainfall and with it the cost-benefit ratio of each strategy or tactic. Residency in or near temporary wetlands is more successful during wet periods due to production benefits, but movement to permanent wetlands is more successful, or least costly, during dry periods due to survival and body condition benefits. This shifting balance may maintain diversity in response of turtles to the spatial and temporal pattern in wetland quality if their response is in part genetically determined. [ABSTRACT FROM AUTHOR]

Abstract: While the importance of nearby terrestrial habitats is gaining recognition in contemporary wetland management strategies, it is rarely recognized that different wetlands are often diverse in their functions of meeting the annual or life-cycle requirements of many species, and that migration between these wetlands is also critical. Using radio-telemetry, we examined terrestrial habitat use and movements of 53 eastern long-necked turtles (Chelodina longicollis) in an area of southeast Australia characterized by spatially diverse and temporally variable wetlands. Male and female C. longicollis exhibited a high degree of dependence on terrestrial habitat, the majority (95%) of individuals using sites within 375m of the wetland. Turtles also associated with more than one wetland, using permanent lakes during droughts and moving en masse to nearby temporary wetlands after flooding. Turtles used 2.4±0.1 (range=1–5) wetlands separated by 427±62 (range=40–1470)m and moved between these wetlands 2.6±0.3 (range=0–12) times over the course of a year. A literature review revealed that several species of reptiles from diverse taxonomic groups move between wetlands separated by a mean minimum and maximum distance of 499–1518m. A high proportion of studies attributed movements to seasonal migrations (55%) and periodic drought (37%). In such cases we argue that the different wetlands offer complimentary resources and that managing wetlands as isolated units, even with generous terrestrial buffer zones, would not likely conserve core habitats needed to maintain local abundance or persistence of populations over the long term. Core management units should instead reflect heterogeneous groups of wetlands together with terrestrial buffer zones and travel corridors between wetlands. [Copyright &y& Elsevier]