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We present a method to construct superintegrable n -component Lotka–Volterra (LV) systems with 3 n − 2 parameters. We apply the method to LV systems with n components for 1 < n < 6 , and present several n -dimensional superintegrable families. The LV systems are in one-to-one correspondence with trees on n vertices. [ABSTRACT FROM AUTHOR]

We present a novel numerical method for solving ODEs while preserving polynomial first integrals. The method is based on introducing multiple quadratic auxiliary variables to reformulate the ODE as an equivalent but higher-dimensional ODE with only quadratic integrals to which the midpoint rule is applied. The quadratic auxiliary variables can subsequently be eliminated yielding a midpoint-like method on the original phase space. The resulting method is shown to be a novel discrete gradient method. Furthermore, the averaged vector field method can be obtained as a special case of the proposed method. The method can be extended to higher-order through composition and is illustrated through a number of numerical examples. [ABSTRACT FROM AUTHOR]

The article discusses research on a novel approach to determining the sex of Lachesis stenophrys, a Serpentes Viperidaei, using radiography. The study identified and examined radiopaque structures and features of the adult and juvenile species including hemipene adornments distal to the cloacal region. The benefits of radiography are highlighted including shorter duration of assessment of each snake and lack of false positive results.

Over recent decades, Chinese giant salamanders Andrias spp. have declined dramatically across much of their range. Overexploitation and habitat degradation have been widely cited as the cause of these declines. To investigate the relative contribution of each of these factors in driving the declines, we carried out standardized ecological and questionnaire surveys at 98 sites across the range of giant salamanders in China. We did not find any statistically significant differences between water parameters (temperature, dissolved oxygen, ammonia, nitrite, nitrate, salinity, alkalinity, hardness and flow rate) recorded at sites where giant salamanders were detected by survey teams and/or had been recently seen by local respondents, and sites where they were not detected and/or from which they had recently been extirpated. Additionally, we found direct and indirect evidence that the extraction of giant salamanders from the wild is ongoing, including within protected areas. Our results support the hypothesis that the decline of giant salamanders across China has been primarily driven by overexploitation. Data on water parameters may be informative for the establishment of conservation breeding programmes, an initiative recommended for the conservation of these species. [ABSTRACT FROM AUTHOR]

Frogs of the genus Indirana are endemic to India. Previous research on these frogs has focussed on taxonomy and systematics but their behaviour remains largely understudied. Here we report the breeding behaviour of Indirana cf. tysoni, including nest building, male to male combat, inguinal amplexus, egg clutch guarding, tadpoles and polymorphism. We also analyse advertisement calls and present a comparative analysis with previously published data. Lastly, we discuss the need to study these breeding behaviours in-depth in order to help frame appropriate conservation plans. [ABSTRACT FROM AUTHOR]

The article focuses on Diploderma chapaense, a lizard species found in northern Vietnam and southern China, revealing information about its clutch size and instances of predation, including the identification of Lycodon chapaensis as a predator.

The genus Megophrys is known to harbour morphological cryptic species diversity. During field work on Vietnam's third highest peak, Mount Ky Quan San, north-west Vietnam, we collected specimens of a new species of Megophrys at two locations more than 2000 m above sea level (asl). Phylogenetic analyses using mitochondrial markers place the new species within the subgenus Panophrys, a primarily Chinese radiation within the genus Megophrys. We describe the species based on an all-male type series and distinguish it from all other Megophrys species from mainland Southeast Asia, north of the Isthmus of Kra and nearby provinces of China (Yunnan, Guangxi and Guizhou) based on morphological, molecular and bioacoustic data. The new species is inferred to form a clade along with M. hoanglienensis and M. fansipanensis; it is syntopic with the former but has a non-overlapping range with the latter. Uncorrected p distances for the 16S rDNA and CO1 genes between the new species and closest relatives exceed values observed between other closely related species in the Panophrys subgenus. The new species is most similar to M. fansipanensis in terms of morphology, and several call parameters also overlap with this species; however, these two species call at different times of year. This is the fourth likely range-restricted and Endangered Megophrys species described from the Hoang Lien Range since 2017, and this discovery further highlights the significance of the Hoang Lien Range for Vietnam's amphibian diversity. [ABSTRACT FROM AUTHOR]

Identifying individual animals is important for studying populations and for the optimal management of individual animals in captivity. In the absence of natural markings that discriminate individuals, such identification may require animals to be marked by researchers. Amphibians are challenging subjects to mark due to their small size and sensitive, permeable and frequently shed skin. Visible Implant Elastomer (VIE) has been widely used to mark amphibians, but no long-term study has validated this technique in caecilian amphibians. We anaesthetised and attempted to VIE mark seven Herpele squalostoma and one Microcaecilia unicolor held at ZSL London Zoo. No specimens suffered ill effects of anaesthesia or VIE injection, but mean persistence of marks was 191 days in H. squalostoma suggesting that this marking technique is not suitable for identifying individuals of this species in the long-term. We were unable to inject VIE into the M. unicolor and/or the elastomer was not visible through the darkly pigmented skin. Further research is required to develop methods for long-term marking of a diversity of caecilians. [ABSTRACT FROM AUTHOR]

The article focuses on first documented breeding of the Lachesis stenophrys (Central American Bushmaster) located at ZSL London Zoo, England. It mentions that genus Lachesis is unique among new world pit vipers as it lays eggs rather than giving birth to live young. It also discusses husbandry and reproductive biology of the species.

