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The southernmost population of Eurasian water vole (Arvicola amphibius) inhabited Lake Hula in the upper Jordan Valley until the lake was drained in the 1950s. Considering the continuous conservation and restoration initiatives in the Hula Valley, we set out to verify the extinction of the Hula water vole population using trap surveys, field sign surveys, and owl pellets' content. Having confirmed its recent extirpation, we used museum and archaeological specimens to study the morphological and genetic similarity of the extirpated Hula water voles to both modern conspecifics in Eurasia and to local Pleistocene specimens. Our results suggest that the Hula population represented an admixture of extinct local Pleistocene and extant, probably European, ancestors. The recent anthropogenic extirpation of this unique population could justify its reintroduction. Species distribution modelling, however, suggests future deterioration of habitat suitability over the coming decades. This calls for careful consideration of how sustainable a reintroduction would be. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii causes one of the most frequent parasitic infections in vertebrates on earth. The present study aimed to assess the occurrence of T. gondii infection in cat-hunted wild small mammals, and to determine the circulating T. gondii genotypes in cat prey. There is evidence suggesting that T. gondii may manipulate rodents' behaviour enhancing transmission to their definitive feline host by facilitating predation. Given that most studies focusing on rodent behavior have been performed under laboratory conditions, we tested this hypothesis in the natural environment. We analysed 157 cat-hunted wild small mammals of six different species from Switzerland. Brain and skeletal muscle samples from each animal were tested for T. gondii DNA by PCR, and positive samples were genotyped using a multilocus sequence typing approach, including 10 genetic markers. Additionally, to evaluate exposure to cat faeces, the presence of Taenia taeniaeformis metacestodes was investigated at necropsy. The prevalence of T. gondii in cat-hunted Arvicola amphibius s.l. was 11.1% (7/63), 14.6% (7/48) in Apodemus spp., 13.6% (3/22) in Myodes glareolus, 6.7% (1/15) in Crocidura russula, and 0% in Microtus arvalis (0/8) and Sorex sp. (0/1). All completely genotyped T. gondii parasites, exhibited the ToxoDB #3 genotype, a Type II variant. We additionally analysed 48 trap-captured A. amphibius s.l., which all tested negative for T. gondii infection, contrasting with the higher prevalence in cat-hunted A. amphibius s.l. (0% vs. 11.1%; p = 0.0176). Furthermore, T. taeniaeformis was detected in both groups, indicating widespread contamination with cat faeces in the sampled areas. These results provide evidence that T. gondii infected rodents are at higher risk to be predated by cats and therewith support the behaviour manipulation hypothesis.

Toxoplasma gondii causes one of the most frequent parasitic infections in vertebrates on earth. The present study aimed to assess the occurrence of T. gondii infection in cat-hunted wild small mammals, and to determine the circulating T. gondii genotypes in cat prey. There is evidence suggesting that T. gondii may manipulate rodents' behaviour enhancing transmission to their definitive feline host by facilitating predation. Given that most studies focusing on rodent behavior have been performed under laboratory conditions, we tested this hypothesis in the natural environment. We analysed 157 cat-hunted wild small mammals of six different species from Switzerland. Brain and skeletal muscle samples from each animal were tested for T. gondii DNA by PCR, and positive samples were genotyped using a multilocus sequence typing approach, including 10 genetic markers. Additionally, to evaluate exposure to cat faeces, the presence of Taenia taeniaeformis metacestodes was investigated at necropsy. The prevalence of T. gondii in cat-hunted Arvicola amphibius s.l. was 11.1% (7/63), 14.6% (7/48) in Apodemus spp., 13.6% (3/22) in Myodes glareolus , 6.7% (1/15) in Crocidura russula , and 0% in Microtus arvalis (0/8) and Sorex sp. (0/1). All completely genotyped T. gondii parasites, exhibited the ToxoDB #3 genotype, a Type II variant. We additionally analysed 48 trap-captured A. amphibius s.l. , which all tested negative for T. gondii infection, contrasting with the higher prevalence in cat-hunted A. amphibius s.l. (0% vs. 11.1%; p = 0.0176). Furthermore, T. taeniaeformis was detected in both groups, indicating widespread contamination with cat faeces in the sampled areas. These results provide evidence that T. gondii infected rodents are at higher risk to be predated by cats and therewith support the behaviour manipulation hypothesis. [Display omitted] • High T. gondii infection rates in cat-hunted wild small mammals. • ToxoDB#3 genotype circulating in wild small mammals in Switzerland. • Challenging the behaviour manipulation hypothesis in the natural environment. [ABSTRACT FROM AUTHOR]

