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Tuatara are the sole extant species in the reptile order Rhynchocephalia. They are ecologically and evolutionarily unique, having been isolated geographically for ~84 million years and evolutionarily from their closest living relatives for ~250 million years. Here we report the tuatara gut bacterial community for the first time. We sampled the gut microbiota of translocated tuatara at five sanctuaries spanning a latitudinal range of ~1000 km within Aotearoa New Zealand, as well as individuals from the source population on Takapourewa (Stephens Island). This represents a first look at the bacterial community of the order Rhynchocephalia and provides the opportunity to address several key hypotheses, namely that the tuatara gut microbiota: (1) differs from those of other reptile orders; (2) varies among geographic locations but is more similar at sites with more similar temperatures and (3) is shaped by tuatara body condition, parasitism and ambient temperature. We found significant drivers of the microbiota in sampling site, tuatara body condition, parasitism and ambient temperature, suggesting the importance of these factors when considering tuatara conservation. We also derived a 'core' community of shared bacteria across tuatara at many sites, despite their geographic range and isolation. Remarkably, >70% of amplicon sequence variants could not be assigned to known genera, suggesting a largely undescribed gut bacterial community for this ancient host species. [ABSTRACT FROM AUTHOR]

Citizen science and participatory conservation offer benefits to urban wildlife and help foster human–nature relationships in cities. To optimize conservation and social outcomes it is important that initiatives appeal to participants of a wide range of sociodemographic backgrounds. However, this can be challenging when motivation and willingness to undertake activities are influenced by socioecological context. In New Zealand, where control of invasive mammalian predators is a predominant strategy for conservation, trapping of rodents and mustelids has become a popular form of backyard conservation.To understand how the appeal of pest trapping compares with that of other conservation activities, we investigated relationships between sociodemographic characteristics of participants and willingness to undertake three different backyard conservation activities (trapping of pest mammals, monitoring of pest mammals and monitoring of native animals). We also examined barriers and motivations for participating in these activities.Willingness to engage in pest trapping was generally higher than that of the other activities, and although willingness scores for all activities were related to respondents' connection to nature, this relationship was weaker for pest trapping than for monitoring activities. Willingness was also positively related to nature dose for all three activities. Concern for the environment was the only significant motivator of participation for all three activities while social interaction, contributing to community and enhancing one's ego were positively related to willingness for the monitoring activities only.The more general appeal of pest trapping may reflect its more tangible outcomes for conservation or the additional benefits it offers participants through removal of domestic pests.Understanding why some activities appeal across a wide sociodemographic spectrum may allow improved project design that maximizes participant recruitment. By encouraging participation of a wide range of people, such activities could provide an opportunity for people to become more connected with nature. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Successful reproduction is critical to the persistence of at-risk species; however, reproductive characteristics are understudied in many wild species. New Zealand's endemic tuatara (Sphenodon punctatus), the sole surviving member of the reptile order Rhynchocephalia, is restricted to 10% of its historic range. To complement ongoing conservation efforts, we collected and characterized mature sperm from male tuatara for the first time. Semen collected both during mating and from urine after courting contained motile sperm and had the potential for a very high percentage of viable sperm cells (98%). Scanning electron microscopy revealed a filiform sperm cell with distinct divisions: head, midpiece, tail, and reduced end piece. Finally, our initial curvilinear velocity estimates for tuatara sperm are 2–4 times faster than any previously studied reptile. Further work is needed to examine these trends at a larger scale; however, this research provides valuable information regarding reproduction in this basal reptile. [ABSTRACT FROM AUTHOR]

Translocations are an important tool for conserving species at risk of extinction from a range of threats. However, an understanding of the life history of many threatened species prior to translocation is often lacking despite being critical for translocation success. For example, dispersal away from the release site in the years following a translocation—particularly when a protected release site is surrounded by unmanaged habitat—can result in failure to establish a self‐sustaining population; successful translocation practice must therefore include an understanding of a species' dispersal patterns. We examined the postfledging dispersal of 22 juveniles reared from a population of red‐fronted parakeets (Cyanoramphus novaezelandiae), or kākāriki, translocated to a mainland sanctuary in Wellington, New Zealand, 6 years prior. The translocation was one of the first of this species to mainland New Zealand and presented several unknowns, in particular whether a population would establish in a sanctuary bordered both by contiguous forest as well as suburban areas. Juvenile kākāriki were radio‐tracked and their location recorded once a day, 5 days per week, for 6 months or until the transmitter battery was exhausted. Approximately one‐third of radio‐tracked juveniles that dispersed outside the sanctuary were killed by predators. Kākāriki postfledging dispersal beyond the sanctuary was male‐biased, possibly driven by inbreeding avoidance, and distance dispersed decreased with increasing body condition. As species are increasingly being translocated back to mainland New Zealand, information gained in this study helps to fill a fundamental knowledge gap regarding dispersal behavior in a mainland context. [ABSTRACT FROM AUTHOR]