Calculating cost-effective solutions to particle dynamics in viscous flows is an important problem in many areas of industry and nature. We implement a second-order symmetric splitting method on the governing equations for a rigid spheroidal particle model with torques, drag and gravity. The method splits the operators into a vector field that is conservative and one that takes into account the forces of the fluid. Error analysis and numerical tests are performed on perturbed and stiff particle-fluid systems. For the perturbed case, the splitting method greatly improves the solution accuracy, when compared to a conventional multistep method, and the global error behaves as O (ε h 2) for roughly equal computational cost. For stiff systems, we show that the splitting method retains stability in regimes where conventional methods blow up. In addition, we show through numerical experiments that the global order is reduced from O (h 2 / ε) in the perturbed regime to O (h) in the stiff regime. [ABSTRACT FROM AUTHOR]

The article reports the first known prey item of the recently described species, Cyrtodactylus kingsadai, in southern Vietnam, which was an annelid worm, and provides information about the fieldwork conducted to collect the lizard specimen.

The IUCN Red List of Threatened Species (Red List) details the extinction risk of the world's species and presents an important biodiversity indicator for conservation policy. Its continued utility relies on it containing up-to-date information on the extinction risk of species. This requires both regular reassessments and the timely assessment of newly described species. We provide an overview of the status of amphibian Red List assessments to highlight the difficulties of keeping assessments updated for species groups with high rates of species description. Since the publication of the IUCN's Global Amphibian Assessment in 2004, description rates of new species and assessment rates were initially similar; yet while the former has remained consistent, the latter has recently sharply declined. Currently 61.3% of amphibian species are either Not Evaluated or have out-of-date assessments. The situation is particularly problematic in countries with the richest amphibian diversity, which typically have the highest rates of amphibian species discovery and face the greatest threats. Efforts to keep the Red List up-to-date are primarily limited by funding, we estimate that an annual investment of US $170,478–$319,290 is needed to have an up-to-date Red List for amphibians. We propose suggestions to increase assessment rates by improving the availability of data relevant to the process: authors of species descriptions or taxonomic revisions should publish information relevant to Red List assessments. Taxonomic journals should suggest inclusion of such information in their author guidelines. We suggest that contributors with significant input into assessments should be rewarded with co-authorship of published assessments. [ABSTRACT FROM AUTHOR]

Tree-runner lizards, Plica plica are neo-tropical ground lizards, native to South America. ZSL London Zoo has bred this species to the second generation (F2); and the 2.1 founder group has produced six clutches with a mean average of three eggs. The eggs were all removed for incubation, producing 11 viable hatchlings. The first F2 breeding took place in September 2015, and a clutch of two eggs were incubated producing two viable hatchlings. This paper describes the captive husbandry and breeding of Plica plica at ZSL London Zoo, and serves to make some preliminary comparisons to wild data to suggest further areas of research and improvements for captive husbandry. [ABSTRACT FROM AUTHOR]

Six Polypedates otilophus were reared from small juveniles to adult breeding size over a period of 18 months. An account of captive husbandry and breeding is provided. Clutch size ranged from 44-119 eggs. Eggs hatched after ten days and tadpoles attained total lengths of 85 mm. Metamorphosis took 74 - 84 days at 22 - 26 °C. [ABSTRACT FROM AUTHOR]

Maintaining caecilians in captivity provides opportunities to study life-history, behaviour and reproductive biology and to investigate and to develop treatment protocols for amphibian chytridiomycosis. Few species of caecilians are maintained in captivity and little has been published on their husbandry. We present data on substrate preference in a group of eight Central African Geotrypetes seraphini (Duméril, 1859). Two substrates were trialled; coir and Megazorb (a waste product from the paper making industry). G. seraphini showed a strong preference for the Megazorb. We anticipate this finding will improve the captive management of this and perhaps also other species of fossorial caecilians, and stimulate evidence-based husbandry practices. [ABSTRACT FROM AUTHOR]

The article compares the trade in amphibians and reptiles in Great Britain between 1992-1993 and 2004-2005. The number of amphibian and reptile species in the trade rose by less than a third in both trading periods. Species increases were higher for amphibians, chelonians and lizards, and species turnover between the two trading periods was 31%. Prices of snake species that were popular in the trade fell between the periods. Changes in the price of chelonians were linked with the changes in trade regulations while popularity and overhead costs are among the reasons for amphibian price increases.

