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Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging.

Of the 10,272 currently recognized reptile species, the trade of fewer than 8% are regulated by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the European Wildlife Trade Regulations (EWTR). However, the International Union for Conservation of Nature (IUCN) Red List has assessed 45% of the world's reptile species and determined that at least 1390 species are threatened by “biological resource use”. Of these, 355 species are intentionally targeted by collectors, including 194 non-CITES-listed species. Herein we review the global reptile pet trade, its impacts, and its contribution to the over-harvesting of species and populations, in light of current international law. Findings are based on an examination of relevant professional observations, online sources, and literature (e.g., applicable policies, taxonomy [reptile database], trade statistics [EUROSTAT], and conservation status [IUCN Red List]). Case studies are presented from the following countries and regions: Australia, Central America, China, Galapagos Islands (Ecuador), Germany, Europe, India, Indonesia (Kalimantan), Islamic Republic of Iran, Japan, Madagascar, Mexico, New Zealand, the Philippines, South Africa, Sri Lanka, Vietnam, Western Africa, and Western Asia. The European Union (EU) plays a major role in reptile trade. Between 2004 and 2014 (the period under study), the EU member states officially reported the import of 20,788,747 live reptiles. This review suggests that illegal trade activities involve species regulated under CITES, as well as species that are not CITES-regulated but nationally protected in their country of origin and often openly offered for sale in the EU. Further, these case studies demonstrate that regulations and enforcement in several countries are inadequate to prevent the overexploitation of species and to halt illegal trade activities.

Accurate inventory and monitoring of any faunal group requires field methods that are logistically feasible and ethically acceptable in combination with robust sampling designs. In New Zealand, the development of effective methods for sampling native lizards (currently 99 taxa) required adaptations to techniques used internationally and the invention of novel devices. We summarise and review five standard field methods used for inventory and monitoring of New Zealand lizards (systematic searches, pitfall trapping, funnel trapping, artificial retreats and photo-identification) and acknowledge the influence of the late Tony Whitaker on their development. Tony pioneered the use of baited pitfall traps for capturing terrestrial lizards and binocular-mounted spotlights for locating nocturnal geckos. Recent development of funnel traps, artificial retreats and photo-identification (all used extensively overseas) for New Zealand lizards has resulted in a surge in their uptake here. Arboreal species and lo...

New Zealand has a diverse, endemic skink fauna, which is recognised as the most species rich skink assemblage of any cool temperate region on earth. All native New Zealand skink species are assigned to a single genus, Oligosoma Girard. A new species of Oligosoma is described from screes in montane tussock grassland in the mid-Canterbury high country, New Zealand, where it is currently known from four sites on two mountain ranges. The new species (Oligosoma hoparatea sp. nov.) can be distinguished from all congeners by a combination of mid-body scale row and lamellae counts, scale morphologies, and a bold striped pattern with smooth-edged, dark lateral bands. It is part of the O. longipes Patterson species complex, and occurs in sympatry with its closest relative, O. aff. longipes ‘southern’. The species is currently highly threatened, and is listed as Nationally Critical in New Zealand. Predation by a suite of introduced mammals is assumed to be a major threat to its survival.

The New Zealand lizard fauna is represented by two lineages (Diplodactylidae geckos and Eugongylinae skinks), of which all members are small to medium sized by global standards. Methods used to sample these lizards in the field are a subset of those available worldwide, but include some notable adaptions, novel designs and techniques originally developed for the detection and monitoring of pest mammals. This chapter describes current standard field methods (systematic searching, live trapping and artificial retreats) alongside less frequently used methods (adhesive traps, detector dogs, camera stations and footprint tracking), some of which are still under development or have restricted use. We also discuss the main methods used for individual identification of New Zealand lizards: temporary marking, toe-clipping and photo-identification. When coupled with a thorough understanding of lizard behaviour and ecology, these methods collectively permit effective sampling of the majority of the New Zealand lizard fauna. Arboreal species require further attention, as does the development of accurate, fast and ethically acceptable methods for permanent marking.

