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Avian schistosomes are of medical and veterinary importance as they are responsible for the annually occurring cercarial dermatitis outbreaks. For Austria, so far, only Trichobilharzia szidati Neuhaus 1952 was confirmed on species level as causative agent of cercarial dermatitis. Here we present the first record of Trichobilharzia franki Müller & Kimmig 1994 in Austria. The species was detected during a survey of digenean trematodes in Upper Austrian water bodies. Furthermore, we provide DNA barcodes of T. franki as well as measurements of several parasite individuals to indicate the intraspecific diversity. We also recommend the usage of an alternative primer pair, since the "standard COI primer pair" previously used for Schistosomatidae amplified an aberrant fragment in the sequence of T. franki. Overall, our study shows how limited our knowledge about occurrence and distribution of avian schistosomes in Austria is and how important it is to acquire such a knowledge to estimate ecological and epidemiological risks in the future. [ABSTRACT FROM AUTHOR]

Garra barreimiae (Fowler and Steinitz, Bull Res Counc Isr 5B:262-289, 1956) is a freshwater fish that lives throughout the Hajar Mountains of Oman and the United Arab Emirates. Previously, four different genetic clades (West clade, Central Clade, North clade and East clade) have been identified within this species. This study observes morphological differences between these clades using morphometrics and meristics as well as micro CT imaging, further strengthening the assumption that the taxon of G. barreimiae should be restricted to one of the genetic clades detected. Although many morphometric and meristic characteristics are highly variable within the clades, the West clade fits the original description of G. barreimiae and is distinguishable by its higher number of fifteen to seventeen gill rakers on the lower limb of the first gill arch (compared to the other clades with ten to fourteen gill rakers), its seven branched pelvic fin rays (in contrary to the other clades with eight branched pelvic fin rays) and its number of vertebrae, with typically nineteen precaudal and one intermediate vertebrae, compared to eighteen precaudal and two intermediate vertebrae in the Central and North clade and seventeen precaudal and two intermediate vertebrae in the East clade. [ABSTRACT FROM AUTHOR]

In this study we characterized 10 polymorphic microsatellite markers for the land snail Cylindrus obtusus, an endemism of the Austrian Alps with a distribution in isolated populations above approximately 1,600 m. The microsatellite loci were analyzed in 44 individuals from two populations. Number of alleles per locus ranged between two and eight. Observed heterozygosity ranged between 0.00 and 1.00, and expected heterozygosity between 0.09 and 0.72. No significant linkage disequilibrium was found between pairs of loci. One of the sampled populations (Dachstein) showed no deviation from Hardy–Weinberg equilibrium and no presence of null alleles, whereas the other one (Schneeberg) did. These diverging results probably reflect differences in population structure rather than characteristics of the microsatellite loci and underline the usefulness of these markers for studying genetic diversity, population structure and differentiation in C. obtusus. [ABSTRACT FROM AUTHOR]

Among the 14 extant species of the genus Marmota the Vancouver Island marmot (Marmota vancouverensis) is the most endangered. In 2007 as few as 85 individuals were left in the wild, with an additional 162 individuals maintained in captivity. To facilitate genetic monitoring of both wild and captive populations, polymorphic genetic markers were identified. Thirty-three different microsatellite loci were tested for amplification and variability in ≥30 wild-born individuals. Only 11 of these loci proved to be polymorphic and were subsequently analysed in 105 samples collected from wild Vancouver Island marmots. The average number of alleles (A) at those 11 loci was only 2.1, and the intraspecific variation (HE between 8 and 23% within colonies) was low compared to other marmot species. Variation within the small and geographically isolated Mt. Washington colony was particularly low (A = 1.3, HE = 0.08). Genetic distances between the Mt. Washington colony (11 individuals) and those of the Nanaimo Lakes region (94 individuals) on southern Vancouver Island were large (D values ranging from 0.42 to 0.50), while genetic distances among colonies within the latter area were much smaller (D values from 0.01 to 0.13). Given the low within-population genetic variation, and the resulting risk of inbreeding depression at Mt. Washington, we support the decision to maximize overall genetic variation of the species by crossbreeding marmots from the two different areas despite the possibility of local adaptation. [ABSTRACT FROM AUTHOR]

The small population of brown bears in central Austria originated from a single migrant bear that had settled in the area in 1972 and three bears that were released in the years 1989-1993. Subsequently, the population has been monitored by radio-tracking and collecting data on bear signs and observations. In 2000 we started a genetic monitoring program of the population with the aim to obtain data on population size, sex ratio, relationships as well as movements of individuals. We present results from six years of genetic monitoring, which were combined with field observations. During this time 1,005 hair and faecal samples were gathered in an area of >3,000 km², most of them in the core area of <1,000 km². Furthermore we analysed blood samples from captured individuals. Eight microsatellite and two sex determination loci were employed for DNA profiling. The number of detected individuals is surprisingly low, ranging from 5-8 per year. Concerning relationships the analysis reveals that all genotyped individuals are descendants of the founder individuals indicating that no immigration took place. Only one male and three females (mother and 2 daughters) took part in reproduction. Considering the fact that 28 bears were born in this region since 1991 the question arises where the bears disappear to. Our results suggest that subadult bears migrate from the core area. However, indices of bear occurrence outside the core area are rare and migration could be proved only for two young males. Other explanations, such as increased natural mortality and illegal hunting are discussed. [ABSTRACT FROM AUTHOR]

Knowledge on the mating system of a species is central to understand population dynamics and development. Special attention has been paid to the investigation of monogamous species and evolutionary causes and advantages of this mating system. However, social monogamy does not necessarily imply also genetic monogamy. Given the rarity of genetic monogamy in mammal species and the uncertain conclusions regarding multiple paternity in Eurasian beavers (Castor fiber), here, we undertake a further attempt to clarify the genetic monogamy of Eurasian beavers studying an Austrian beaver population by genotyping of gestating females and their foetuses at 19 microsatellite loci. Microsatellite analysis of mother–offspring groups suggest the occurrence of multiple paternity at a low level: two out of 42 litters (4.8%) were sired by two different males. We discuss the occurrence of extra-pair mating and potential drivers of multiple paternity in the light of beaver biology, population densities, territory characteristics and resulting activity ranges during reproduction period. Especially in the context of increasing beaver population densities in recovering populations and related increase of human-wildlife conflicts, sound knowledge on breeding biology, including species-specific reproduction tactics and their general applicability, is important for population monitoring. [ABSTRACT FROM AUTHOR]