The article discusses a study on the environmental parameters and implications for captive husbandry of Typhlonectid caecilian, Typhlonectes natans (T. natans), in Colombia. The study observed Typhlonectes natans disperse into floodplains during the rainy season. The study concluded that Typhlonectes natans, which are widely distributed and kept in captivity, allow captive management of the species. The environmental parameters of the natural habitat occupied by T. natans are recorded. The occurrence of T. natans in lagoons and streams in the wet season reportedly provides an overview of seasonal movement of the species.

The article focuses on the captive husbandry and breeding of the shovel-footed squeaker Arthroleptis stenodactylus. The sexual maturity of the captive species is estimated at less than one year. Crickets consist majority of the live invertebrates diet of Arthroleptis stenodactylus. Sphagnum moss and bark chip were used to lay eggs which were left in-situ and took about one month to hatch. Dilute Ivermectin was used to bathe the frogs for one hour, once a week, and for three weeks as treatment for parasites.

• An efficient geometric method better calculates preferential concentration of particles. • A contractivity-preserving splitting method preserves the sum of the Lyapunov spectrum. • The centrifuge effect is also mimicked in the numerical solution. • Non-divergence-free interpolation can erroneously cluster particles. • Matrix-valued RBFs are equivalent to interpolation via regularized Stokeslets. A geometric numerical method for simulating suspensions of spherical and non-spherical particles with Stokes drag is proposed. The method combines divergence-free matrix-valued radial basis function interpolation of the fluid velocity field with a splitting method integrator that preserves the sum of the Lyapunov spectrum while mimicking the centrifuge effect of the exact solution. We discuss how breaking the divergence-free condition in the interpolation step can erroneously affect how the volume of the particulate phase evolves under numerical methods. The methods are tested on suspensions of 104 particles evolving in a discrete cellular flow field. The results are that the proposed geometric methods generate more accurate and cost-effective particle distributions compared to conventional methods. [ABSTRACT FROM AUTHOR]

The article offers information the "Failure to detect the Chinese giant salamander (Andrias davidianus) in Fanjingshan National Nature Reserve, Guizhou Province, China" by the authors. Topics discussed include survey techniques and conservation status of giant salamanders, poaching of the protected species and conservation management of A. davidianus, and activity rhythm and reproductive behaviours of Andrias davidianus.

The article reports on initiatives to protect the endangered mountain chicken Leptodactylus fallax, which is considered as the largest amphibian in the Caribbean region and is restricted to the islands of Dominica and Montserrat in Eastern Caribbean. Topics discussed include factors that contributed to the extinction of the specie including its consumption as food, the description of the mountain chicken's reproductive biology and information dissemination among locals to conserve the specie.

The article discusses research on the different aspects of captive husbandry of Taylor's Bug-eyed Frog or Theloderma stellatum. The researcher studied the management, reproduction and health of T. stellatum while in captivity. He found out that T. stellatum bred from the months of April to October, which are considered warmer months. He also observed that the frogs readily oviposited right on the surface of any over-hanging water in captivity, despite their practice of breeding in tree holes when in the wild.

Multiple clutching, with two or three successful clutches raised in a single breeding season, is reported from two females of Leptodactylus fallax in two European zoos. Previously, only single clutches were known to be raised by this species. Multiple clutching is perhaps unexpected in this species due to its resource-heavy parental care behaviour. Potential drivers of multiple clutching, including food resourcing and timing and size of initial clutches, are discussed. [ABSTRACT FROM AUTHOR]

The article discusses research on a novel approach to determining the sex of Lachesis stenophrys, a Serpentes Viperidaei, using radiography. The study identified and examined radiopaque structures and features of the adult and juvenile species including hemipene adornments distal to the cloacal region. The benefits of radiography are highlighted including shorter duration of assessment of each snake and lack of false positive results.

Climate change is one of the major drivers of biodiversity loss. Among vertebrates, amphibians are one of the more sensitive groups to climate change due to their unique ecology, habitat requirements, narrow thermal tolerance and relatively limited dispersal abilities. We projected the influence of climate change on an endemic toad, Malabar Tree Toad (Pedostibes tuberculosus; hereafter MTT) from the Western Ghats biodiversity hotspot, India, for two different shared socio-economic pathways (SSP) using multiple modeling approaches for current and future (2061–2080) scenarios. The data used predominantly comes from a citizen science program, 'Mapping Malabar Tree Toad' which is a part of the Frog Watch citizen science program, India Biodiversity Portal. We also evaluated the availability of suitable habitats for the MTT in Protected Areas (PAs) under the current and future scenarios. Our results show that annual precipitation was the most important bioclimatic variable influencing the distribution of MTT. We used MaxEnt (MEM) and Ensemble (ESM) modeling algorithms. The predicted distribution of MTT with selected environmental layers using MEM was 4556.95 km2 while using ESM was 18,563.76 km2. Overlaying PA boundaries on predicted distribution showed 37 PAs with 32.7% (1491.37 km2) and 44 PAs with 21.9% (4066.25 km2) coverage for MEM and ESM respectively. Among eight future climate scenarios, scenarios with high emissions showed a decreased distribution range from 33.5 to 68.7% of predicted distribution in PAs, while scenarios with low emissions showed an increased distribution range from 1.9 to 111.3% in PAs. PAs from the Central Western Ghats lose most suitable areas with a shift of suitable habitats towards the Southern Western Ghats. This suggests that MTT distribution may be restricted in the future and existing PAs may not be sufficient to conserve their habitats. Restricted and discontinuous distribution along with climate change can limit the dispersal and persistence of MTT populations, thus enhanced surveys of MTT habitats within and outside the PAs of the Western Ghats are an important step in safeguarding the persistence of MTT populations. Overall, our results demonstrate the use of citizen science data and its potential in modeling and understanding the geographic distribution and the calling phenology of an elusive, arboreal, and endemic amphibian species. [ABSTRACT FROM AUTHOR]