Refuges can be ecologically important, allowing access only to some species or individuals and providing prey protection from predators. Creation of refuges can be used to protect threatened species from introduced predators, which can have large negative impacts that are difficult to attenuate via other means. To design refuges for conservation purposes, refuge accessibility to different species must be understood. Traditional techniques are not adequate to measure or describe complex three‐dimensional spaces which are often important refuges. We designed a novel predictive method for modeling three‐dimensional refuge space using video game software that simulates real‐world physics (Unity, PhysX). We use the study system of endemic New Zealand skinks (Oligosoma spp.), their introduced predators, house mice (Mus musculus), and the habitat of interstitial spaces within rock piles to demonstrate how this modeling technique can be used to inform design of habitat enhancement for conservation. We used video game software to model realistic rock piles and measure their interstitial spaces, and found that the spaces we predicted matched those we measured in real rock piles using computed tomography (CT) scanning. We used information about the sizes of gaps accessible to skinks and mice and the results of our modeling to determine the optimal size of rocks to create refuges which would protect skinks from mice. We determined the ideal rock size to be those with graded diameters of 20–40 mm. The approach we developed could be used to describe interstitial spaces in habitats as they naturally occur, or it could be applied to design habitats to benefit particular species. [ABSTRACT FROM AUTHOR]

Traditional ecological knowledge (TEK) can provide valuable insights into historical abundance, ecology and conservation of species. In this study, we interviewed eight Maori kaumatua of Te Atiawa and Ngāti Kuia to document Maori traditional knowledge, or matauranga Maori, of sooty shearwaters (Puffinus griseus) of the Marlborough Sounds, New Zealand. Interview questions focused on shearwater abundance, breeding habitat, customary harvest, and traditional management. Matauranga Maori suggests high shearwater abundance historically, as well as traditional harvest protocols and traditional population management techniques no longer in use. Government imposed harvest bans reduced interaction with, and thus matauranga Maori of, sooty shearwaters followed by the species experiencing a worldwide decline in abundance and being classified as Near Threatened by the IUCN. Our study serves as an important reminder that TEK and species abundance often decline in tandem and that cultural harvest must be considered when designing conservation management strategies for species. [ABSTRACT FROM AUTHOR]

Indigenous relationships with the environment are embedded in narratives and cultural practices. In New Zealand, Maori have maintained their relationship to the environment through a practical philosophy of environmental guardianship known as kaitiakitanga. Place and practice are inextricably linked in traditional Maori narratives; a connection constructed through Maori creation stories and the concept of whakapapa. However, the speed and scale of urbanisation of Maori communities has changed societal structures and narratives, as well as connections with nature. Urban spaces present new challenges in maintaining processes of connections with the natural world in a kaitiakitanga framework. We explore key components of kaitiakitanga such as place, whakapapa, intergenerational knowledge, resource engagement and spirituality. We discuss why kaitiakitanga should be included as a key value within urban spaces and how kaitiakitanga principles encourage the well-being of people and taiao. The contribution of kaitiakitanga to the urban matrix must also explore the relationships of both mana whenua and mātāwaka. Including indigenous perspectives from both groups when considering urban ecology is a key gap in understanding the impacts of urbanisation on Maori. More importantly, the inclusion of indigenous values such as kaitiakitanga into the urban agenda provides an opportunity to improve environmental outcomes. [ABSTRACT FROM AUTHOR]

