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    Translocation and post-release monitoring techniques of Auckland green gecko (Naultinus elegans elegans) using a penned release : a thesis in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology, Massey University, Auckland, New Zealand
    (Massey University, 2016) Scott, Sarah Naomi
    A translocation of Auckland green gecko (Naultinus elegans elegans) using penned and hard releases is conducted during an emergency salvage in the Hunua Ranges, Auckland. The value of limiting individuals’ movement post-translocation is discussed. Radio-telometry as a resourceful long-term monitoring technique is also discussed including limitations.. The population of 52 individuals were salvaged prior to deforestation of habitat as part of the mitigation process in human-wildlife conflict. Translocations are a major part of New Zealand’s conservation strategies, and this event proved a unique opportunity to study post-release movements of Auckland green gecko (Naultinus elegans elegans). To test whether penned releases have an effect on post-release movements, salvaged geckos were divided into two groups. One group of individuals was released as a penned release and one group as a non-penned (hard) release. Using radio-telemetry, information was collected on movement behaviours post-release. 100% minimum convex polygons and 95% kernel estimates were used to establish areas for each individual and compared between the two release groups. Due to the small sample sizes, statistical power was low and no statistically significant differences were found between penned and non-penned release groups in terms of movement post-release. However, exploratory data analysis shows some differences in range particularly in relation to distance from release (m). It seems that penned released geckos tend to stay within the area of their release site compared with non-penned released geckos. This could be an early indication of territory and home range establishment from founder individuals. Multiple methods of monitoring post-translocation of green geckos as well as trapping and monitoring or mammalian predators within the area were carried out throughout the duration of the radio-telemetry aspect of the study. The benefits and limitations are discussed for each. Rat trapping in the release site area showed a trend with very low numbers caught (n=2) and high levels of mice prints throughout the general shrubland area. The presence of rat posion in the digestive tract of one rat caught during trapping leans towards successful pest control to date which is keeping numbers of rats at relatively low densities. Using penned release methods during wildlife translocations can prove to be an expensive and long-term endeavour. The practical use of penning Auckland green gecko post-release is still yet to be accurately defined in this study. Using radio tracking techniques to monitor the translocated individuals’ movement behaviours up to 4 weeks after release was successful. Using specific materials and harness designs that are the right ‘fit’ for the species is imperative as was shown with the unsuccessful use of the first design in this study. Transmitters allowed for the collection of detailed information of movement behaviours horizontal and vertical to be collected with ease. For cryptic, arboreal geckos this information would otherwise be difficult to attain if relying only on regular searching techniques such as spotlighting. Future translocations of gecko should consider using radio-telemetry to collect invaluable information for future translocation management decisions.
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    Analysing gecko monitoring data and standardising monitoring procedures at Shakespear, Tawharanui and Whakanewha Regional Parks : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Environmental Management, Massey University, Auckland, New Zealand
    (Massey University, 2015) Chamberlain, Elizabeth
    Constant inventories of New Zealand gecko populations are important to monitor the status of the populations over time and allow diagnosis of declines in abundance. Long-term monitoring can also provide information on how effective different management schemes are for conserving a species. Populations of Pacific geckos (Dactylocnemis pacificus) are monitored at Shakespear and Whakanewha, and populations of forest (Mokopirirakau granulatus) and green geckos (Naultinus elegans) are monitored at Tawharanui and Whakanewha on a yearly basis. Whakanewha has a poison based regime for controlling predators, and Tawharanui and Shakespear are largely reliant on predator-proof fences. Visual encounter surveys (VESs) provide a relative abundance estimate of the gecko populations in terms of catch per unit effort (CPUE). There was no significant change in CPUE over the three years of monitoring (2012-2014) for any of the gecko populations. It is a possibility this could be a result of small statistical power tests. Comparisons of abundance indices could not be made between parks due to the likely difference of detectability in different vegetation types. Despite the change in activity levels of some animal species during different phases of the moon, this study found that the same phenomenon does not occur for green and forest geckos. There was no significant difference in the CPUE of the gecko species from VESs conducted during the new and full moon. Therefore, there is no need to stratify VESs based on the moon phases in order to account for changes in the activity levels of the geckos when obtaining abundance indices. Tracking tunnels have proven an effective monitoring device for estimating the distribution and relative abundance of animal species and have increasingly been used to monitor lizard species. Its use for detecting arboreal geckos has not been completed with any great success. One Pacific gecko was detected in this study using tracking tunnels designed for arboreal geckos, a very low tracking rate. Cell foam retreats (CFRs) were also used for detecting geckos. They were able to detect the presence of all gecko species at the three parks that were detected by VESs except for one instance: CFRs failed to detect the presence of green geckos at Whakanewha. Therefore, it is advisable that they are not used exclusively for monitoring the gecko populations.
