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Visual signals are hitherto assumed to play only a minor role in intra-specific communication in temperate anurans. However, in contrast to most species, males of the Balkan moor frog Rana arvalis wolterstorffi develop a conspicuous dorsal body coloration during the breeding season; its functional significance, however, remains to be clarified. In a first step, we quantified the colour change by measuring the spectral reflection of the eardrum, flank and back of males during immigration and the spawning climax by means of a spectrophotometer between 300 and 700 nm. We found that males change their body colour from dull brown with a more equal reflection spectrum to a bright ultraviolet (UV)-blue with strong reflection between 350 and 450 nm. In contrast, females stay dull brown. A cage experiment revealed no effect of the presence/absence of direct physical contact between females and males on the UV-blue body coloration in males. Moreover, none of the measured colour parameters, that is overall intensity, peak wavelength, UV and blue chroma, were found to correlate with the body condition index of males, indicating that body coloration is not affected by the physical condition of the male. Based on our results and data reported in the literature, we hypothesize that the UV-bluish nuptial coloration, additionally to its assumed function as fitness indicator of the males, may constitute an intra-sexual signal to prevent males from mispairing with other males in high-density mating aggregations. [ABSTRACT FROM AUTHOR]

Several recent studies have demonstrated the occurrence of multiple paternity in anuran amphibians, implying that it is more common than previously thought. However, an adaptive explanation for polyandry in anurans is still lacking. The common toad Bufo bufo is an explosively breeding species that releases its eggs in strings. The operational sex ratio (OSR) is male biased, causing strong scramble competition among males; females can even drown through harassment during multiple amplexi. We used microsatellite markers to determine patterns of paternity in natural B. bufo populations and experimentally mated individuals (females exposed to either two or six males). Thirty per cent of field-collected and 22% of experimentally produced egg strings were sired by at least two males; all others were sired by a single father. Multiple paternities arose only from multiple amplexi, and we found no indication of fertilization from non-amplexing males, for example through free-swimming sperm. Our results suggest that polyandry in B. bufo is likely to occur most often at high population densities, and under the most male-biased OSRs. Moreover, polyandry might be interpreted as being the consequence of females spawning when amplexed by a few males, to avoid the risk of drowning by amplexus with multiple males. [ABSTRACT FROM AUTHOR]

AbstractPond-breeding amphibians are deme-structured organisms with a population genetic structure particularly susceptible to demographic threats. We estimated the effective number of breeding adults (Nb) and the effective population size (Ne) of the European urodele amphibians Triturus cristatus (the crested newt) and T. marmoratus (the marbled newt), using temporal shifts in microsatellite allele frequencies. Eight microsatellite loci isolated from a T. cristatus library were used, five of which proved polymorphic in T. marmoratus, albeit with high frequencies of null alleles at two loci. Three ponds in western France were sampled, situated 4–10 kilometres apart and inhabited by both species. Parent–offspring cohort comparisons were used to measure Nb; samples collected at time intervals of nine or 12 years, respectively, were used to measure Ne. The adult population census size (N) was determined by mark–recapture techniques. With one exception, genetic distances (FST) between temporal samples were lower than among populations. Nb ranged between 10.6 and 101.8 individuals, Ne ranged between 9.6 and 13.4 individuals. For the pond where both parameters were available, Nb/N (overall range: 0.10–0.19) was marginally larger than Ne/N (overall range: 0.09–0.16), which is reflected in the temporal stability of N. In line with the observed differences in reproductive life-histories between the species, Nb/N ratios for newts were about one order of magnitude higher than for the anuran amphibian Bufo bufo. Despite of the colonization of the study area by T. cristatus only some decades ago, no significant genetic bottleneck could be detected. Our findings give rise to concerns about the long-term demographic viability of amphibian populations in situations typical for European landscapes. [ABSTRACT FROM AUTHOR]

Within the anuran amphibians, dendrobatoids (poison-arrow frogs) are renowned for their parental care, but the lack of highly variable DNA markers so far precluded precise and comprehensive measurements of their genetic mating system. Here we present 10 polymorphic microsatellites for Allobates femoralis, a widespread dendrobatoid from the Amazon basin. In 24 field-collected individuals, we found between seven and 15 alleles per locus, without deviations from Hardy-Weinberg equilibrium or linkage disequilibrium. The loci will be employed to quantify reproductive success in view of male territoriality and female mate choice, as well as to determine the fine-scale genetic structure of local populations. [ABSTRACT FROM AUTHOR]

The article discusses the World Congress of Herpetology (WHC) and its accomplishments as an organization. It claims that the association's greatest accomplishment as of December 2010 is the organizing of its first meeting in Canterbury, England in 1989. The meeting has resulted in the creation of the Declining Amphibian Populations Task Force. The WCH was formed in 1982 to advance herpetological research, education and conservation.