The study of amphibian spatial behaviour provides key information for species conservation. Most commonly used techniques to track amphibians are either unsuitable for small species or fail to give sufficiently fine-resolution data of habitat use. We report on the use of non-toxic fluorescent powders to track the fine-scale movement of a threatened New Zealand frog, Leiopelma pakeka. We assess the effect of powder application on frog movements, detection of frog pathways during a dry and a wet period, and the use of this marking technique after a translocation for conservation purposes. Our results show that fluorescent powders can be successfully used to obtain detailed information of fine-scale movements and habitat use of frogs, even during rainy periods. All frogs remained alive throughout the study period and no ill effects were noticeable. This technique has potential use for tracking other species that are too small or cryptic to be tracked using more conventional methods. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms underlying population declines is critical for preventing the extinction of endangered populations. Positive feedbacks can hasten the process of collapse and create an ‘extinction vortex,’ particularly in small, isolated populations. We provide a case study of a male-biased sex ratio creating the conditions for extinction in a natural population of tuatara (Sphenodon punctatus) on North Brother Island in the Cook Strait of New Zealand. We combine data from long term mark-recapture surveys, updated model estimates of hatchling sex ratio, and population viability modeling to measure the impacts of sex ratio skew. Results from the mark-recapture surveys show an increasing decline in the percentage of females in the adult tuatara population. Our monitoring reveals compounding impacts on female fitness through reductions in female body condition, fecundity, and survival as the male-bias in the population has increased. Additionally, we find that current nest temperatures are likely to result in more male than female hatchlings, owing to the pattern of temperature-dependent sex determination in tuatara where males hatch at warmer temperatures. Anthropogenic climate change worsens the situation for this isolated population, as projected temperature increases for New Zealand are expected to further skew the hatchling sex ratio towards males. Population viability models predict that without management intervention or an evolutionary response, the population will ultimately become entirely comprised of males and functionally extinct. Our study demonstrates that sex ratio bias can be an underappreciated threat to population viability, particularly in populations of long-lived organisms that appear numerically stable. [ABSTRACT FROM AUTHOR]

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Reintroduced populations of threatened species are often founded by a small number of individuals, but maximising genetic diversity is often a criterion for founder selection. Reintroduction of pregnant females has been proposed as a means of maximising productivity and genetic diversity, but it is unclear whether the release of pregnant females increases the effective number of founders. Ten male and 20 gravid female egg-laying skinks ( Oligosoma suteri) were reintroduced to Korapuki Island from Green Island, New Zealand in 1992. We sampled the populations on both Green and Korapuki Islands to examine the effect of reintroduction on the genetic structure and fitness of egg-laying skinks following release. The population on Korapuki Island showed multiple genetic signatures of a bottleneck that were not detected in the population on Green Island. At the individual level, juveniles on Korapuki Island were more homozygous than adults on Korapuki and Green Islands. However, we did not find evidence of inbreeding depression using two performance-based surrogates of fitness. Further, the population on Korapuki Island had a significantly larger effective population size than would have been expected by reintroduction of 30 skinks, based on 10,000 simulated populations. The reintroduction of gravid females aided in increasing the effective number of founders, and may be a viable option for maximizing genetic diversity in reintroduced populations, particularly for long-lived species. However, the continued loss of genetic variation in reintroduced populations may have more insidious long-term consequences, such as the loss of adaptive potential, which cannot be assessed in the short-term. [ABSTRACT FROM AUTHOR]

Understanding the impacts of endemic parasites on protected hosts is an essential element of conservation management. However, where manipulative experiments are unethical, causality cannot be inferred from observational correlative studies. Instead, we used an experimental structure to explore temporal associations between body condition of a protected reptile, the tuatara (Sphenodon punctatus) and infestation with ectoparasites (ticks and mites). We surveyed tuatara in a mark-recapture study on Stephens Island (New Zealand), which encompassed the pre-peak, peak and post-peak infestation periods for each ectoparasite. Tick loads during the peak infestation period were negatively related to body condition of tuatara. Body condition before the peak was not related to subsequent infestation rates ; however, tick loads in the peak were negatively related to subsequent changes in body condition. Mite loads during the peak infestation period were not correlated with body condition of tuatara. Body condition before the peak had no effect on subsequent mite infestation rates, but mite loads of small males during the peak were negatively related to subsequent changes in body condition. Our results suggest that both ectoparasites reduce the body condition of tuatara, which has implications for the long-term conservation management of this host and its parasites. [ABSTRACT FROM AUTHOR]