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    Conservation biology of the goldstripe gecko (Hoplodactylus chrysosireticus) and interactions with Duvaucel's gecko (Hoplodactylus duvaucelii) on Mana Island, Cook Strait, New Zealand : a thesis presented in partial fulfilment for the degree of Master of Science in Ecology at Massey University
    (Massey University, 2000) Flannagan, Halema Julien
    The conservation biology of goldstripe geckos (Hoplodactylus chrysosireticus) on Mana Island was considered in two ways. First, by studying the ecology, behaviour and population dynamics of H. chrysosireticus on Mana Island and in Taranaki and second, by assessing their behaviour in the presence of newly introduced Duvaucel's geckos (Hoplodactylus duvaucelii) on Mana Island. The activity patterns of H. chrysosireticus were observed at night and during the day on Mana Island between November 1996 and October 1997. H. chrysosireticus were found to exhibit higher levels of diurnal behaviour than previously thought, with over two-thirds of all animals caught during daylight hours (170 out of 257 individuals; mean catch rate = 2.59 per person hour), a behaviour uncharacteristic of the genus. A female-biased sex ratio (0.53:1 male: female) was found among adult H. chrysosireticus on Mana Island but a male bias (1:0.5 male: female) was observed in the Taranaki population. This could be due either to a female-specific behaviour making them more catchable and hence taken more frequently by predators on the mainland, or to the effect of stochastic processes working on a small population. Growth curve estimations showed H. chrysosireticus is slow growing and long-lived, reaching breeding age at around five years. Population size estimates for the main sub-population on Mana Island generated an estimate of 90 (95%C.I 70-136) animals, less than half (200-300) that arising from a survey of the same area in 1993 (200-300) using different survey and calculation methods. Juvenile mortality was high (63% estimate) in the first year and overall population growth slow. The geckos showed high site fidelity with over 90% moving less than 5m from their original point of capture. Population growth on Mana Island is slow despite the absence of mammalian predators, raising serious questions about the security of the remaining mainland populations. Two sets of simultaneous cage and enclosure experiments, designed to observe interactions between H. chrysosireticus and H. duvaucelii were conducted on Mana Island between December 1997 and February 1998. H. chrysosireticus were observed to increase their activity during the day in flax (F2,13 P=0.0040) and climb more in manuka (F2,5 P=0.0450) when in the presence of H. duvaucelii. H. duvaucelii also appear to have preyed upon young H. chrysosireticus when in close contact. The implications of introducing H. duvaucelii to Mana Island and future conservation measures for H. chrysosireticus are discussed.
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    Shelter aggregations, social behaviour, and seasonal plasma corticosterone levels in captive and wild Duvaucel's geckos, Hoplodactylus duvaucelii : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Albany, New Zealand
    (Massey University, 2010) Barry, Manuela
    The development of effective conservation management strategies is reliant on a thorough understanding of the basic biology and life history of the species of concern. New Zealand’s endemic herpetofauna species have undergone severe range contractions since human arrival due to habitat modifications and predation by introduced mammalian pests. Current conservation management practice involves the eradication of such pests as well as the restoration of habitat involving native species reintroductions. Albeit these conservation attempts, detailed information on physiology, ecology and behaviour of most New Zealand’s lizards is scarce, including the Duvaucel’s gecko (Hoplodactylus duvaucelii). In recent years, several H. duvaucelii have been translocated to islands within their historical range as part of restoration projects and in 2006/7 a captive breeding‐for‐release programme has been established. This provided an excellent opportunity to explore some fundamental aspects of H. duvaucelii’s basic physiology and behavioural ecology. I investigated seasonal plasma corticosterone concentrations of captive and wild geckos in relation to several physiological and ecological factors to enhance our understanding of natural fluctuations of seasonal hormone patterns. Such information can aid in evaluating stress related changes in hormone patterns of individuals and populations, which is particularly relevant for the captive management. I compared plasma steroid hormone patterns of captive geckos from a breeding colony with their wild source population over several seasons to assess whether captive lizards suffered from chronic stress, which could compromise their wellbeing and the fitness of future offspring. Further, I explored several aspects of H. duvaucelii’s social behaviour, including diurnal shelter aggregations, scent communication and social interactions using experimental and exploratory studies on captive and wild geckos. The hormone study provided evidence that H. duvaucelii are suitable for captive breeding as they seem to have adapted well to captivity and did not show a chronic elevation of stress hormone levels. Moreover, my research has shown that H. duvaucelii are essentially social lizards that form shelter aggregations year‐round. Adults showed a high tolerance of juveniles in their diurnal shelters and geckos were able to detect and discriminate scents from conspecifics in several social contexts. These social traits as well as the year‐round occurrence of male‐female pairs combined with H. duvaucelii’s life history traits suggest that this species may possess a social system of high complexity. In conclusion, this dissertation provides a foundation for future research and delivers the first insight into the social behaviour and basic endocrinology of this New Zealand endemic lizard.