The Critically Endangered Cantor's giant softshell turtle Pelochelys cantorii is a freshwater turtle found in South and Southeast Asia. Its population is declining because of habitat destruction and alteration, and hunting for its meat. Data on the species' ecology, behaviour, population size, distribution and threats are limited, and previous surveys undertaken in India have failed to detect individuals in the wild. This lack of data hinders strategic conservation planning. Ecologists and conservationists increasingly utilize local ecological knowledge to determine the status and gain insights into the ecology of threatened and rare species that are difficult to detect in field studies. To examine the historical and current occurrence of Cantor's giant softshell turtle, we conducted community interviews along the Chandragiri River in Kerala, India. With data from these interviews, we identified multiple sites where the species continues to occur. Older respondents and those that used the river for fishing and irrigation were more likely to report sightings of the species. Our findings also improved knowledge about the turtles' seasonal and diel activity patterns. A network of key informants identified through the interviews provided information on turtle bycatch, sightings and nesting. This network is being utilized for the continued monitoring of the species and could help in devising evidence-based management strategies for softshell turtles in India. These methods can also be adopted more widely for other threatened species of freshwater turtles globally. [ABSTRACT FROM AUTHOR]

Globally, amphibians are declining more rapidly than any other vertebrate group. A general shortage of funding for the support of focused scientific studies led us to investigate local and traditional ecological knowledge as an alternative data source for amphibian conservation. In this context, we undertook a questionnaire-based interview survey with forest-dwelling indigenous and non-indigenous communities across the Anamalai Hills, within the southern Western Ghats of India, to gather ecological knowledge on three cryptic and threatened frog species. Our results suggest that local communities possess ecological knowledge of frogs and that the magnitude of this knowledge is influenced by gender, community type, education, and age. Accuracy of local knowledge was primarily influenced by the morphological distinctiveness of the focal species, but cultural association and utilisation were also important factors especially for the enigmatic purple frog Nasikabatrachus sahyadrensis, which has uses in medicine and amulets. [ABSTRACT FROM AUTHOR]

The article reports on the calling site of the Kakhien Hills spadefoot toad Brachytarsophrys feae. It notes that frogs of the genus Brachytarsophrys are deemed rare and the ecology of its five species poorly known. B. feae is known from Northern Vietnam, northeast Myanmar, and northern Thailand among others. It observed specimens found in Tam Dao national park in Vinh Phu province in northern Vietnam. Six males were heard vocalising between 19:30 and 22:30 from small caves under rocky overhangs in shallow, slow moving clear water stream. It believes that males of the species may form chorusing groups with strong site fidelity as reported for other Megophryd frogs. The frogs dug out tunnels under rocks in the sandy substrate of the stream, calling from them to attract females.

Overexploitation has driven catastrophic declines in most turtle species in Asia. Many turtles are seized annually by law enforcement officers; unfortunately, seized turtles often lack associated information on their provenance. There is also taxonomic confusion regarding the clear delineation of turtle species and subspecies in Asia. This lack of provenance data and taxonomic uncertainty is problematic as it may preclude release, make appropriate release sites hard to select, or result in genetic pollution when animals are released. In this study, we amassed and analyzed the largest number of genetic samples of the critically endangered big-headed turtle (Platysternon megacephalum) to date. Our phylogenetic and network results based on nearly 500 sequences of a mitochondrial ND4 fragment corroborate the earlier hypothesis that only two of the three currently recognized subspecies have strong molecular support and that there is greater genetic structuring within one subspecies than has been previously reported. The vast majority of P. megacephalum confiscated from the trade in Vietnam belong to Subclade 3 of P. m. peguense, and this subclade is the most broadly distributed taxon of the big-headed turtle in Vietnam based on samples with known localities. Nonetheless, for the other two subclades, all their samples originate from the trade and could not be assigned to any geographic provenance because of the lack of wild-caught samples. In addition, our results reveal two trade centers of the species, Quang Ninh Province on the border between China and Vietnam and Kon Tum Province in the Central Highlands. However, smaller animal seizures occur across the range of the species in Vietnam. While the data presented here have facilitated the selection of appropriate release sites for confiscated P. megacephalum, the significant costs of genetic screening and the shortage of samples from wild animals with good localities hinder the rewilding efforts, especially for conservation practitioners working in countries where conservation activities are not well funded and research on poorly studied species is still limited. Nevertheless, we urge that wildlife translocations include robust pre-translocation genetic screening to ensure that all individual animals are reintroduced at appropriate sites. [ABSTRACT FROM AUTHOR]

