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Background: The morphology of anuran larvae is suggested to differ between species with tadpoles living in standing (lentic) and running (lotic) waters. To explore which character combinations within the general tadpole morphospace are associated with these habitats, we studied categorical and metric larval data of 123 (one third of which from lotic environments) Madagascan anurans. Results: Using univariate and multivariate statistics, we found that certain combinations of fin height, body musculature and eye size prevail either in larvae from lentic or lotic environments. Conclusion: Evidence for adaptation to lotic conditions in larvae of Madagascan anurans is presented. While lentic tadpoles typically show narrow to moderate oral discs, small to medium sized eyes, convex or moderately low fins and non-robust tail muscles, tadpoles from lotic environments typically show moderate to broad oral discs, medium to big sized eyes, low fins and a robust tail muscle. [ABSTRACT FROM AUTHOR]

Studies investigating the contact zones in parapatric species can provide valuable insights into the mechanisms that cause range borders. Such studies can also provide a better understanding of the mechanisms which allow coexistence within contact zones. In land salamanders, parapatric range limits among species are often determined by abiotic factors and interspecific competition. The ranges of the parapatric Salamandra salamandra and S. atra narrowly overlap in the European Alps. Climatic gradients that determine their parapatric range margins suggest dissimilar species-habitat-relationships. However, habitat use for these species has not yet been studied in the contact zone where the parapatric ranges overlap and where the species locally co-occur in syntopy. To better understand their parapatric range limits and local syntopy, we compared the species' microhabitat use in a contact zone in Switzerland and quantified the degree of interspecific niche overlap in relation to resource availability. We observed that most studied microhabitat variables were neither selected nor avoided by the two species, suggesting random use of the habitat for the variables that we studied. Interspecific niche overlap was generally large, but did not differ from that expected by chance. Unlike previous studies that analyzed patterns of cooccurrence of these species at larger spatial scales, we observed no niche differentiation within the contact zone. Both species likely select the same areas that are suitable and available for salamanders while they similarly avoid generally unsuitable habitat. This indicates that niche differentiation can vary depending on the spatial scale where it is investigated. [ABSTRACT FROM AUTHOR]

Habitat loss and environmental pollution are among the main causes responsible for worldwide biodiversity loss. The resulting species and population declines affect all vertebrates including reptiles. Especially in industrialized countries, pollution by agrochemicals is of remarkable importance. Here, habitat loss has historically been associated with expansion of agriculture. Species persisting in such environments do not only need to cope with habitat loss, but more recently, also with chemical intensification, namely pesticide exposure. In this study, we examined effects of different fungicide and herbicide applications on the common wall lizard ( Podarcis muralis ) in grape-growing areas. We used three enzymatic biomarkers (GST, GR, AChE) and for the first time saliva from buccal swabs as a minimal-invasive sampling method for detection. Our results demonstrate absorption of substances by lizards and effects of pesticide exposure on enzymatic activities. Our findings are in accordance with those of previous laboratory studies, although samples were retrieved from natural habitats. We conclude that buccal swabs could become a useful tool for the detection of pesticide exposure in reptiles and have the potential to replace more invasive methods, such as organ extraction or cardiac puncture. This is an important finding, as reptiles are non-target organisms of pesticide applications, and there is a strong need to integrate them into pesticide risk assessments. [ABSTRACT FROM AUTHOR]

Use of glyphosate-based herbicides is increasing worldwide. The authors review the available data related to potential impacts of these herbicides on amphibians and conduct a qualitative meta-analysis. Because little is known about environmental concentrations of glyphosate in amphibian habitats and virtually nothing is known about environmental concentrations of the substances added to the herbicide formulations that mainly contribute to adverse effects, glyphosate levels can only be seen as approximations for contamination with glyphosate-based herbicides. The impact on amphibians depends on the herbicide formulation, with different sensitivity of taxa and life stages. Effects on development of larvae apparently are the most sensitive endpoints to study. As with other contaminants, costressors mainly increase adverse effects. If and how glyphosate-based herbicides and other pesticides contribute to amphibian decline is not answerable yet due to missing data on how natural populations are affected. Amphibian risk assessment can only be conducted case-specifically, with consideration of the particular herbicide formulation. The authors recommend better monitoring of both amphibian populations and contamination of habitats with glyphosate-based herbicides, not just glyphosate, and suggest including amphibians in standardized test batteries to study at least dermal administration. Environ Toxicol Chem 2013;32:1688-1700. © 2013 SETAC [ABSTRACT FROM AUTHOR]

The quality of breeding sites is of great importance for the reproductive success and accordingly the fitness of many animal species. Hence, individuals should decide carefully where to rear their offspring. Often parents have to account for multiple characteristics of habitat quality at once, which in turn might change over time. Specimens confronted with such variability may evolve the ability to display context-dependant decision plasticity. Anuran amphibians breeding in ephemeral pools largely face two risks for their offspring: desiccation and predation. The Neotropical poison frog Ranitomeya variabilis deposits both eggs and tadpoles in phytotelmata. These small tadpole nurseries lower the risk of offspring predation. However, because most poison frog tadpoles are cannibalistic, even these pools need to be surveyed for predators, and parents tend to avoid deposition with conspecifics. We tested if this avoidance behaviour does change in parental R. variabilis depending on seasonal circumstances. Over several months we provided the frogs the option to deposit their eggs or tadpoles in pools that did and did not contain chemical cues of cannibalistic conspecifics, respectively. During the rainy season, frogs strongly avoided conspecific cues for both eggs and tadpoles. Anyway, with the change to the dry season, parental preferences changed such that parent frogs were more likely to deposit tadpoles (but not eggs) in pools containing cues of conspecific tadpoles. We suggest that R. variabilis, a species that typically isolates its cannibalistic offspring, has evolved a plastic feeding behaviour with regard to the risk of phytotelmata desiccation. We interpret that parents provide older tadpoles with younger 'trophic' tadpoles in order to accelerate their development and save them from impending desiccation. [ABSTRACT FROM AUTHOR]

