The aim of this study was to assess welfare outcomes of electrical stunning as a means of restraint in farmed grower saltwater crocodiles (Crocodylus porosus). Physical handling of a stunned, unconscious crocodile is far safer for the operator than handling a fully conscious animal. Electroencephalogram (EEG) was recorded before and after the application of electrical stunning at 50 Hz or 400 Hz using an electrical stunner applied to the cranial plate (Position 1: P1–50 Hz; n = 31, P1–400 Hz; n = 29) or immediately behind the skull (Position 2: P2–50 Hz; n = 29; P2–400 Hz; n = 30). For all electrical stuns, percentage total EEG power in a 10-s epoch decreased in the alpha and beta frequency bands; and increased in the delta and lower frequencies bands. All electrical stuns resulted in increased strength of signal, based on the quadratic mean EEG power in all frequency bands of the EEG. Greatest change in power occurred in the delta frequency band, with P1–50 Hz. This was greater than with P2–50 Hz; while decibel change using 400 Hz at either position was intermediate and not significantly different from either. Application of either electrical stunner at position 1 resulted in seizure-like activity and activation in low frequencies, but at position 2 this was not consistent across all animals. The ability of the electrical stunning equipment to consistently induce recoverable unconsciousness could be ranked in decreasing order as: P1–50 Hz > P1–400 Hz = P2–50 Hz > P2–400 Hz. Based on behavioural observations, all animals in the study appeared to stunned however evaluation of duration of EEG changes indicates that use of the electrical stunning equipment at 50 Hz would allow some margin for inaccuracies in tong placement, while achieving a consistently reliable stun.

Stereotypies (a subset of Abnormal Repetitive Behaviour [ARB]) are characterised by an unchanging pattern of behaviour and in captive animals can be associated with poor welfare. Although well known in certain taxa, little is known about both welfare and ARBs in reptiles, especially snakes. We document an instance of an ARB in a captive snake species (Hydrodynastes gigas), set it in the context of husbandry in zoos, and assess efforts to reduce it. The stereotypy consisted of a fixed pattern of movement against the enclosure's viewing window. Ethographic data were used to focally sample the animal's behaviour over several months in the context of different enrichment interventions. Modified Spread of Participation Indices (mSPIs) were also calculated to quantify the evenness of enclosure use. The snake spent considerable portions of time (47% of observations) performing a behaviour that fulfils the criteria for stereotypy. mSPI data suggested a possible welfare impact of the behaviour on the snake. Zoos holding this species globally were surveyed about observations of similar behaviour and one other institution reported similar behaviour. Standard husbandry practice (A) was used alternately in an ABAC format with prey scent trails (B) and modified feeding schedules (C), representing enrichment types based on species’ natural history. Neither stereotyping frequency nor mSPI was found to be significantly affected by any of the enrichments. Our results, interpretation of which is limited by the paucity of data on snakes, uncover stereotypies in snakes and suggest that, as with other taxa, ARBs may be resistant to strategies employed to reduce them.

The internet has expanded opportunities for wildlife traders to conduct business globally, but monitoring this activity is often challenging. As monitoring techniques frequently employ language-based searches for particular words, it is important to understand the language traders use, particularly the nomenclature used to refer to traded species. We recorded advert data from four UK websites, focusing on reptiles, which constitute a large proportion of the international pet trade. We analysed whether the language types used by advertisers to refer to individual reptiles were associated with certain trader characteristics. We found English common names were the most frequent name type used to refer to species, regardless of the geographical location of the seller and the CITES Appendix listing of the species. However, scientific names were recorded in twice as many adverts for threatened and Near Threatened species as in adverts for non-threatened species, and only scientific names were used for three families: Anguidae, Pseudaspididae and Sphaerodactylidae. These findings could inform the creation of tailored keyword detection tools, which must account for the numerous language types in use within online wildlife trade communities. Future studies should examine the nuances of language used by other online wildlife trader communities in other contexts, such as different online platforms or different languages. The ultimate aim of these language detection tools will be to track in detail trends in the online reptile trade, offering a better understanding of potentially unsustainable trade patterns and helping authorities to enforce laws against illegal online reptile trade.