The interest in the welfare of zoo animals, from both the public and the scientific community, has long been biased towards mammals. However, growing evidence of the complex behavioural repertoires of less charismatic animals, such as reptiles, reveals the necessity to better comply with their welfare needs in captivity. Here, we present the effects of an enclosure change towards a more natural habitat in captive Galapagos tortoises (Chelonoidis spp.) held at ZSL London Zoo. Using behavioural observations, we found that the tortoises habituated to their new enclosure in six days. This represents the first quantification of habituation latency to a new enclosure in a reptile model to our knowledge—which is important information to adapt policies governing animal moves. The tortoises expressed time budgets more similar to those of wild individuals after their transition to the new enclosure. Interestingly, the hierarchy between the individuals was inverted and more stable after this change in environment. The tortoises interacted less often, which led to a decrease in the frequency of agonistic encounters. We also found that higher ambient sound volume was associated with increased likelihood of interactions turning into fights. Taken together, our results demonstrate the potential of appropriate enclosure design to improve reptile welfare. [ABSTRACT FROM AUTHOR]

Staggering food availability through a delivery device is a common way of providing behavioural enrichment as it is usually thought to increase the amount of natural behaviour due to the unpredictability of the food source. Tree-runner lizards ( Plica plica ) are a Neotropical, scansorial, insectivorous species. We provided these lizards with an enrichment device that slowly released insect prey and tested its effect on the activity and frequency of a number of behaviours in comparison with a scatter control (where prey items were broadcast in the enclosure; standard food presentation for captive insectivorous lizards) and a non-feeding control. Both types of food increased activity and counts of several behaviours in comparison with the non-feeding control. However, we found the provision of the behavioural enrichment device led to a significantly lower frequency of almost all analysed behaviours in comparison with scatter control trials, mainly in behaviours associated with activity (unsuccessful strikes (= unsuccessful capture of prey) (p = 0.004), locomotion (p = 0.004), alertness (p = 0.004) and the number of times a boundary in the enclosure was crossed ie. activity (p = < 0.001)). The frequencies significantly increased in the enrichment trials (relative to the scatter control) were the number of successful strikes (=successful capture of prey; p = <0.001) and targeting prey (p = <0.001). There was no significant difference in latency to first strike (p = 0.24), duration of hunting activity (p = 0.83) or enclosure use (p = >0.05) between scatter and enriched trials. The relative success of the scatter feed in promoting activity and increasing hunting difficulty was likely partly due to the enclosure design, where the complex physical environment contributed to the difficultly in catching the prey. However, when the feeding duration and enclosure use was analysed there was no significant difference between the scatter control and enrichment trails. The results from this study highlight the importance of evaluating enrichment strategies, and the role of complex enclosure design in creating effective enrichment for insectivores, which can contribute to their welfare in captivity. [ABSTRACT FROM AUTHOR]

Sexual dimorphism is commonly encountered in amphibians. Its presence and its ontogeny in a given species has implications for ecology, conservation and captive husbandry. We monitored changes in length and mass of captive mountain chicken frogs Leptodactylus fallax. Initially, sexes were no different in snout-vent length or mass, but by about 17 months after metamorphosis females became significantly larger and heavier than males. Diverging growth trajectories between male and female frogs appeared to coincide with the development of secondary sexual characters in males, indicating sexual maturity, while female frogs did not produce nests until the following breeding season, suggesting later reproductive maturity. The absence of similar dimorphism in other large leptodactylids suggests that its presence in L. fallax may be linked to its unique and energy-intense reproductive strategy, which involves extended maternal provisioning of their young. [ABSTRACT FROM AUTHOR]

Animal behavior and welfare science can form the basis of zoo animal management. However, even basic behavioral data are lacking for the majority of amphibian species, and species-specific research is required to inform management. Our goal was to develop the first ethogram for the critically endangered frog Xenopus longipes through observation of a captive population of 24 frogs. The ethogram was applied to produce a diurnal activity budget and to measure the behavioral impact of a routine health check where frogs were restrained. In the activity budget, frogs spent the vast majority of time swimming, resting in small amounts of time devoted to feeding, foraging, breathing, and (in males) amplexus. Using linear mixed models, we found no effect of time of day or sex on baseline behavior, other than for breathing, which had a greater duration in females. Linear mixed models indicated significant effects of the health check on duration of swimming, resting, foraging, feeding, and breathing behaviors for all frogs. This indicates a welfare trade-off associated with veterinary monitoring and highlights the importance of non-invasive monitoring where possible, as well as providing candidates for behavioral monitoring of acute stress. This investigation has provided the first behavioral data for this species which can be applied to future research regarding husbandry and management practices. [ABSTRACT FROM AUTHOR]