The Brown Tree Snake (Boiga irregularis) is native to Southeast Asia and Australia and has been introduced to Guam. There it causes major ecological and socioeconomic problems and is considered to belong to the 100 worst alien invasive species worldwide. We used a maximum entropy-based Climate Envelope Model to identify worldwide areas outside the species' known range that are potentially suitable under current climatic conditions. Projections revealed that this invasive alien species potentially occurs in tropical and some subtropical regions. In the closer vicinity of the snake's known distribution, highest suitability was found for the Northern Mariana Islands, Hawaiian Islands, Madagascar, New Caledonia, and Fiji Islands. If predictions are interpreted as depicting invasiveness potential of B. irregularis, strategies to prevent invasion should focus on these regions. An analysis of potential distributions under different future anthropogenic climate-change scenarios showed that the Fiji Islands, Hawaiian Islands, and Northern Mariana Islands will remain overall most suitable habitat for the Brown Tree Snake. In addition, we noted an increase of suitability in New Zealand. [ABSTRACT FROM AUTHOR]

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The article presents a study on male harlequin toads (Amphibia: Atelopus hoogmoedi) site fedility, home range and habitat utilization during rainy season at Brownsberg Nature Park, Suriname. It says that field work was conducted in the area, 19 male toads were observed and the dorsal and ventral pattern of specimen was photographed with a Fuji digital camera, and home ranges were examined as fixed kernels. Results show that the relative abundance of male toads was 0.475 per meter, wherein male Atelopus hoogmoedi showed strong site fidelity and the decline of the numbers of captures during the observation indicates little migration or mortality.

The frog Arthroleptides dutoiti Loveridge, 1935, endemic to Mount Elgon, East Africa was last collected in 1962 and has not been observed since. The species is regarded as Critically Endangered by the IUCN Red List and is a priority species on the Zoological Society of London's EDGE (Evolutionarily Distinct, Globally Endangered) project, given its Red List status and phylogenetic distinctiveness. We analyse temporal patterns of abundance (1934–2014) of A. dutoiti and the remainder of the Mount Elgon amphibian assemblage to infer the probability of re-encountering A. dutoiti and assess whether declines are species specific to A. dutoiti, or whether they are assemblage-wide phenomena. Our results show that for localities where surveys have been repeatedly conducted, A. dutoiti is likely to be locally extinct. Declines are observed in other Mount Elgon amphibians, encompassing both specialists and generalists. Causal factors for declines are unknown, but habitat change might be important, given the high degree of forest loss in the area, especially since the turn of the 20th century. Urgent sampling of preferred microhabitats of A. dutoiti at the type locality and surrounding areas beyond those included in our study are required to determine whether or not the species is extinct. Impacts on other taxonomic groups would also be useful to understand so that it can be determined how broad the changes are for the Mount Elgon biota. [ABSTRACT FROM AUTHOR]

Environmental contamination is supposed to be a reason for population declines in reptiles. Especially intensification and expansion of agriculture are leading to increased pesticide exposure risks for wildlife. In the European Union, Special Areas of Conservation (SACs) have been established for the conservation of taxa listed in Annex II of the Habitats Directive. In the SACs, agricultural land use is legal. Therefore, we conducted a risk evaluation of pesticide exposure for Annex II reptiles by calculating proportions of land use with regular pesticide applications within SACs. Using three evaluation factors (occurrence probability, physiology, life-history aspects), a species-specific risk index was created. Nearly half of the species at above-average risk by pesticide use are globally threatened with extinction (IUCN Red List of Threatened Species). About 30% of their SACs are agriculturally used and one priority subspecies of the Habitats Directive is at highest risk ( Vipera ursinii rakosiensis ). Also, all evaluated fresh-water and land-dwelling turtle species are at high risk. National variation in agricultural land use in the SACs was observed. Species at above-average risk are mainly distributed in the Mediterranean and Pannonian/Continental biogeographical regions of Europe. Conservation status according to the IUCN Red List of Threatened Species as well as national differences among the member states argue for the inclusion of pesticide risk assessments in site-specific management plans for SACs to avoid regional loss of reptilian biodiversity. [ABSTRACT FROM AUTHOR]

Environmental contaminants like pesticides concern amphibian conservationists. For many European amphibian species, special areas of conservation were created as they are listed in Annex II of the EU Habitats Directive. Agriculture is not prohibited within these conservation areas. In the present study, a risk evaluation at the European level was conducted to identify proportions of land use with regular pesticide applications within the conservation areas and the specific risk of pesticide exposure depending on the species' biology and ecology. The proportion of agricultural land use and the risk of habitat and individual contamination differ among species but also at national scale. Nearly all species with high risk of habitat pesticide exposure are not threatened within their entire territories and Europe. Conversely, most globally threatened and European priority species are at a lower exposure risk in their habitats - with the exceptionsRana latastei, Pelobates fuscus insubricus, Triturus dobrogicus and Discoglossus jeanneae. In the conservation areas for these species, Habitat Directive management plans need to consider monitoring of habitat contamination with pesticides. Such a monitoring should also be conducted in conservation areas for amphibians that seem to be not threatened yet but are at high exposure risk, e.g. Bombina bombina. Monitoring and conservation action should also take place site-specifically to avoid national or regional loss of amphibian biodiversity. Overall, intensive use of agrochemicals and recent land use changes have the potential to be a serious threat for amphibian species, which can be found within cultivated areas - regardless of their current IUCN status. [ABSTRACT FROM AUTHOR]