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Camouflage via animal coloration and patterning is a broadly important antipredator strategy. Behavioral decision making is an influential facet of many camouflage strategies; fitness benefits often are not realized unless an organism selects suitable backgrounds. Controlled experimental studies of behavioral strategies in selection of backgrounds conferring camouflage, however, are rarely paired with observations of wild populations. In order to investigate how substrate composition influenced habitat preference and selection by juvenile desert tortoises (Gopherus agassizii), we completed a manipulative experiment in captivity and an observational study in the wild. In our captive experiment, we found that tortoises spent a greater portion of their time near rocks. We similarly found that wild tortoises preferentially placed themselves in areas with equivalent or larger-sized rocks. Additionally, juvenile tortoises were found to be less detectable on rock substrate by observers than they were on substrate-lacking rocks. We hypothesize that rocks improve juvenile tortoise camouflage and thus that tortoises select for habitat containing rock substrate, in part, due to a survival advantage conferred by such use. The desert tortoise is a threatened species, and the present study provides a model for examining the intersection between behavior and conservation, with implications for how suitable habitat is defined and measured in species conservation programs.

New Zealand's endemic leiopelmatid frogs are all threatened with extinction. There is no obvious physical or behavioural difference between males and females of three of the four species and this lack of a sex identification technique is hindering conservation management. Twenty-one morphological features were measured for 67 live Leiopelma pakeka of known sex to determine whether a slight morphological difference existed that could be used for sex identification. Females were significantly longer in snout-to-vent length (SVL) than males, but as a great deal of overlap exists between sexes, this is not an ideal sex identification trait. No other physical characteristic was significantly different between sexes when adjusted for SVL. Discriminant analysis using a suite of traits was also unable to discriminate between sexes for frogs in the male-female overlap size range. The measurement of physical characteristics is inadequate for identifying sex in L.pakeka and other methods for sex identification must be developed. The reasons for the lack of sexual difference are unknown. [ABSTRACT FROM AUTHOR]

Amidst a global amphibian decline, captive breeding has become an important component of many conservation management programs. Some species fail to readily reproduce in captivity, including leiopelmatid frogs, an archaic lineage endemic to New Zealand. Assisted reproductive technologies can improve the reproductive potential and genetic management of captive programs. Herein we describe efforts to induce spermiation and mating in the threatened Hamilton's frog Leiopelma hamiltoni using a gonadotrophin-releasing hormone agonist and human chorionic gonadotrophin. The spermiation response was poor, with few individuals releasing spermatozoa and a low sperm concentration (mean (±s.e.) 27.4±8.5×103 spermatozoa mL-1 ) when spermiation was stimulated. The sperm concentration peaked 12-24h after hormone administration, suggesting this species may be slower to react than other anurans. Spermic urine was present in five males before hormone treatment. The sperm concentration was higher in this group (128.7±54.9×103 spermatozoa mL-1 ) than in the hormone-induced males. All spermatozoa observed exhibited no motility or, at most, a limited swaying movement with no forward progression. In separate hormone induction trials with 60 individuals (two males to one female per trial), no mating was exhibited during the 12h after treatment. Further studies to hormonally stimulate gamete release and mating are needed in leiopelmatids.

Asynchrony of gamete release is problematic in amphibian captive breeding programs but can be overcome by short-term storage of spermatozoa. Hormonally induced sperm from the model species Anaxyrus fowleri were used to determine storage conditions for optimal fertilisation capacity. Sperm motility was measured over time, as a function of storage temperature (4°C or 22°C) and solution osmolality (7-40mOsm/kg). Sperm at 40mOsm/kg (spermic urine) stored at 4°C exhibited higher motility compared to 22°C. Also, sperm stored at 40mOsm/kg retained higher motility compared to sperm stored below 15mOsm/kg at both temperatures. Under optimal storage conditions (40mOsm and 4°C) a 30% decrease in sperm motility occurred within 24h, however, subsequent loss of sperm motility was lower (<10%/day) for days2-8 thereafter. Sperm samples stored for 1-8days under optimal conditions were tested for fertilising capacity by conducting in vitro fertilisation trials. Sperm stored for 8days yielded 48% neurula development, similar to sperm stored for 1day, which produced 60% neurula development. Overall, sperm stored for up to 8days at 4°C as spermic urine retained fertilising capacity and thus can be used to circumvent asynchronous gamete release in assisted breeding efforts for amphibians.

This study aimed to compare different nonlinear functions to describe the growth curve of European quails and to estimate growth curve parameters, (co)variance components, and genetic and systematic effects that affected the curve using a hierarchical Bayesian model that allows joint estimation. Three different models were fitted in the first stage (Gompertz, Logístic, and von Bertalanffy). The analyzed data set had 45,965 records of 6,838 meat quails selected for higher body weight at 42 d of age for 15 successive generations, weighed at birth, 7, 14, 21, 28, 35, and 42 d of age. Comparisons of the overall goodness of fit were based on deviance information criterion (DIC) and mean square error. Gelfand's check function compared the models at different points of the growth curve. In the second stage, the systematic (sex and generation) and genetic effects were considered in an animal model. Random samples of the a posteriori distributions were obtained by Metropolis-Hastings and Gibbs sampling algorithms. The Gompertz function presented lower DIC and better adjustment at different ages and was defined as the best fit. The heritabilities of A, b, and k parameters were moderate (0.32, 0.29, and 0.18, respectively). The genetics correlations were A and b (0.25), A and k (-0.50), and b and k (0.03). The samples of the posterior marginal distributions for the differences between the estimates of the parameters of the Gompertz model, for generation, A, b, k, age at inflexion point (APOI), and weight at inflexion point (WPOI) showed differences in relation to sex, the females are heavier, A, WPOI, and APOI for females were also higher. In conclusion, 15 generations of selection and changes in the environmental conditions altered the growth curve, leaving the quails heavier and with greater WPOI and APOI, decreased growth rate, and increased the birth weight. The curve parameters could be used in a selection index, despite the difficulty in selecting quails with higher rate of growth and adult body weight., (© 2018 Poultry Science Association Inc.)