Monitoring of cryptic or threatened species poses challenges for population assessment and conservation, as imperfect detection gives rise to misleading inferences about population status. We used a dynamic occupancy model that explicitly accounted for occupancy, colonization, local extinction and detectability to assess the status of the endemic Critically Endangered Bermuda skink Plestiodon longirostris. During 2015–2017, skinks were detected at 13 of 40 surveyed sites in Bermuda, two of which were new records. Ten observation-level and site-specific covariates were used to explore drivers of occupancy, colonization, extinction and detectability. Sites occupied by skinks tended to be islands with rocky coastal habitat and prickly pear cacti; the same variables were also associated with reduced risk of local extinction. The presence of seabirds appeared to encourage colonization, whereas the presence of cats had the opposite effect. The probability of detection was p = 0.45, and on average, five surveys were needed to reliably detect the presence of skinks with 95% certainty. However, skinks were unlikely to be detected on sites with cat and rat predators. Dynamic occupancy models can be used to elucidate drivers of occupancy dynamics, which in turn can inform species conservation management. The survey effort needed to determine population changes over time can be derived from estimates of detectability.

Although snake populations are suffering numerous local declines, determining the scale of these declines is problematic due to the elusive nature of snakes. Determining the factors associated with species detection is therefore essential for quantifying disturbance effects on populations. From 2017 to 2019, we assessed the detectability associations of five river-associated snake species and all snake detections in general within two logging concessions in Sabah, Malaysian Borneo. Data collected from both stream transects and visual encounter surveys at 47 stream sites were incorporated into an occupancy-modelling framework to determine the climatological, temporal and survey distance associations with species detection probability. Detection probability of riparian snake species was significantly associated with humidity, month (2 spp. each), survey distance and total rainfall over 60 days (1 spp. each). Pooled snake species detectability was significantly positively associated with transect distance and the 2019 El-Niño year, whilst yearly pooled snake species detections in stream transects spiked during El-Niño (2017 = 2.05, 2018 = 2.47, 2019 = 4.5 snakes per km). This study provides new insights into the detectability of riparian rainforest snakes and suggests that future studies should account for short-term (climatological and temporal) and long-term (El-Niño) factors associated with detection probability when surveying and assessing snake populations.

The Critically Endangered Chapman's pygmy chameleon Rhampholeon chapmanorum is endemic to the low elevation rainforest of the Malawi Hills in southern Malawi. Much of this forest has been converted to agriculture and it was uncertain whether chameleon populations have persisted. We used current and historical satellite imagery to identify remaining forest patches and assess deforestation. We then surveyed forest patches for the presence of this chameleon, and assessed its genetic diversity and structure. We estimated that 80% of the forest has been destroyed since 1984, although we found extant populations of the chameleon in each of the patches surveyed. Differentiation of genetic structure was strong between populations, suggesting that gene flow has been impaired. Genetic diversity was not low, but this could be the result of a temporal lag as well as lack of sensitivity in the mitochondrial marker used. Overall, the impact of forest loss is assumed to have led to a large demographic decline, with forest fragmentation preventing gene flow.

Disturbances are critical for maintaining environmental heterogeneity and biodiversity across landscapes. Hurricanes represent a common disturbance in the Caribbean Sea. These storms are predicted to become more frequent and severe as climate shifts. Understanding how island communities respond to disturbances is critical to their conservation. We surveyed Virgin Islands National Park located on the island of St. John in the Caribbean Sea in 2016 and 2018 to evaluate prolonged herpetofauna community response and resistance to hurricanes. These surveys occurred in March 2016, and June 2018, before and after the 2017 hurricane season, when hurricanes Irma and Maria struck St. John. Using visual encounter surveys, vocalisation surveys, and opportunistic encounters, we surveyed trails within the park through five landscape cover types pre- and post-hurricane. We used linear regression to determine differences in diversity and species richness among landscape cover types and between pre- and post-hurricane surveys and non-metric multidimensional scaling to observe associations among species and landscape cover types pre- and post-hurricane surveys. We determined that there were no significant changes in landscape cover and herpetofauna community associations before and after the 2017 hurricane season, indicating that the herpetofauna communities of Virgin Islands National Park are well adapted to hurricane-related disturbance.

