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Fire retardants are commonly used for fighting wildfires. Retardant chemicals washed via runoff into aquatic systems may be concentrated, thus exposing aquatic species to high levels of ammonium, phosphate, and iron. These chemicals directly affect individual species, which can also cascade to the rest of the aquatic community. We investigated the effects of a prevalent fire retardant, FR CROS 134 (FR), at various concentrations (0 to 11.4 × 102 mg l−1) on larval fire salamander (Salamandra infraimmaculata) and aquatic community structure (bacteria, algae and invertebrates) using mesocosms. We show a negative effect of the presence of FR on the survivorship and time to metamorphosis of salamander larvae (94–17% and 48–64 days, respectively). Moreover, increasing FR concentrations were found to inhibit the predation rate of salamander larvae on mosquito larvae (89–14%). FR decreased the invertebrate community diversity with changes in composition and shifts in evenness and dominance (e.g., cladoceran species abundance increased, whereas calanoid copepod species declined). Finally, cyanobacteria and eukaryotic algal abundance increased, while heterotrophic bacterial abundance decreased with FR addition. The effects of fire retardants on biodiversity found here and the growing use of fire retardants worldwide call for additional evidence-based assessment of their impact, especially in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

The Near Eastern fire salamander (Salamandra infraimmaculata) reaches its southern distribution range in Israel. Although the population structure has been analysed in central Israel and at the southern distribution limit, we lack knowledge on populations in the northern area, such as along Mount Hermon. S. infraimmaculata occurs at Mt. Hermon along an altitudinal gradient and appears to be fragmented by urban and agricultural landscape. We studied the genetic structure of four populations based on microsatellite loci and the mitochondrial D-loop to determine the genetic diversity and connectivity between populations. We observed moderate gene flow at lower parts, i.e. from Tel Dan and Nimrod Castle to Banias indicating extant but limited connectivity. Genetic diversity and gene flow declined along the altitudinal gradient at Mt. Hermon, reaching rock-bottom levels in the highest located population of Nimrod Pool. The observed isolation-by-elevation gradient might induce a higher extinction risk for the highland populations of S. infraimmaculata. [ABSTRACT FROM AUTHOR]

Effective amphibian conservation requires knowledge of both the aquatic and terrestrial phases of life. As extinction probabilities are a function of population size, it is crucial not only to understand the habitat requirement of the species but also to estimate its population size. In this work, we studied the endangered fire salamander, Salamandra infraimmaculata, and analyzed the population size at a total of 14 sites—eight temporary and six permanent. For identifying the local and landscape scales factors predicting S. infraimmaculata's breeding sites we monitored 54 aquatic sites. We found that permanent sites support larger populations of adult salamanders. The breeding site characteristics analyses revealed that at the local scale water depth and shade were the most important factors and two regional variables were found to be important: proximity to another breeding site and elevation. This work provides two clear conservation implications permanent breeding sites will support much larger populations compared to temporary sites, particularly if close to other potential breeding sites, and both terrestrial and aquatic features are important for a site to be suitable for breeding. [ABSTRACT FROM AUTHOR]

Genetic studies on core versus peripheral populations have yielded many patterns. This diversity in genetic patterns may reflect diversity in the meaning of "peripheral populations" as defined by geography, gene flow patterns, historical effects, and ecological conditions. Populations at the lower latitude periphery of a species' range are of particular concern because they may be at increased risk for extinction due to global climate change. In this work we aim to understand the impact of landscape and ecological factors on different geographical types of peripheral populations with respect to levels of genetic diversity and patterns of local population differentiation. We examined three geographical types of peripheral populations of the endangered salamander, Salamandra infraimmaculata, in Northern Israel, in the southernmost periphery of the genus Salamandra, by analyzing the variability in 15 microsatellite loci from 32 sites. Our results showed that: (1) genetic diversity decreases towards the geographical periphery of the species' range; (2) genetic diversity in geographically disjunct peripheral areas is low compared to the core or peripheral populations that are contiguous to the core and most likely affected by a founder effect; (3) ecologically marginal conditions enhance population subdivision. The patterns we found lead to the conclusion that genetic diversity is influenced by a combination of geographical, historical, and ecological factors. These complex patterns should be addressed when prioritizing areas for conservation. [ABSTRACT FROM AUTHOR]

A key environmental factor that varies both spatially and temporally in surface waters is dissolved oxygen (DO). In stagnant ephemeral freshwater ponds, DO can fluctuate diurnally and seasonally, while the constant mixing of water in streams typically maintain DO levels close to saturation with only minor fluctuations. Larvae of the Near Eastern fire salamander (Salamandra infraimmaculata) develop in a range of waterbodies that vary in flow and permanence. To study inter-population variation in larval response to environmental change, we translocated larvae between stream and pond habitats and exposed larvae sampled from different habitat types to hypoxic and normoxic conditions in the laboratory. Larvae transferred from stream to pond retain gill size, while larvae transferred from pond to stream show a reduction in gill size. Larvae that were caged within their native habitat, either stream or pond, display a decrease in gill size similar to larvae transferred from pond to stream. When exposed to experimentally manipulated levels of DO in the laboratory larvae, respectively, increase and decrease gill size under hypoxic and normoxic conditions. Habitat-type origin had a significant effect on the degree of change in gill size with larvae from permanent streams demonstrating the lowest absolute variation in gill size. There was no interaction between DO level (hypoxic/normoxic) and the larvae habitat-type origin. These results suggest that S. infraimmaculata larvae are locally adapted to their aquatic breeding habitat through the plastic ability to respond to the prevailing respiratory conditions by rapidly decreasing or increasing gill size. [ABSTRACT FROM AUTHOR]