In reptiles, phenotypic measures such as body size usually predict a male's success in territorial interactions. Recent evidence from fish, birds, and mammals has shown that genetic heterozygosity also has a strong influence on competitive ability and territory quality. Here, we provide a comprehensive assessment of the social structure and factors affecting male territory quality and aggressive behavior in a dense population of Tuatara, a long-lived reptile that maintains long-term territories, on Stephens Island, New Zealand. The only significant predictor of female access and competitive ability was male body size, and there was no relationship between male body size or condition and individual genetic heterozygosity. Body size, body condition, and heterozygosity did not predict territory size. Also, heterozygosity, body condition, and territory size had no relationship with the number of females to which a male had access. Large males were more effective at (1) monopolizing areas where females were most dense and (2) guarding females by consistently winning aggressive encounters with other males. Our finding of no relationship between territoriality and heterozygosity probably reflects the genetic background of this large, outbred population or that behavioral attributes or neutral heterozygosity are not appropriate individual fitness correlates for these long-lived reptiles. [ABSTRACT FROM AUTHOR]

Captive breeding is an integral part of many species recovery plans. Knowledge of the genetic mating system is essential for effective management of captive stocks and release groups, and can help to predict patterns of genetic diversity in reintroduced populations. Here we investigate the poorly understood mating system of a threatened, ancient reptile (tuatara) on Little Barrier Island, New Zealand and discuss its impact on the genetic diversity. This biologically significant population was thought to be extinct, due to introduced predators, until 8 adults (4 males, 4 females) were rediscovered in 1991/92. We genotyped these adults and their 121 captively-bred offspring, hatched between 1994 to 2005, at five microsatellite loci. Multiple paternity was found in 18.8% of clutches. Male variance in reproductive success was high with one male dominating mating (77.5% of offspring sired) and one male completely restricted from mating. Little Barrier Island tuatara, although clearly having undergone a demographic bottleneck, are retaining relatively high levels of remnant genetic diversity which may be complemented by the presence of multiple paternity. High variance in reproductive success has decreased the effective size of this population to approximately 4 individuals. Manipulation to equalize founder representation was not successful, and the mating system has thus had a large impact on the genetic diversity of this recovering population. Although population growth has been successful, in the absence of migrants this population is likely at risk of future inbreeding and genetic bottleneck. [ABSTRACT FROM AUTHOR]

Animal life history strategies evolve in response to a range of selective pressures, and often are tightly linked to sensory cues. Squamate reptiles possess well-developed chemosensory systems, which evolved early in their history and remain highly conserved. However, chemosensory abilities are secondarily reduced in primarily visual agamid and chameleonid lizards, which casts doubt on the ubiquity of reliance on chemosensory cues among squamates. Diurnal geckos from New Zealand avoid predators using visual crypsis and are primarily ambush foragers; reliance on visual cues may be a product of strong avian predation pressure and minimal influence from mammals and snakes for the past 80 my. We used New Zealand's diurnal geckos to test the role of local adaptation versus evolutionary conservatism in defining chemosensory systems. Specifically, we tested whether Marlborough green geckos, Naultinus manukanus, use chemoreception to detect and behaviorally respond to (1) food, (2) opposite-sex conspecifics, and (3) native reptilian predators (tuatara, Sphenodon punctatus). Chemosensory cues mediated gecko interactions with all three stimuli tested: (1) the scent of fruit induced greater exploratory behavior, (2) male geckos responded to scent of female conspecifics by increasing lingual sampling and activity, and (3) tuatara fecal cues (but not skin secretions) elicited characteristic antipredator freeze behavior in geckos. Neither the primarily visual life history strategies nor the reduced range of predators of New Zealand's diurnal geckos appears to have reduced their chemosensory abilities relative to other noniguanid squamate reptiles. Instead, our findings support the notion that chemosensory traits remain highly conserved. [ABSTRACT FROM AUTHOR]

Abstract: Tuatara (Sphenodon punctatus) are threatened New Zealand reptiles with temperature-dependent sex determination (TSD). Higher incubation temperatures produce males, and less than 1 °C separates production of males and females. We investigated variability in nesting ecology to assess whether global warming is likely to result in increasingly male-biased populations. We examined nesting seasons during 1998/1999 and 2002/2003 in New Zealand''s largest tuatara population on Stephens Island, and collected hourly temperature recordings and physical descriptions from 70 nests. Nest depths were not significantly different between years, and ranged from 10 to 230 mm from the soil surface to the top egg. Incubation temperatures in successful nests throughout the year-long incubation period ranged from 1.6 to 38.4 °C. Sex ratios of nests were correlated with incubation temperature: 64% males were produced in 1998/1999, a relatively warm season, but we predict an equal sex ratio was produced in 2002/2003. Although temperatures varied over the 2002/2003 season with respect to monthly long-term averages, 2002 was the second warmest year on record. Stephens Island supports a wide range of nesting habitat, a relatively large population of tuatara, and nest characteristics are highly variable. As such, this population is likely to be resilient to global warming in the short term because an equal sex ratio was predicted from a relatively warm season. However, most other islands where tuatara occur are smaller, have smaller populations, and have fewer open areas for nesting and/or shallower soils. These conditions are more likely to produce a male bias in hatchlings because female tuatara do not appear to vary construction of nests with respect to temperature or location. In the extreme, this could lead to the extinction of small populations. [Copyright &y& Elsevier]