Traditional agro‐pastoral practices are more beneficial for biodiversity than intensified agricultural systems. Promotion of the growth of natural herbaceous vegetation in pastoral fields can enhance rodent populations and consequently influence ecological aspects of carnivores with rodent‐based diets, like prey consumption in the European wildcat (Felis silvestris). In this article, we investigated the effects of pastoral field extent, season and prey abundance on wildcat consumption of several prey species in the Cantabrian Mountains (NW Spain). Prey consumption in areas with presence of pastoral fields (even in low proportions) was dominated by profitable field‐dwelling rodent species such as Arvicola monticola. Consumption of Arvicola was not correlated with its abundance and was higher during summer and autumn. Apodemus dominated the wildcat diet in areas with higher forest proportion and far from pastoral fields, particularly during spring. Our results suggest that varying habitat use and seasonal changes in prey accessibility may determine wildcat prey consumption in pastoral landscapes. Our results can contribute to highlight the potential benefits of traditional and sustainable pastoral activities for the conservation of the European wildcat across its distribution range. [ABSTRACT FROM AUTHOR]

The (palaeo)biogeography of water voles is a puzzle that is not solved in detail yet. Extant species of the genus Arvicola cover a vast geographic area of the Palearctic. In this study, we collected morphometric data of extant and fossil Arvicola from Israel at the southern fringe of the water vole distribution area. The dental evolution of water voles is characterised by certain clear trends in the first lower molar (m1) related to crown height, tooth length, the proportion of the anteroconid-complex, and enamel differentiation. Trans-regional correlation of the latter trend shows that it did not develop completely synchronously in all the geographic areas of water voles' distribution, i.e., not at the same evolutionary rate. Based on the size and geographic distribution, we tentatively consider the Israeli material to belong to an A. persicus group, which facilitates the possibility of future taxonomic subdivision. Among the Israeli material, Late Pleistocene remains from Nahal Mahanayeem Outlet (NMO) show a very particular morphology of the first lower molar compared to samples from other localities in Israel and western Asia, which – in our opinion – justifies the establishment of a new species Arvicola nahalensis n. sp. [ABSTRACT FROM AUTHOR]

A total of 116 specimens of the genus Arvicola were collected from western part of Turkey Western part of Anatolia and Turkish Thrace and examined based on geometric morphometrics and traditional morphometrics. Morphometrical analyses showed that A. amphibius populations in western part of Turkey are highly differentiated as Anatolian and Thrace populations. Depend on morphometrical differentiation, we conclude that these two populations, classified within two subspecies; Arvicola amphibius persicus and Arvicola amphibius cerncavskii respectively.

Understanding the driving forces that control vole population dynamics requires identifying bacterial parasites hosted by the voles and describing their dynamics at the community level. To this end, we used high-throughput DNA sequencing to identify bacterial parasites in cyclic populations of montane water voles that exhibited a population outbreak and decline in 2014–2018. An unexpectedly large number of 155 Operational Taxonomic Units (OTUs) representing at least 13 genera in 11 families was detected. Individual bacterial richness was higher during declines, and vole body condition was lower. Richness as estimated by Chao2 at the local population scale did not exhibit clear seasonal or cycle phase-related patterns, but at the vole meta-population scale, exhibited seasonal and phase-related patterns. Moreover, bacterial OTUs that were detected in the low density phase were geographically widespread and detected earlier in the outbreak; some were associated with each other. Our results demonstrate the complexity of bacterial community patterns with regard to host density variations, and indicate that investigations about how parasites interact with host populations must be conducted at several temporal and spatial scales: multiple times per year over multiple years, and at both local and long-distance dispersal scales for the host(s) under consideration. [ABSTRACT FROM AUTHOR]

This study focused on the spirurid nematode Mastophorus muris in water voles (Arvicola amphibius) trapped in three regions in southern Sweden during spring and fall 2013. The collection of water voles formed part of a larger project (EMIRO) on the cestode Echinococcus multilocularis in rodents. The voles' stomach contents were examined for the presence of M. muris. Prevalence, mean abundance and mean intensity of infection were calculated. A generalized linear model model was used to examine the effects of sex, functional group, season and region on the number of M. muris individuals in each vole. Forty-seven of 181 (26%) voles were infected with M. muris , with up to 74 worms each. The overall mean intensity (worms per infected vole) was 15 (95% CI 10–21), and abundance (mean number of worms in all voles) was 4 (95% CI 2–6). Model output indicated a significant effect of season and region with respect to abundance of nematode infection, which was independent of sex and functional group of the investigated host. [ABSTRACT FROM AUTHOR]