Maintaining Gymnophiona in captivity provides opportunities to study the behaviour and life-history of this poorly known Order, and to investigate and provide species-appropriate welfare guidelines, which are currently lacking. This study focuses on the terrestrial caecilian Herpele squalostoma to investigate its sensitivity to disturbances associated with routine husbandry needed for monitoring and maintaining adequate wellbeing in captivity. Fossorial caecilians gradually pollute their environment in captivity with waste products, and substrate must be replaced at intervals; doing so disturbs the animals directly and via destruction of burrow networks. As inappetence is frequently associated with stress in amphibians, the percentage consumption of offered food types, river shrimp (Palaemon varians) and brown crickets (Gryllus assimilis), was measured as an indicator of putative stress following three routine substrate changes up to 297 days post-substrate change. Mean daily variation in substrate temperatures were also recorded in order to account for environmental influences on food consumption, along with nitrogenous waste in tank substrate prior to a substrate change and fresh top soil in order to understand the trade-off between dealing with waste accumulation and disturbing animals. We found a significant negative effect of substrate disturbance on food intake, but no significant effect of prey type. Variations in daily soil temperatures did not have a significant effect on food intake, but mean substrate temperature did. Additionally, substrate nitrogenous waste testing indicated little difference between fresh and tank substrate. In conclusion, this study provides a basis from which to develop further welfare assessment for this and other rarely kept and rarely observed terrestrial caecilian species. [ABSTRACT FROM AUTHOR]

This study compared the resource use of juvenile zoo-living Chinese crocodile lizards, Shinisaurus crocodilurus crocodilurus across three observation windows, spanning nine months, accounting for time of day and lizard age, and under consistent environmental conditions. Lizards showed a significant difference in proportionate resource use, quantified using a modified spread of participation indices between the second and final sampling period, such that with increasing age, resources were more equally utilised. The time of day did not have a significant effect on resource use. Lizards in this study significantly increased their use of water bodies and branches outside the bask zone and decreased their use of the land areas within the bask zones over time. Resource use data suggests the importance of providing enclosures which cater to ontogenetic shifts in captive individuals or within mixed age groupings. [ABSTRACT FROM AUTHOR]

A workshop was held in China in October 2023 to discuss the conservation of the Chinese giant salamander, which is currently categorized as Critically Endangered due to overexploitation and habitat loss. The workshop attendees, representing various stakeholders, agreed on several key actions, including research to resolve taxonomic issues, field surveys to protect remaining populations, and investigations into how salamander farming could benefit conservation efforts. Other actions included refining the process for releasing individuals from farms, advocating for legislative changes, studying the species' behavior and ecology, and implementing better practices to prevent the introduction and transmission of pathogens. [Extracted from the article]

We propose a novel integral model describing the motion of both flexible and rigid slender fibers in viscous flow and develop a numerical method for simulating dynamics of curved rigid fibers. The model is derived from nonlocal slender body theory (SBT), which approximates flow near the fiber using singular solutions of the Stokes equations integrated along the fiber centerline. In contrast to other models based on (singular) SBT, our model yields a smooth integral kernel which incorporates the (possibly varying) fiber radius naturally. The integral operator is provably negative definite in a nonphysical idealized geometry, as expected from the partial differential equation theory. This is numerically verified in physically relevant geometries. We discuss the convergence and stability of a numerical method for solving the integral equation. The accuracy of the model and method is verified against known models for ellipsoids. Finally, we develop an algorithm for computing dynamics of rigid fibers with complex geometries in the case where the fiber density is much greater than that of the fluid, for example, in turbulent gas-fiber suspensions. [ABSTRACT FROM AUTHOR]

The mountain chicken frog (Leptodactylus fallax) is among the 42 % of amphibians threatened with extinction and is dependent upon ex situ populations to recover in the wild. Amphibian captive husbandry is not fully understood and empirical data are required to optimise protocols for each species in captivity. Calcium metabolism and homeostasis are areas of importance in captive husbandry research and have been identified as a challenge in maintaining ex situ populations of L. fallax. We trialled two frequencies (twice and seven times weekly) of calcium supplementation via dusting of feeder insects in two groups of L. fallax juveniles and measured growth and health effects through morphometrics, radiography, ultrasonography and blood and faecal analysis over 167 days, followed by a further 230 days of monitoring on an intermediate diet informed by the initial dataset. We showed that supplementation treatment did not affect growth or health status as measured through blood analysis, radiography and ultrasonography. More frequent supplementation resulted in significantly more radiopaque endolymphatic sacs and broader skulls. Frogs fed more calcium excreted twice as much calcium in their faeces. The intermediate diet resulted in previously lower supplementation frogs approximating the higher supplementation frogs in morphometrics and calcium stores. Comparison with radiographic data from wild frogs showed that both treatments may still have had narrower skulls than wild animals, but mismatching age class may limit this comparison. Our data may be used to inform dietary supplementation of captive L. fallax as well as other amphibians. [ABSTRACT FROM AUTHOR]