Due to conflicts between classic and molecular systematics of Camallanidae, different data types were used for the first time, to better understand the evolutionary history and taxa consistency within this family. Genetic [18S and 28S rDNA; cytochrome c oxidase subunit I (COI) mtDNA], morphological and life history traits were used to infer phylogenies using Bayesian inference, reconstructed from separated and concatenated datasets. The consistency of tree and morphological traits was evaluated using the consistency index. Characters were mapped on the trees and the phylogenetic informativeness of genetic markers was estimated. Phylogenetic informativeness of 18S provided better resolution for outer nodes, COI for inners and 28S had an intermediate profile. New sequences for two camallanid species were obtained. Phylogenies of genetic and concatenated data largely agreed, showing more divergence in the COI dataset, due to its higher mutation rate vs stable morphology for diagnosing higher taxa. No genus sustained monophyly. The lack of autapomorphy and phylogenetic proximity supported the partition of Batrachocamallanus as synonym of Procamallanus and Spirocamallanus, which should not be considered as subgenera. Although traits of buccal capsule, male tail, habitat, host and biogeographic were highly consistent, intrinsic patterns varied according to different taxa assemblages. Morphological systematics of Camallanidae, based on buccal capsule, is artificial for certain taxa.

Toxoplasma gondii (T. gondii) is known for its ability to infect warm-blooded vertebrates. Although T. gondii does not appear to parasitize cold-blooded animals, the occurrence of T. gondii infection in marine mammals raises concerns that cold-blooded animals (frogs, toad, turtles, crocodiles, snakes, and fish) and shellfish are potential sources of T. gondii. Therefore, this systematic review aimed to determine the prevalence of T. gondii in mollusks and cold-blooded animals worldwide. We searched PubMed, ScienceDirect, ProQuest, Scopus, and Web of Science from inception to 1 August 2020 for eligible papers in the English language and identified 26 articles that reported the prevalence of T. gondii in mollusks and cold-blooded animals. These articles were subsequently reviewed and data extracted using a standard form. In total, 26 studies [involving 9 cross-sectional studies including 2988 samples of cold-blooded animals (129 positive cases for T. gondii) and 18 cross-sectional studies entailing 13 447 samples of shellfish (692 positive cases for T. gondii)] were included in this study. Although this study showed that shellfish and cold-blooded animals could be potential sources of T. gondii for humans and other hosts that feed on them, further investigations are recommended to determine the prevalence of T. gondii in shellfish and cold-blooded animals.

Spatial prioritization in systematic conservation planning has traditionally been developed for several to many species and/or habitats, and single-species applications are rare. We developed a novel spatial prioritization model based on accurate estimates of remotely-sensed data and maps of threats potentially affecting long-term species persistence. We used this approach to identify priority areas for the conservation of the Endangered Greek meadow viper Vipera graeca, a cold-adapted species inhabiting mountaintops in the Pindos Mountains of Greece and Albania. We transformed the mapped threats into nine variables to estimate conservation value: habitat suitability (climate suitability, habitat size, occupancy, vegetation suitability), climate change (future persistence, potential for altitudinal range shift) and land-use impact (habitat alteration, degradation, disturbance). We applied the Zonation systematic conservation planning tool with these conservation value variables as biodiversity features to rank the areas currently occupied by the species and to identify priority areas where the chances for population persistence are highest. We found that 90% of current habitats will become unsuitable by the 2080s and that conservation actions need to be implemented to avoid extinction as this is already a threatened species with a narrow ecological niche. If threats are appropriately quantified and translated into variables of conservation value, spatial conservation planning tools can successfully identify priority areas for the conservation of single species. Our study demonstrates that spatial prioritization for single umbrella, flagship or keystone species is a promising approach for the conservation of species for which few data are available.

