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Photographic identification of individual animals is a non-invasive and cost-effective method that can provide demographic information on wild populations. This study aims to compare two photo-matching algorithms (Wild-ID and I3S-Spot) using a reintroduced population of pool frogs (Pelophylax lessonae) in the UK as a case study. We compared the following parameters 1) sex and age, 2) image quality, 3) image collection size and 4) processing time to evaluate successful image match rates. There were no significant differences in successful match rates found between sex and age groups. Wild-ID was more sensitive to image quality than I3S-Spot. There was a significant negative relationship between image collection size and successful match rates for I3S-Spot, however, no such relationship for Wild-ID. The findings of our study can be used by conservation practitioners to reduce workload and improve accuracy during population monitoring activities. [ABSTRACT FROM AUTHOR]

Distinguishing between native and introduced species can be difficult, particularly at range borders where patchily distributed populations may occur away from a species' natural core range. The case of native pool frog (Pelophylax lessonae) populations at their northern range limit in Europe is particularly interesting. These are morphologically and genetically distinct populations that are patchily distributed and have been reported from the UK, Sweden and Norway, but up until 2013 were thought to be absent from Finland. When pool frog populations were discovered in south-western Finland they were morphologically classified as belonging to this northern clade. However, the origin of these populations has been unclear and it is possible that the Finnish populations originated through human aided introductions, established themselves recently through natural migration, or are indeed previously undiscovered relic populations. To establish the origin and relationship of these frogs to other populations across Europe we used phylogeographical analysis based on microsatellite and mitochondrial DNA markers. Our results indicate that the Finnish, Norwegian, Swedish, UK, as well as Estonian populations belong to the northern clade. The Finnish frogs are most closely related to Swedish northern pool frogs, but are genetically more diverse. This suggests that the Finnish pool frogs are most likely a relic from postglacial migration, though we could not entirely rule out the possibility of a recent natural or human aided colonisation from Sweden. This has implications for the conservation status of the pool frog in Finland, where it thus far has been considered an invasive alien species. [ABSTRACT FROM AUTHOR]

Study of major histocompatibility complex (MHC) loci has gained great popularity in recent years, partly due to their function in protecting vertebrates from infections. This is of particular interest in amphibians on account of major threats many species face from emergent diseases such as chytridiomycosis. In this study we compare levels of diversity in an expressed MHC class II locus with neutral genetic diversity at microsatellite loci in natterjack toad (Bufo (Epidalea) calamita) populations across the whole of the species’ biogeographical range. Variation at both classes of loci was high in the glacial refugium areas (REF) and much lower in postglacial expansion areas (PGE), especially in range edge populations. Although there was clear evidence that the MHC locus was influenced by positive selection in the past, congruence with the neutral markers suggested that historical demographic events were the main force shaping MHC variation in the PGE area. Both neutral and adaptive genetic variation declined with distance from glacial refugia. Nevertheless, there were also some indications from differential isolation by distance and allele abundance patterns that weak effects of selection have been superimposed on the main drift effect in the PGE zone. [ABSTRACT FROM AUTHOR]

Study of major histocompatibility complex (MHC) loci has gained great popularity in recent years, partly due to their function in protecting vertebrates from infections. This is of particular interest in amphibians on account of major threats many species face from emergent diseases such as chytridiomycosis. In this study we compare levels of diversity in an expressed MHC class II locus with neutral genetic diversity at microsatellite loci in natterjack toad (Bufo (Epidalea) calamita) populations across the whole of the species’ biogeographical range. Variation at both classes of loci was high in the glacial refugium areas (REF) and much lower in postglacial expansion areas (PGE), especially in range edge populations. Although there was clear evidence that the MHC locus was influenced by positive selection in the past, congruence with the neutral markers suggested that historical demographic events were the main force shaping MHC variation in the PGE area. Both neutral and adaptive genetic variation declined with distance from glacial refugia. Nevertheless, there were also some indications from differential isolation by distance and allele abundance patterns that weak effects of selection have been superimposed on the main drift effect in the PGE zone. [ABSTRACT FROM AUTHOR]

Studies the polymerase chain reaction primers for microsatellite loci in the north European water frogs Rana ridibunda and R. lessonae. Population structure and molecular basis; Individual broodstock and progeny; Scientific implications of the study.

Invasive Burmese pythons (Python bivittatus) succumbed to weather-induced mortality in the Florida Everglades in January 2010. We use a mechanistic bioenergetics model to calculate body temperature in various-sized pythons for the successive months of December and January from 2009 to 2014 using daily weather data for the Everglades area. We incorporate python thermal behaviors judged to mitigate weather effects on body temperature. These models suggest that for at least one month in every year except 2013 pythons experienced body temperatures that would subject them to significant physiological stress. However, estimated body temperatures as low as those reported for pythons that succumbed to exposure occurred only in January and December 2010. Results demonstrate the importance of weather variability on survival. [ABSTRACT FROM AUTHOR]