In order to better understand the impacts and treatment of infection with Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal) it is important to document host species, the effect of infection and response to treatment protocols. Here we report asymptomatic Bd infection detected through duplex qPCR screening of three Mexican ambystomatid salamanders; Ambystoma andersoni, Ambystoma dumerilii and Ambystoma mexicanum at three zoo collections, and A. andersoni and A. mexicanum in a private collection. Bsal was tested for but not detected. We also report the effectiveness and side effects of five treatment protocols in these species. Using the antifungal agent itraconazole, A. dumerilii were cleared of infection without side-effects using the granulated preparation (Sporanox). Morbidity and mortality occurred when A. dumerilii and A. andersoni were treated using a liquid oral preparation of the itraconazole (Itrafungol); infection was successfully cleared in surviving specimens of the latter species. Ambystoma mexicanum was successfully cleared without any side-effects using Itrafungol. Mortality and morbidity were likely caused by toxic effects of some component on the liquid preparation of itraconazole, but aspects of water quality and husbandry cannot be ruled out. [ABSTRACT FROM AUTHOR]

Aquatic predators must forage for prey in a complex three-dimensional environment where the availability of different prey types with different spatial niches may vary. Aquatic predators have evolved a number of ways in which they may respond to this variation, including phenotypic adaptation and behavioural modulation. We investigated whether clawed frogs (Xenopus longipes) can modulate their foraging behaviour in response to benthic (bloodworms) and pelagic (glassworms) prey species to which they had already been exposed, and whether any response would be elicited by chemosensory prey cues alone. Frogs responded to the presence of prey items by foraging more than in a control treatment (no cues at all) and were able to respond appropriately to prey type, foraging more in the water column for glassworms and on the aquarium floor for bloodworms. This effect was maintained in a second set of trials where frogs were exposed only to the chemosensory cues of the same prey items. These data show that X. longipes can modulate its foraging strategy to match the type of prey available and that this behaviour is at least in part informed by chemosensory cues. [ABSTRACT FROM AUTHOR]

The rhino rat snake Gonyosoma boulengeri is a medium-sized arboreal colubrid snake from southern China and northern Vietnam. Captive specimens maintained at the Zoological Society of London presented little difficulty in husbandry and were found to breed between March and June. A clutch of 9 eggs were laid on the 16 May 2008 and a clutch of 8 eggs were laid on 4 July 2013, following manipulation of the captive environment to reflect natural seasonality for this species. Post-laying incubation temperature was maintained at a constant 28.0 °C and lasted 52 days for the 2008 clutch and 57 days for the 2013 clutch. All individuals from the 2013 clutch had sloughed their skin for the first time by 10 days post-hatching, and five of the six fed, subsequent to sloughing, by 20 days post-hatching. [ABSTRACT FROM AUTHOR]

One-fifth of the world's reptiles are currently estimated as threatened with extinction, primarily due to the immediate threats of habitat loss and overexploitation. Climate change presents an emerging slow-acting threat. However, few IUCN Red List assessments for reptiles explicitly consider the potential role of climate change as a threat. Thus, climate change vulnerability assessments can complement existing Red List assessments and highlight further, emerging priorities for conservation action. Here we present the first trait-based global climate change vulnerability assessment for reptiles to estimate the climate change vulnerability of a random representative sample of 1498 species of reptiles. We collected species-specific traits relating to three dimensions of climate change, sensitivity, low adaptability, and exposure, which we combined to assess overall vulnerability. We found 80.5% of species highly sensitive to climate change, primarily due to habitat specialisation, while 48% had low adaptability and 58% had high exposure. Overall, 22% of species assessed were highly vulnerable to climate change. Hotspots of climate change vulnerability did not always overlap with hotspots of threatened species richness, with most of the vulnerable species found in northwestern South America, southwestern USA, Sri Lanka, the Himalayan Arc, Central Asia and southern India. Most families were found to be significantly more vulnerable to climate change than expected by chance. Our findings build on previous work on reptile extinction risk to provide an overview of the risk posed to reptiles by climate change. Despite significant data gaps for a number of traits, we recommend that these findings are integrated into reassessments of species' extinction risk, to monitor both immediate and slow-acting threats to reptiles. [ABSTRACT FROM AUTHOR]