Here we report on the infection of captive crested geckos Correlophus ciliatus Guichenot (Reptilia: Diplodactylidae), with adults of the ascaridoid nematode, Hexametra angusticaecoides Chabaud & Brygoo, 1960 (Ascarididae). A population of captive crested geckoes became ill and died within a short period of time. Nematodes were recovered from the crested geckoes examined from within the coelomic cavity, penetrating various organs and migrating through subcutaneous tissues, as well as emerging through the geckos' skin. One gecko was treated with levamisole following surgical excision of nematodes from under the skin; this gecko survived. The potential source of the nematode infection in the captive geckoes is discussed. It is most likely that wild-caught Madagascan mossy geckoes, Uroplatus sikorae Boettger (Reptilia: Gekkonidae), introduced the infection to the colony. Molecular sequences of the nematodes are the first produced for the members of this genus. A redescription of the species and its genetic characterization based on the internal transcribed spacer sequence data is provided, suggesting some of the morphological criteria that have been used in the past to distinguish between Hexametra spp. may have been intraspecific morphological variations.

Reliably estimating population parameters for highly secretive or rare animals is challenging. We report on the status of the two largest remaining populations of the Critically Endangered Bermuda skink Plestiodon longirostris, using a robust design capture–mark–recapture analysis. Skinks were tagged with passive integrated transponders on two islands and captured on 15 sampling occasions per year over 3 years. The models provided precise estimates of abundance, capture and survival probabilities and temporary emigration. We estimated skink abundance to be 547 ± SE 63.5 on Southampton Island and 277 ± SE 28.4 on Castle Island. The populations do not appear to be stable and fluctuated at both sites over the 3-year period. Although the populations on these two islands appear viable, the Bermuda skink faces population fluctuations and remains threatened by increasing anthropogenic activities, invasive species and habitat loss. We recommend these two populations for continued monitoring and conservation efforts.

First, I would like to congratulate Wang et al. (2014) for their important work on the dating of the Panxian fauna, a Triassic fossil Lagerstätte that has produced many exquisitely preserved marine reptiles (Motani et al. 2008) and that marks the full recovery of the marine ecosystem (Jiang et al. 2009) following the Permian–Triassic marine mass extinction (PTME). Papers by Wang et al. (2014) and alike are especially welcomed by vertebrate palaeontologists since they provide precise dating results for some of the most important vertebrate fossils in the world, such as the bizarre protorosaur Dinocephalosaurus orientalis (Li, Rieppel & LaBarbera, 2004) and the earliest marine archosaur Qianosuchus mixtus (Li et al. 2006). This related topic is also interesting because of the very recent debate about the timing of recovery from the PTME, the largest biodiversity crash during the Phanerozoic, from the predators’ perspective (Chen & Benton, 2012; Scheyer et al. 2014).

We thank Liu Jun for his comment on our recent paper (Wang et al. 2014) and are grateful for his calling our attention to this apparent contradiction, and we welcome the opportunity to reply. Based on the sensitive high-resolution ion microscope (SHRIMP) U–Pb zircon age for a volcanic tuff bed within the upper part of the Guanling Formation, we suggested in our study that the age of the fossil horizon of the Panxian fauna is 244 ± 1.3 Ma, which is 14 Ma earlier than the previously estimated age that Li, Rieppel & LaBarbera (2004) published in Science. However, Liu Jun argued that this conclusion is confused, that there is no 14 Ma difference and that there is agreement between the biostratigraphic data and the new radiometric age.