The intentional translocation of animals is an important tool for species conservation and ecosystem restoration, but reported success rates are low, particularly for threatened and endangered species. Publication bias further distorts success rates because the results of successful translocations may be more likely to be published than failed translocations. We conducted the first comprehensive review of all published and unpublished translocations of herpetofauna in New Zealand to assess publication bias. Of 74 translocations of 29 species in 25 years, 35 have been reported in the published literature, and the outcomes of 12 have been published. Using a traditional definition of success, publication bias resulted in a gross overestimate of translocation success rates (41.7% and 8.1% for published and all translocations, respectively), but bias against failed translocations was minimal (8.3% and 6.8%, respectively). Publication bias against translocations with uncertain outcomes, the vast majority of projects, was also strong (50.0% and 85.1% for published and all translocations, respectively). Recent translocations were less likely to be published than older translocations. The reasons behind translocations were related to publication. A greater percentage of translocations for conservation and research were published (63.3% and 40.0%, respectively) than translocations for mitigation during land development (10.0%). Translocations conducted in collaboration with a university were more frequently published (82.7% and 24.4%, respectively). To account for some of this publication bias, we reassessed the outcome of each translocation using a standardized definition of success, which takes into consideration the species' life history and the time since release. Our standardized definition of translocation success provided a more accurate summary of success rates and allows for a more rigorous evaluation of the causes of translocation success and failure in large-scale reviews., (© 2014 Society for Conservation Biology.)

Urinary hormone analysis has proved accurate for identifying sex and breeding periods in dimorphic amphibians with known reproductive cycles. We examined whether these techniques could provide this much needed information for a monomorphic anuran with an unconfirmed mating season in the wild. We analysed urinary estrone conjugate, testosterone, and progesterone metabolites to infer the time of breeding and to identify sex in the endangered Maud Island frog, Leiopelma pakeka. Testosterone metabolites in males and estrone and progesterone metabolites in females were at their peak during winter for both wild and captive frogs. These urinary metabolite patterns were consistent with the high proportion of females exhibiting enlarged ovarian follicles in winter months. Sex identification based on urinary estrone metabolite levels was 94% correct in this monomorphic species, in which the sexes overlap in snout-to-vent length (SVL) for over half of their adult size range and in which no other sexually dimorphic trait is known. The seasonal profiles imply unexpected winter or early spring breeding in L. pakeka. Overall, these results demonstrate use of urinary hormone metabolites for reproductive monitoring and sex identification in one of the world's most threatened and evolutionarily distinct amphibians., (Copyright © 2011 Elsevier Inc. All rights reserved.)

With the world currently facing a global amphibian extinction crisis, the development of techniques to help meet the needs of conservation managers and researchers studying the reproductive biology of amphibians is needed. Here, we developed enzyme immunoassays to measure estrone, testosterone, and progesterone hormone metabolites in the urine of Litoria raniformis, the southern bell frog. Concentrations of urinary estrone, testosterone, and progesterone increased during the breeding season for females (P<0.05). Concentrations of urinary testosterone and progesterone increased for males during the breeding season compared with that for months where no reproductive behaviors were observed (P<0.05). Furthermore, urinary estrone concentrations proved to be a reliable sexing tool for adult frogs, with no overlap between the sexes in 98% of cases, regardless of season. There was no difference in estrone (P=0.204) or testosterone (P=0.485) metabolite concentrations between samples taken immediately upon capture and those taken 12 to 24h later from the same individual. Progesterone metabolite concentrations were lower on Day 2 than upon collection (P=0.004). This is the first study to show that urinary hormone analysis can be a useful technique for reproductive monitoring in an amphibian. Additionally, hormone metabolite measures offer promise as sex identification tools for monomorphic species and for those whose secondary sex characteristics are visible only during the breeding season.

Translocations are important tools in the field of conservation. Despite increased use over the last few decades, the appropriateness of translocations for amphibians and reptiles has been debated widely over the past 20 years. To provide a comprehensive evaluation of the suitability of amphibians and reptiles for translocation, we reviewed the results of amphibian and reptile translocation projects published between 1991 and 2006. The success rate of amphibian and reptile translocations reported over this period was twice that reported in an earlier review in 1991. Success and failure rates were independent of the taxonomic class (Amphibia or Reptilia) released. Reptile translocations driven by human-wildlife conflict mitigation had a higher failure rate than those motivated by conservation, and more recent projects of reptile translocations had unknown outcomes. The outcomes of amphibian translocations were significantly related to the number of animals released, with projects releasing over 1000 individuals being most successful. The most common reported causes of translocation failure were homing and migration of introduced individuals out of release sites and poor habitat. The increased success of amphibian and reptile translocations reviewed in this study compared with the 1991 review is encouraging for future conservation projects. Nevertheless, more preparation, monitoring, reporting of results, and experimental testing of techniques and reintroduction questions need to occur to improve translocations of amphibians and reptiles as a whole.