The Open Bay Islands are a Māori-owned Wildlife Refuge located in South Westland (South Island) and support two of the rarest lizard species in New Zealand: the Open Bay Island skink and the Open Bay Island gecko. Both species have been assigned a threat status of Nationally Critical – the highest priority for conservation action. The terrestrial and diurnal habits of the skink make it particularly vulnerable to predation by wēkā, a flightless rail native to New Zealand but introduced to the Open Bay Islands c. 100 years ago. Here, we present results from a 5-day survey of the two main islands (14.7-ha Taumaka and 2.2-ha Popotai) and consider options for reducing the negative impacts of wēkā on skinks and other terrestrial fauna (wēkā removal, exclosure fencing and refuge supplementation; all subject to iwi approval). In total, 19 skinks were caught over 125 trap-days. The majority (16 individuals) were caught on Popotai Island, from which skinks had not been previously recorded. We conclude that...

Exotic predators can have detrimental impacts on indigenous fauna. Lethal predator control is commonly used to reduce predator impacts, but is not always feasible, effective or ethical. A promising non-lethal alternative is refuge supplementation for prey. We conducted a Before–After Control–Impact (BACI) experiment over 3 years to determine the relative effects of predator removal (by exclosure fencing) and artificial refuge supplementation on survival of McCann’s skink (Oligosoma maccanni) in duneland on Kaitorete Spit (South Island, New Zealand). Skink populations on 0.0625 ha-grids were randomly assigned to four treatment groups, each replicated four times: (a) predator exclosure only; (b) artificial retreats only; (c) exclosure + artificial retreats, and (d) control (no exclosure or artificial retreats), and monitored annually by pitfall trapping. Capture–recapture analysis was used to estimate the difference in annual survival probability between pre- and post-treatment periods. On average, survival increased only at grids that received the exclosure-only treatment (effect size of 0.03 (0.017–0.043; unconditional 95% CI)). Reduction in predator abundance (by lethal predator control or predator exclusion), but not artificial refuge supplementation, is predicted to benefit McCann’s skink. Our findings add to other studies highlighting the detrimental impacts of exotic predators on indigenous prey and calls for improved means of reducing predator impacts.

Artificial retreats are a low-cost, low-impact and effective technique for detecting cryptic taxa, such as herpetofauna, and have potential as a monitoring tool. The success of using artificial retreats for monitoring is dependent on our ability to maximise detection and minimise variability in sightings within a sampling period. Because ectotherms use retreats for their thermal properties, it may be possible to identify weather conditions during which animals consistently use retreats and design a monitoring protocol based on optimal conditions. We investigated the use of artificial retreats by common skinks, Oligosoma polychroma, in mixed grassland habitat in southern New Zealand under various weather conditions and at a range of times of day. We recorded 1175 sightings of skinks during 1800 artificial retreat checks over a nine day period in early summer 2008. Ambient temperature, rainfall, humidity and time of day were the strongest predictors of skink sightings beneath retreats. Skink sightings were highest and least variable: (1) in an ambient temperature range of 12-18°C, (2) during light or no rain, and (3) at low levels of relative humidity. Under optimal weather conditions, skink counts were similar during the day (8 a.m. to 5 p.m. inclusive) but lower during the evening (8 p.m.). Observer variability, type of substrate beneath the retreat and retreat colour did not significantly influence the number of skinks sighted. We highlight the need to optimise protocols for checking artificial retreats on a species- and site-specific basis before attempting to evaluate their use as a monitoring tool for herpetofauna.

Artificial retreats or refuges (ARs) provide a useful method for sampling lizards and a possible means of restoring habitat to aid population persistence. Previous research suggests that preferences for ARs may vary among species and between different designs. To test these ideas further, we examined the influence of thermal and structural characteristics on use of three types of ARs by the nocturnal common gecko (Hoplodactylus maculatus) and diurnal McCann's skink (Oligosoma maccanni), two lizards endemic to New Zealand. The field study confirmed that the three ARs (triple-layered Onduline, triple-layered iron, solid concrete) differed in retreat-site temperatures provided during each of three seasons (winter, spring and summer). In their top spaces, Onduline ARs were the warmest by day, coolest by night, and thus displayed the largest diel variations in temperature. In the laboratory, common geckos showed a significant preference for Onduline whether ARs were exposed to a radiant overhead heat source or not, whereas skinks did not display any preference among the three types of ARs regardless of heating. The three types of ARs provided field temperatures within the thermal preference range of both species (data obtained from the literature) but only for the top spaces of the ARs and only during summer. Onduline was the only AR to consistently provide the temperatures preferred by pregnant females. Although this study suggests that structural properties alone may be sufficient to explain the preference of geckos for triple-layered Onduline stacks, it does not eliminate the possibility that attractive thermal properties also contribute. Long-term studies are needed to test the effects of artificial refuge supplementation on reptiles, and on their predators and competitors.