Aim We estimated population size, survival, longevity and sex ratio of tuatara (Sphenodon guntheri Buller 1877) on North Brother Island and determined whether recruitment was occurring, to aid management and identify potential problems for population viability. Location This study was conducted on North Brother Island, Cook Strait, New Zealand. This 4-ha island supports the sole remnant population of S. guntheri. Methods Demographic variables were estimated using capture-recapture methods. Tuatara were individually marked and recaptured during twelve trips, spanning a decade. Population size was estimated for selected trips using the CAPTURE package and finite mixture models, and survival was analysed using the Jolly-Seber (J-S) model. Longevity was estimated using tuatara individually marked in 1957. Results Approximately 350 adult tuatara profile likelihood interval (PLI) (294-427) inhabit North Brother Island, and the sex ratio is strongly biased towards males (1.7M: 1F). Annual adult survivorship is high (0.95) for both sexes and some tuatara live for at least 61 years. Main conclusions The small size and biased sex ratio of this population may make it susceptible to demographic stochasticity, Allee effects, and/or loss of genetic variation. Harvesting for translocation could exacerbate such problems. In addition, tuatara have temperature-dependent sex determination (TSD), with males produced at higher incubation temperatures. Global warming may therefore skew the sex ratio further unless female nest site choice or adaptive shifts in pivotal temperatures compensate for rising temperatures. [ABSTRACT FROM AUTHOR]

The article discusses the effective cross-cultural collaborations between universities and indigenous communities. It cites as example of such partnership the collaboration between the Victoria University of Wellington researchers and the Te Atiawa Manawhenua Ki Te Tau Ihu (Te Atiawa) iwi (tribe) in their effort to conserve the tuatara (Sphenodon spp.). The tuatara are the last living representation of the whole order of the ancient reptiles (Rhynchocephalia) that are endemic to Aotearoa (New Zealand).

• 38% of New Zealand's lizard species have historical distributions including cities. • Of the species whose ranges included cities, only 40% are currently found in cities. • For their land area, cities support a disproportionately high number of species. • Many of the species now found in cities have a conservation status of 'at risk'. Cities and urban processes typically have a negative impact on biodiversity via land cover change, high rates of disturbance and high densities of pest species. Increasingly, however, people are being encouraged and empowered to reduce these impacts through urban restoration and backyard conservation initiatives. Internationally, lizards are a common feature of urban biodiversity, but in New Zealand where many species are threatened, little is known about populations of native skinks and geckos in cities. Yet cities may offer unique opportunities for lizard conservation compared with alternatively modified habitats. To explore the potential of cities for the conservation of lizards, we collated knowledge about the current lizard faunas of six New Zealand cities and developed a list of species that would likely have been present in the locations of these cities prior to human settlement. Comparing the two, we found that, although each of the cities has at least one currently urban-dwelling species, the diversity of lizards in all of the cities has declined dramatically since human colonisation. Patterns of species loss in cities reflect those observed across New Zealand more generally; that is, the loss of large-bodied skinks and geckos, probably resulting from predation by introduced mammalian predators, as well as the loss of regionally endemic species. The high diversity of species that are currently, or were historically, present in the locations of New Zealand cities means that urban restoration involving recovery or reintroduction of populations could have significant benefits for lizard conservation and advocacy. [ABSTRACT FROM AUTHOR]