Understanding species' distributions often requires taking into consideration the characterization of the environment at different spatial scales. The habitat characteristics of the endangered fire salamander, S. infraimmaculata, have received little attention. In this study, at this species' most peripheral and xeric limit (Mt. Carmel, Israel), we examined predictors of the larval distribution of S. infraimmaculata at aquatic-breeding sites at both local and landscape scales. We investigated the predictive power of environmental variables using two methods: generalized linear models and conditional inference trees (CTREE). Both multi-model approaches yielded similar results. At the local site scale, hydroperiod predicted breeding site use. At the landscape scale, Salamandra presence was best predicted by proximity to other breeding sites. In addition, our study indicates that sites selected for breeding are far from roads and agricultural fields. Overall, this study demonstrates that ultimately, both local and landscape scale predictors are necessary to understand properly a species' habitat requirements and thus can help in planning future management around the breeding sites. [ABSTRACT FROM AUTHOR]

Dispersal may be particularly important for the regional persistence of metapopulations that experience local extinctions. Some amphibian species are structured as metapopulations. Long-term persistence of these species should depend on natural connections between local subpopulations through dispersal. We explored movement distances of fire salamander adults (Salamandra infraimmaculata), a locally endangered species, on Mt. Carmel, northern Israel, and investigated the implications of movement for persistence of populations.During the breeding seasons (November-March) of 1999-2000 and 2002-2006, capture-recapture surveys were conducted around four breeding sites and along unpaved roads connecting them. Out of 300 adult salamander captures, 72 cases were recaptures. Most of the recaptures were in the same site as the initial capture. In eight cases (11%), however, salamanders were recaptured at least 400 m away from the first site. The maximum direct distances between capture-recapture sites (1100-1300 m) were greater than previously documented and indicated potential connectivity between breeding sites.We then examined the potential implications of habitat fragmentation, i.e., isolation of a breeding site, on population persistence by calculating local extinction risks of one of the sites assuming it is an isolated population. Parameters were based on 18 years of count-based data. The high probability of local extinction found by the analysis highlights the severe consequences of fragmentation. Hence, we conclude that it is important to preserve the terrestrial habitats and promote landscape connectivity between breeding sites, in addition to the aquatic sites, in order to enable individual movements between sites and the possibility of a rescue effect. [ABSTRACT FROM AUTHOR]

Many temporary pool invertebrates survive dry periods as diapausing eggs. Theory predicts that the proportion of diapausing eggs that hatch when the pool fills with water should vary with signals of likely reproductive success, if such signals are available. Reproductive success in temporary pool invertebrates is influenced by the presence of predators and desiccation. We studied hatching responses of temporary pool invertebrates to the presence of fire salamanders (Salamandra salamandra L., an important predator in temporary pools), and to manipulations of nutrients. Nutrient manipulations may mimic the increase in conductivity associated with high evaporation and risk of desiccation, but might also affect food availability or modify signals associated with the presence of Salamandra. Fewer eggs of the conchostracan Cyzicus sp. hatched in the presence of Salamandra, and in pools to which nutrients had been added. Other taxa (bdelloid rotifers and chydorids) did not show unambiguous hatching responses to the presence of Salamandra or nutrients. We discuss these results in the light of simple models for optimal hatching fractions. Large crustaceans such as Cyzicus are particularly likely to show strong hatching responses to signals of environmental quality. However, we also expect to find such responses in many other crustaceans. [ABSTRACT FROM AUTHOR]

A number of factors contribute to the process of amphibian decline, among them population fragmentation and road-kills. In this work we evaluated the effects of a road that separates the hibernation area of the Fire Salamander population from their breeding site on the demography and movement behavior. For that we monitored the population for four years using transects along the road and along a river that runs in parallel to the road and serve as the breeding site. We found that the estimated percent of the population killed on the road steadily increased minimally from 2.56 % to 10.78 % over a four year period of increasing vehicular activity. Interestingly, only a small number of individuals were documented on both sides of the road, suggesting there is a potential for population fragmentation due to the road. Additionally, we used geostatistics to reveal that the spatial distribution pattern of the population and road-kills along the road is not random. Thus, conservation efforts that focus on preventing salamanders from accessing the road surface should focus on the areas where the population and road-kills aggregate. [ABSTRACT FROM AUTHOR]