Arid Mediterranean regions that shelter unique biodiversity are threatened by increasing anthropogenic pressures, such as urbanization, overgrazing and climate change. In Morocco, one of the main bush species in arid areas, the jujube (Ziziphus lotus), suffers from officially promoted programmes of removal. The Moorish tortoise (Testudo graeca soussensis) is threatened by such habitat loss. Like most animals, the Moorish tortoise must navigate between microhabitats to find essential feeding resources and thermal refuges. This study combined radio-tracking of free-ranging individuals, microhabitat temperature monitoring and transects in a range of habitats. Tortoises were found to depend on the occurrence of large and relatively abundant bushes to escape lethal overheating. Thus, (1) current official encouragements for the destruction of the jujube bushes should be reappraised; (2) habitat restoration relying on replanting jujube bush should be encouraged; and (3) large-scale monitoring of critical bush densities should be used to better organize conservation plans (protection and/or restoration of areas) for the Moorish tortoise.

We investigated the effects of human disturbance and attitudes on the density of the tree agama Acanthocercus atricollis atricollis in a densely populated rural settlement in South Africa. In this environment agamas live on trees that are harvested for firewood or maintained for fruit production. We conducted visual encounter surveys of A. a. atricollis and interviewed local households to establish whether human attitudes and actions could affect tree agama populations. Although local residents viewed tree agamas negatively (50% of interviewees claimed to have killed an agama) and acted to exclude them from their environment, tree agama density in villages was higher than that of adjacent communal rangelands and than a previously reported density estimate in a nearby protected area. We suggest three major factors that could explain why tree agamas are favoured in this peri-urban landscape in the face of human persecution: firstly, predators such as snakes and raptors are likely to occur at a much lower density in peri-urban areas; secondly, their primary prey (insects) may be more abundant or accessible in this landscape; thirdly, they may experience less competition for resources.

Subterranean herpetofauna comprise an estimated 20% of the world's amphibians and reptiles but are one of the least studied groups of terrestrial vertebrates. Monitoring population trends and threats to these species is dependent in part on quantitative historical data, which are generally lacking. One exception is a 1970 study conducted in Ndumu Game Reserve, South Africa. We revisited this area in 2004 and carried out comparative quantitative sampling in deciduous broad-leaf woodland and sand forest habitats. Our results show a 79% reduction in density of subterranean herpetofauna, as well as a reduction in diversity. Mann-Whitney tests show that the amphisbaenian Zygaspis vandami has undergone a significant reduction in density in both habitats sampled. We relate reductions in subterranean herpetofaunal densities to an increased density of the Reserve's ungulate grazers, suggesting a link between reduction in leaf-litter and soil macrofauna prey of the fossorial reptiles. This study highlights the need for quantitative surveys of subterranean herpetofauna to support future conservation efforts.

Enlargement of the forebrain, including elaboration of the thalamus, has occurred independently within different groups of vertebrates. Dorsal and ventral thalamic territories can be identified in most vertebrates, with variations in the presence of GABAergic neuronal components. An inhibitory thalamic reticular nucleus-like input to the dorsal thalamus might be a common feature, as might the organizational plan of two divisions of the dorsal thalamus, the lemnothalamus and collothalamus. Differential, independent elaboration of these divisions occurred in mammals and sauropsids (reptiles and birds), making their evolutionary relationships challenging to discern. Not all of the crucial features identified for mammalian thalamocortical circuitry are present in other vertebrates, but birds share the most features identified to date. These include specific and nonspecific thalamic relay neurons, reciprocal pallial projections, and a GABAergic thalamic reticular nucleus with some but not all hodological features. Because birds share many higher-level cognitive abilities and, thus, possibly higher-level consciousness, with mammals, comparison of the thalamocortical (thalamopallial) circuitry might prove a fruitful resource for testing functional hypotheses. Comparisons with selected other vertebrates that likewise have relatively large brain:body ratios and also exhibit some cognitively sophisticated behaviors, such as cichlid fish, might also prove valuable.