Traditional ecological knowledge (TEK) is a body of knowledge, practice, and belief about the relationships of living beings with one another and their environment. It is gained through observation, handed down through generations by cultural transmission, and can complement scientific knowledge to improve species management. The latter is especially true for abundant species with which indigenous peoples have frequent interactions (e.g., through harvest), but has been studied less frequently in isolated or declining species. We examined Māori TEK of tuatara (Sphenodon spp.) through semi-directed interviews of kaumātua (elders) of Te Atiawa, Ngati Koata, and Ngati Wai iwi, the kaitiaki (guardians) of several islands currently inhabited by tuatara. Tuatara are endemic to Aotearoa, have been declining in numbers since human settlement (c. 800-1000 years ago), and are now restricted to 37 offshore islands. The detail and volume of tuatara TEK was less than that recorded in studies of more abundant or accessible species. In addition, traditional knowledge of the cultural significance of tuatara was more common and detailed among the kaumātua than traditional knowledge of tuatara biology or ecology. The TEK collected, however, provided the first evidence of seven former sites of tuatara occupation, suggested five additional sites that tuatara may currently occupy, contained novel hypotheses for scientific testing, and described tuatara cultural roles that have not been reported previously. We conclude that some Māori TEK of tuatara persists and that this knowledge may serve as a valuable source of ecological information for conservation. [ABSTRACT FROM AUTHOR]

The merit of using genetic markers in ecology is widely acknowledged, but there have been few applications of genetics to the conservation of the endemic New Zealand lizard fauna. Microsatellites are particularly valuable for detecting intraspecific variation and genetic data can be informative for making fine-scale management decisions. Cyclodina whitakeri is listed as "nationally vulnerable, human-induced and conservation dependent" on DOC's threat classification list, and evaluation of intrapopulation diversity and genetic structure is one of the top three research priorities in the DOC recovery plan for the species. Understanding total species diversity is a precursor to this work. We evaluated species-level diversity in C. whitakeri at 12 microsatellite loci and found significant genetic differences between populations. Additionally, data from the captive-bred and wild-caught populations of C. whitakeri provide insight into the management of Whitaker's skinks at Pukerua Bay. [ABSTRACT FROM AUTHOR]

Abstract: We investigated whether the parasite load of an individual could be predicted by its position in a social network. Specifically, we derived social networks in a solitary, territorial reptile (the tuatara, Sphenodon punctatus), with links based on the sharing of space, not necessarily synchronously, in overlapping territories. Tuatara are infected by ectoparasitic ticks (Amblyomma sphenodonti), mites (Neotrombicula spp.) and a blood parasite (Hepatozoon tuatarae) which is transmitted by the tick. We recorded the location of individual tuatara in two study plots twice daily during the mating season (March) in 2years (2006 and 2007) on Stephens Island, New Zealand. We constructed weighted, directed networks to represent pathways for parasite transmission, where nodes represented individual tuatara and edges connecting the nodes represented the extent of territory overlap among each pair of individuals. We considered a network-based hypothesis which predicted that the in-strength of individuals (the sum of edge weights directed towards a node) in the derived network would be positively related to their parasite load. Alternatively, if the derived social network did not reflect actual parasite transmission, we predicted other factors such as host sex, size or territory size may better explain variation in parasite infection patterns. We found clear positive relationships between the in-strength of tuatara and their tick loads, and infection patterns with tick-borne blood parasites. In particular, the extent that individuals were connected to males in the network consistently predicted tick loads of tuatara. However, mite loads of tuatara were significantly related to host sex, body size and territory size, and showed little association with network measures. The results suggest that the pathway of transmission of parasites through a population will depend on the transmission mechanism of the parasite, but that social networks provide a powerful predictive tool for some parasites. [Copyright &y& Elsevier]

Rodents are efficient invaders on a global scale and pose a significant threat to native biotas, particularly in systems such as oceanic islands which support a reduced suite of mammals. Pacific rats (Rattus exulans) are implicated in extinctions, range restrictions and declines of vulnerable endemic faunas throughout the Pacific. However, research into the behavioural and ecological modifications that enable native species to persist in the presence of Pacific rats is scant. We examined the population structure, behaviour and microhabitat use of Duvaucel’s geckos (Hoplodactylus duvaucelii; radio-telemetry), and Pacific rats (spool-and-line tracking) on three New Zealand offshore islands with different histories of rat incursions and eradication: (1) Green Island, historically rat-free, (2) Korapuki, from which rats were eradicated 20 years ago, and (3) Ōhı¯nau, before and 6 months after rat eradication. Although Pacific rats and Duvaucel’s geckos shared habitat at a broad spatial scale, little overlap in micro-habitat use existed where they were sympatric. In the presence of rats, Duvaucel’s gecko capture rates and recruitment were reduced. However, 6 months after rat eradication, and prior to any recruitment, capture rates of adult geckos increased fourfold and geckos were using a greater proportion of habitat preferred by rats. Thus, we provide strong empirical evidence that Pacific rats ecologically displace Duvaucel’s geckos. Highly plastic spatial avoidance behaviour by native prey species in response to the presence of introduced rodents may enable geckos to persist in sympatry with rodents at least in the short-term. [Copyright &y& Elsevier]