The influence of trap placement on capture rate is poorly documented in herpetological studies and requires consideration, because optimizing trap sets can increase detectability of target species and improve capture rates generally. We conducted pitfall trapping for four species of terrestrial lizard in duneland, shrubland and farmland on Kaitorete Spit (South Island, New Zealand). Over 4,800 trap-days, 536 captures of 401 lizards were made. Five microhabitat factors were measured and tested for their ability to influence capture rates of Oligosoma maccanni and Oligosoma nigriplantare polychroma. Generalized linear mixed models revealed that the strongest overall influence on capture rate was the distance separating pitfall traps from the nearest cover (the greater the distance, the lower the capture rate). Weaker, positive influences on capture rate included the amount of vegetation cover surrounding traps and the presence of divaricating shrub and vine species, with some correlations between variables. Capture rates of O. maccanni and O. n. polychroma were highest in duneland and farmland, respectively. Our results show that simple measures such as placing pitfall traps close to cover, will improve capture rates for at least some species of New Zealand endemic skinks. Where such relationships are known in advance, trap placement may be deliberately manipulated to increase capture rates and standardized between sites to improve the validity of using capture rates as indices of relative density. Further research is needed to assess the effect of trap placement for other species and in relation to other factors that influence capture rates.

The survival of New Zealand long‐tailed bats (Chalinolobus tuberculatus) was assessed in two populations, one at Hanging Rock, South Canterbury, South Island, the other at Grand Canyon, central west North Island. Apparent survival of adult females over winter was calculated using mark‐recapture analysis over 5 years. Annual survival varied from 0.75 (95% CI = 0.54–0.88) to 0.89 (0.48–0.99) at Hanging Rock and 0.55 (0.39–0.71) to 0.91 (0.44–0.99) at Grand Canyon. Estimates of apparent survival were consistent with those from a longer‐term study of long‐tailed bats in the Eglinton Valley, Fiordland, South Island. The intrinsic rate of increase (λ) at Hanging Rock was 0.90 (95% CI = 0.4–0.99), indicating that this population may be declining more rapidly than that in the Eglinton Valley. At Grand Canyon, population estimates fluctuated annually, with no clear trend. Predation by introduced mammals and loss of habitat likely caused declines at Hanging Rock. Management of these factors is essential to...

Although the negative effects of close inbreeding in captive populations are well known, inbreeding in small, free-ranging populations is less well understood. During the mid-1980s, small numbers of the flightless Takahe ( Porphyrio hochstetteri ) were successfully translocated from the last remaining population in mountainous Fiordland to four island refuges. Previous research has shown that introduced island Takahe and their descendents lay significantly more infertile eggs and raise fewer juveniles per egg than Takahe in their native habitat in Fiordland. Here we first show that the remnant population of Takahe in Fiordland was likely to have been severely inbred. From this we hypothesize that further, recent inbreeding ( based on four generations of pedigree data ) by Takahe on islands should have negligible fitness consequences. This hypothesis is only partially supported. Mean hatching and fledging success has remained consistently low (

The takahe (Porphyrio hochstetteri) is ahighly endangered flightless rail that isendemic to New Zealand. Only one remnantpopulation of takahe (∼120 adults) is left inthe wild in Fiordland, which has been thesource for introductions to four predator-freeislands. The objective of the present studywas to determine the mating system andamount of genetic variation in takahe usingmultilocus DNA profiling, in order to assist inthe management of the island populations. There was no evidence of extra-pair paternityfor the 27 (73%, n = 37) offspring towhich paternity could be resolved. Thepaternity of the remaining 10 offspring couldnot be resolved due to low levels ofminisatellite DNA variation, but in none wasthe resident male excluded. Overall, the DNAresults along with behavioral and life historyinformation indicate that extra-pairfertilizations should be rare or absent, andtakahe join a small but growing list oflong-lived species of birds that have beenshown to exhibit genetic monogamy. Inaddition, the levels of minisatellite DNAvariation detected in takahe are low relativeto those reported for most other known outbredavian populations, and are consistent with theevidence of the takahe's persistence as asmall, isolated population in Fiordland over atleast the last 100 years. The low geneticvariation is discussed in relation to possibleevidence of environment depended inbreedingdepression in translocated island populationsof takahe.