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    Wellington geckos meet Wairarapa geckos : hybridisation between two genetically and morphologically distinct populations of the New Zealand common gecko complex (Hoplodactylus maculatus) : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Zoology at Massey University, Palmerston North, New Zealand
    (Massey University, 2010) Fitness, Josephine
    The purpose of this study was to use molecular techniques and morphological measurements to set out to find whether a hybrid zone exists between two coastal populations of the common gecko (Hoplodactylus maculatus), on the Wellington south coast. I collected geckos from five sites in a coastal transect from the population of small geckos to the large geckos. Using four genetic loci, one mitochondrial (16S) and three nuclear (Rag-1, Rag-2, C-mos), I was able to determine that the coastal populations do have geneflow, however each population maintains some unique alleles. Morphological evidence reveals a significant difference in gecko sizes from Turakirae Head and those caught at Ocean Beach, separated by just 15 km. Adult geckos at Turakirae Head are on average 10mm smaller (snout-to-vent) than adult geckos at Ocean Beach, representing almost a doubling in average weight. The centre of the steep frequency clines of four characters is coincident and the widths are concordant. The narrower morphological clines indicate stronger selection on the size of the gecko, than on genetic loci.
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    The prevalence of Salmonella and the spatial distribution of its serovars amongst New Zealand's native lizards : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Massey University, Palmerston North, New Zealand
    (Massey University, 2008) Middleton, Danielle Mary Rose Lea
    This thesis considers the prevalence and spatial distribution of Salmonella serovars amongst wild endemic lizards on offshore islands around the coast of New Zealand. The mean test prevalence of faecal excretion of Salmonella was 4.7%. Skinks (Scincidae) were more likely (8.5%) to be carriers of Salmonella than geckos (1.6%). Each island was host to between one and three Salmonella serovars that were not found on any other islands in this study. Two exceptions were Salmonella Bousso and Salmonella Mana which were found on two islands within the same geographical area. Based on the findings of this study, different islands are likely to be hosts to different Salmonella serovars which could have implications for future translocations of native lizards. I also assessed the prevalence and spatial distribution of faecal excretion of Salmonella, Aeromonas and Hafnia alvei within Mana Island. The prevalence of Salmonella on Mana Island was estimated at 5.8%. Salmonella was found predominantly in skinks (10.0%) and less often in geckos (4.1%). H. alvei was found at a prevalence of 1.9%. No Aeromonas species were cultured from any of the cloacal swabs, suggesting that the 95% confidence interval for the true prevalence is 0-3%. Each site sampled in this study was host to one or more unique serovar of Salmonella not found at any of the other sites. The results of this study indicate that Salmonella serovars may become established within populations of lizards and is not spread between them. This may be due to a lack of dispersal of lizards between sites, raising important considerations for the translocation of native lizards. I investigated the prevalence of faecal excretion of Salmonella, H. alvei and Aeromonas by New Zealand native lizards from two captive populations. The mean prevalence of faecal excretion of Salmonella in the captive lizards sampled was 11.5%. There was a higher prevalence of Salmonella within captive population A (22.0%) than in population B (3.6%). No Aeromonas was cultured from any of the lizards. H. alvei was found at a prevalence of 5.2%. The prevalence of Salmonella and H. alvei was significantly higher in captive lizards than in wild populations. Captive lizards may, therefore, not be appropriate founders for new populations of wild lizards. Finally I assessed the different efficiencies of two media and two temperatures in isolating six Salmonella serovars from a reptilian source. All serovars grew equally well at 37°C and 27°C. For most serovars XLD agar was the more successful media than MacConkey agar but the success of different culture media depended on the serovar being cultured. Because lizards are frequently host to a wide range of Salmonella serovars, screening samples using multiple microbiological methods is likely to give the best chance of isolating all Salmonella serovars present.