Understanding the mechanisms underlying population declines is critical for preventing the extinction of endangered populations. Positive feedbacks can hasten the process of collapse and create an ‘extinction vortex,’ particularly in small, isolated populations. We provide a case study of a male-biased sex ratio creating the conditions for extinction in a natural population of tuatara (Sphenodon punctatus) on North Brother Island in the Cook Strait of New Zealand. We combine data from long term mark-recapture surveys, updated model estimates of hatchling sex ratio, and population viability modeling to measure the impacts of sex ratio skew. Results from the mark-recapture surveys show an increasing decline in the percentage of females in the adult tuatara population. Our monitoring reveals compounding impacts on female fitness through reductions in female body condition, fecundity, and survival as the male-bias in the population has increased. Additionally, we find that current nest temperatures are likely to result in more male than female hatchlings, owing to the pattern of temperature-dependent sex determination in tuatara where males hatch at warmer temperatures. Anthropogenic climate change worsens the situation for this isolated population, as projected temperature increases for New Zealand are expected to further skew the hatchling sex ratio towards males. Population viability models predict that without management intervention or an evolutionary response, the population will ultimately become entirely comprised of males and functionally extinct. Our study demonstrates that sex ratio bias can be an underappreciated threat to population viability, particularly in populations of long-lived organisms that appear numerically stable. [ABSTRACT FROM AUTHOR]

Knowledge gained from monitoring has been the basis for many critical decisions in threatened and endangered species and ecosystem management. Long-term monitoring has been recognized as a necessity for elucidating population trends and community interactions, particularly for long-lived species or ecosystems with slow rates of change. We examine seasonal and annual cycles of morphological changes in a threatened, long-lived, insular reptile, the tuatara (Sphenodon punctatus), on Stephens Island, New Zealand. We used body condition indices as a surrogate measure of fitness, and examined seasonal fluctuations, using data from an intensive mark-recapture study, and long-term trends using a dataset that spans 54 years. In spite of seasonal and annual fluctuations, body condition of tuatara has declined significantly between 1949 and 2003; the decline was only evident after >22 years of monitoring. We hypothesize that increasing numbers of tuatara have resulted in a density-dependent population response driven by past habitat modification on Stephens Island. We emphasize the need for long-term monitoring and suggest that potentially costly management decisions, particularly for long-lived species or ecosystems with slow rates of change, should not be based solely on short-term monitoring. [Copyright &y& Elsevier]

The bacteria of a host's digestive tract play crucial roles in digestion and pathogen resistance. Hosts living in captivity often have more human interaction and antibiotic use, in addition to differences in diet and environment, compared to their wild counterparts. Consequently, wild and captive animals frequently harbour different bacterial communities. We tested whether diversity of diet provided in captivity shifts the gut bacteria of tuatara, an endemic New Zealand reptile, at three captive sites, and examined how the gut community of these tuatara compares to those in the wild. Dietary manipulation did not cause a strong overall shift in tuatara gut bacteria, but individual tuatara did experience bacterial shifts during manipulation, which subsequently reverted after manipulation. We found that Bacteroides, a genus common in most vertebrate guts but rare in tuatara, increased significantly in the gut during manipulation, then decreased post-manipulation. Finally, the gut bacteria of captive tuatara significantly differed from those of wild tuatara, though most of the dominant bacterial genera found in wild tuatara persisted in captive tuatara. This work represents a first investigation of the captive tuatara bacterial community and establishes the sensitivity of the gut community to dietary manipulation and captivity for this relict reptile., (© The Author(s) 2024. Published by Oxford University Press on behalf of FEMS.)