One-fifth of the world's reptiles are currently estimated as threatened with extinction, primarily due to the immediate threats of habitat loss and overexploitation. Climate change presents an emerging slow-acting threat. However, few IUCN Red List assessments for reptiles explicitly consider the potential role of climate change as a threat. Thus, climate change vulnerability assessments can complement existing Red List assessments and highlight further, emerging priorities for conservation action. Here we present the first trait-based global climate change vulnerability assessment for reptiles to estimate the climate change vulnerability of a random representative sample of 1498 species of reptiles. We collected species-specific traits relating to three dimensions of climate change, sensitivity, low adaptability, and exposure, which we combined to assess overall vulnerability. We found 80.5% of species highly sensitive to climate change, primarily due to habitat specialisation, while 48% had low adaptability and 58% had high exposure. Overall, 22% of species assessed were highly vulnerable to climate change. Hotspots of climate change vulnerability did not always overlap with hotspots of threatened species richness, with most of the vulnerable species found in northwestern South America, southwestern USA, Sri Lanka, the Himalayan Arc, Central Asia and southern India. Most families were found to be significantly more vulnerable to climate change than expected by chance. Our findings build on previous work on reptile extinction risk to provide an overview of the risk posed to reptiles by climate change. Despite significant data gaps for a number of traits, we recommend that these findings are integrated into reassessments of species' extinction risk, to monitor both immediate and slow-acting threats to reptiles. [ABSTRACT FROM AUTHOR]

Captive husbandry and breeding may be pivotal to the successful conservation of many amphibian species, with captive stock providing research subjects, educational tools and animals for release into the wild. Husbandry protocols are missing for many species and sub-optimal for many more, which may limit the success of captive breeding attempts. It has been suggested that observations and environmental data taken from species in nature may be used to infer optimal captive conditions for amphibians. For species where data from the wild are not available, 'analogue', that is closely related but more accessible species, may be used as surrogates to inform captive husbandry to some degree. These hypotheses, although logically cogent, are not well tested in amphibians. In particular, the suitability of analogue species based on some knowledge of basic ecology and biology is frequently not assessed. We show that captive husbandry requirements and breeding stimuli correlate with field data and phenology in wild populations of the midwife toads Alytes obstetricans and A. cisternasii. In particular, the provision of hot summer temperatures following a cold brumation period of suitable duration may be important for breeding the western-central European A. obstetricans. Conversely, the Iberian A. cisternasii responds to hot summer temperatures with a rest period and reproduces in the cooler autumn and winter months. Brooding success was highly variable in A. obstetricans and smaller than records from wild toads, possibly due to the young age of breeding stock. Clutch size was similar in A. cisternasii to records from wild counterparts. Although specific breeding triggers and annual temperature requirements are likely to vary between localities for both species, these observations provide some useful data on the indoor breeding of both species. Our results also highlight the relevance of field data in designing captive husbandry protocols, while illustrating the inappropriateness of using one species as an analogue for the other in terms of husbandry requirements unless basic aspects of natural history, ecology and phenology can be shown to be broadly similar. [ABSTRACT FROM AUTHOR]

The article reports on the inclusion of Trimeresurus cardamomensis in the diet of Bungarus fasciatus, which represents the first documentation of B. fasciatus consuming an arboreal viper.

Rhacophorus pseudomalabaricus is a Critically Endangered, range-restricted frog found in the southern Western Ghats of India. We report new distribution records outside the protected area network in the Cardamom Hills of Kerala State through direct sightings and local ecological knowledge. These records increase the distribution by 12 km to the south-east of its currently known range and increase the altitudinal range of the species to 1600 m asl. We present a preliminary call analysis of the species that is distinct from the call of its nearest congener R. malabaricus. Foam nests, tadpoles and metamorphs were sighted in agricultural land suggesting the importance of these landscapes for breeding. Breeding continues into the month of November extending the known length of its breeding season. Breeding occurred in highly disturbed areas and oviposition sites varied according to the vegetation around breeding sites and included the use of non-native plants. This suggests the need to exercise caution while conducting habitat restoration programs that involve a standard removal of non-native plants. The IUCN Red List status for this species could be revised from 'Critically Endangered' to 'Endangered' in light of our findings. Local ecological knowledge on amphibians could provide supplementary information on distinct species with local names and those that have short periods of activity, which may not be frequently encountered during field surveys. [ABSTRACT FROM AUTHOR]

Published records of amphibians preying on either large spiders or snakes in the wild are rare; this note documents predation by individuals of one amphibian species on both large spiders and snakes. Mountain chicken frogs (Leptodactylus fallax), which are amongst the largest frogs in the world, were observed successfully consuming the theraphosid spiderCyrtopholis femoralison two occasions and attempting to consume another one on a further occasion on Montserrat. They were also found to have consumed the colubrid snakeLiophis juliaeon Dominica. This is the first theraphosid and the fourth snake species identified in the diet ofL. fallax, and this frog is the first confirmed predator ofC. femoralis. [ABSTRACT FROM AUTHOR]