Predicting and preventing outbreaks of infectious disease in endangered wildlife is problematic without an understanding of the biotic and abiotic factors that influence pathogen transmission and the genetic variation of microorganisms within and between these highly modified host communities. We used a common commensal bacterium, Campylobacter spp., in endangered Takahe (Porphyrio hochstetteri) populations to develop a model with which to study pathogen dynamics in isolated wildlife populations connected through ongoing translocations. Takahe are endemic to New Zealand, where their total population is approximately 230 individuals. Takahe were translocated from a single remnant wild population to multiple offshore and mainland reserves. Several fragmented subpopulations are maintained and connected through regular translocations. We tested 118 Takahe from 8 locations for fecal Campylobacter spp. via culture and DNA extraction and used PCR for species assignment. Factors relating to population connectivity and host life history were explored using multivariate analytical methods to determine associations between host variables and bacterial prevalence. The apparent prevalence of Campylobacter spp. in Takahe was 99%, one of the highest reported in avian populations. Variation in prevalence was evident among Campylobacter species identified. C. sp. nova 1 (90%) colonized the majority of Takahe tested. Prevalence of C. jejuni (38%) and C. coli (24%) was different between Takahe subpopulations, and this difference was associated with factors related to population management, captivity, rearing environment, and the presence of agricultural practices in the location in which birds were sampled. Modeling results of Campylobacter spp. in Takahe metapopulations suggest that anthropogenic management of endangered species within altered environments may have unforeseen effects on microbial exposure, carriage, and disease risk. Translocation of wildlife between locations could have unpredictable consequences including the spread of novel microbes between isolated populations., (© 2015 Society for Conservation Biology.)

A wide variety of Salmonella serotypes occurs within reptilian hosts, but their ecology is poorly understood. We collected cloacal swabs from tuatara (Sphenodon punctatus), fairy prions (Pachyptila turtur), and skinks (Oligosoma spp.) on Stephens Island, New Zealand, to screen for Salmonella. Soil samples were also collected from inside burrows of tuatara and fairy prions and tested for Salmonella. We sampled repeatedly from October 2009 to October 2011. Cloacal swabs were collected from 620 tuatara, and no intestinal shedding of Salmonella was detected. Similarly, no Salmonella was detected in fairy prions. In contrast, we isolated Salmonella from 6.5% of skinks and 8.4% of soil samples. We identified two serovars of Salmonella from 52 isolates, Salmonella Saintpaul and Salmonella Mississippi. Salmonella Mississippi was isolated from skinks only and S. Saintpaul was found in skinks and soil samples. Salmonella persists in this ecosystem with skinks as the main wildlife reservoir, and an environmental reservoir exists in the soil from burrows used by skinks, tuatara, and fairy prions. Salmonella was absent from skinks and the soil in winter, raising the question of bacteria persisting through winter.

Studies on interspecific interactions between vertebrates based on thermal benefits are poorly represented in the literature. Ecologists know little about a category of thermoregulation termed kleptothermy. We provide evidence that a close association between a medium-sized reptile (tuatara, Sphenodon punctatus) and a small seabird (fairy prion, Pachyptila turtur) enables the reptile to maintain higher-than-average body temperatures. This is the first multiyear data set to reveal that the presence of an endotherm within a burrow has direct, transferable thermal benefits to an ectotherm. It is possible that such positive interspecific interactions may alleviate thermal stress across the range of a single species. Currently, we know little about the evolutionary consequences of such interactions, and future work should focus on whether these thermal benefits increase fitness through increased growth rates or reproductive output.

We explored infection patterns and temporal dynamics of the protozoan blood parasite Hepatozoon tuatarae (Apicomplexa) infecting the tuatara (Sphenodon punctatus), a protected reptile living on Stephens Island, New Zealand. In March 2006, we surveyed tuatara in five study sites to examine spatial variation in infection prevalence, and four times, from May 2005 to November 2006, we recaptured marked individuals within three study sites to examine the temporal dynamics of infection. We also examined how blood-parasite infection patterns were influenced by host sex, body size, and host infestation with ticks (Amblyomma sphenodonti) and mites (Neotrombicula spp.), which are potential vectors of the blood parasite. Infection prevalence (16.9-24% infected) and intensity (<0.01-0.1% blood cells infected) were low in all samples. Infection intensity varied among the five sampled sites in March 2006, but prevalence did not. Neither infection prevalence nor intensity varied with time, and infections were detected in consecutive samples from recaptured individuals for up to 18 mo. Neither survey showed an influence of host sex on infection, but both surveys showed infection intensity declined with increasing host body size, as did infection prevalence in the spatial survey. In the temporal survey, we found a positive relationship between the tick numbers on hosts and blood-parasite infection intensity, which were stronger in two of the sampling periods and among larger hosts. These data suggest that exposure and susceptibility to infection decreases with host size and that ticks, but not mites, are probably the vectors in this ancient host-parasite association of a long-lived (>50 yr) host.