Comparison of post-weaning ontogenetic changes in bone structures between phylogenetically close species with different ecology and types of locomotion can provide a broader picture of the role that function can play in growth patterns. Since the skulls of water voles of genus Arvicola exhibit an important morphological variation associated with underground or semi-aquatic habitats, we compare postnatal ontogenetic changes in the mandible of A. sapidus (semi-aquatic) and A. scherman (fossorial). A total of 15 two-dimensional landmarks were digitized on 271 mandibles from collection specimens for geometric morphometric analyses. We compared allometric and phenotypic trajectories, ontogenetic form changes, and estimated bite force between these two taxa. Results revealed that in young individuals of both species, important shape changes occur in the angular and condylar processes. Conversely, the mandible shows significant interspecific differences in size and shape, the orientation of allometric and phenotypic trajectories, and estimated bite force. Across the post-weaning ontogeny, with respect to A. sapidus, A. scherman shows an increased diastema, a lower ramus, a ventral and caudal expansion of the condylar process, and a dorsal expansion of the angular process. Likewise, a comparatively higher estimated bite force was found in A. scherman. All these differences seem to be concomitant with the mechanical stress and functional constraints associated with persistent excavation activity in fossorial water voles. [ABSTRACT FROM AUTHOR]

Abstract The American mink Neovison vison is an invasive carnivore which may significantly affect populations of the water vole Arvicola amphibius. However, its impact on this rodent species depends on the abundance, dispersion and configuration of the habitats suitable for water voles and their accessibility for the mink. Using live-trapping, we studied the water vole and American mink populations inhabiting midfield ponds located in the vicinity of a large lake. In the same area, the mink diet was described after collecting and analysing scats. During four spring seasons, the water vole density gradually increased and no population peaks or crashes were observed. The maximum recorded density was 9.0 individuals/1 km of pond shoreline. Water voles displayed high year-to-year population turnover: less than 5% of the marked individuals were recaptured in the following year. In April–July, the exchange of individuals in the population during one-month periods was also high and usually exceeded 50%. Water vole remains were found in mink scats in all seasons, and the highest overall percentage biomass of water vole in mink diet for a two-months period reached 52.2% in May–June 2012. The results of our study show that at small water bodies adjacent to a large lake, the water vole population may withstand the impact of the invasive American mink. [ABSTRACT FROM AUTHOR]

The incorporation of the spatial heterogeneity of real landscapes into population dynamics remains extremely difficult. We propose combining equation-based modelling (EBM) and agent-based modelling (ABM) to overcome the difficulties classically encountered. ABM facilitates the description of entities that act according to specific rules evolving on various scales. However, a large number of entities may lead to computational difficulties (e.g., for populations of small mammals, such as voles, that can exceed millions of individuals). Here, EBM handles age-structured population growth, and ABM represents the spreading of voles on large scales. Simulations applied to the spreading of a montane water vole population demonstrated that our model is quite efficient in representing the pattern observed and might help to highlight some key parameters during population expansion. This method paves the way for further developments, including the introduction of density-dependent parameters (predation, diseases, etc.) capable of triggering population declines in an explicitly spatial context. [ABSTRACT FROM AUTHOR]

The results of a comparative study conducted on the water vole, steppe lemming, and Campbell hamster, fulfilled by data published on seven other Muridae rodent species, have revealed a positive relation between the extent of sexual dimorphism estimated by the protein level in urine and population numbers typical for each species and the amplitude of its variation. In species with usually low population numbers, the ratio of protein in urine of males to females comprises 0.9; in species with relative stable population numbers, it is 3.4; and, in species with a high amplitude of periodically fluctuating population numbers, it is 8.3. [ABSTRACT FROM AUTHOR]

This study is aimed at analyzing the total mercury in the tissues of mammals adapted to a semiaquatic or subterranean lifestyle and at analyzing the possible role of their antioxidant system in heavy metal detoxication. The water shrew Neomis fodiens Pennant, 1771, European mole Talpa europaea Linnaeus, 1758, muskrat Ondatra zibethicus Linnaeus, 1766, and water vole Arvicola terrestris Linnaeus, 1758 were the species under study. Our results indicate that mercury accumulation in the tissue depends on the age, tissue type, and diet of the species. The highest mercury content was recorded in water shrew tissues compared to other species. Age-dependent accumulation of the toxicant in the animals is reported. A correlation between mercury accumulation and catalase activity in the kidneys of the animals studied was found. [ABSTRACT FROM AUTHOR]

BACKGROUND The beetle Xylotrechus arvicola (Coleoptera: Cerambycidae) is a serious pest of vineyards in the Iberian Peninsula. In previous work, the male beetles, but not females, were shown to produce ( R)-3-hydroxy-2-hexanone, and female beetles were attracted to this compound in a laboratory bioassay. In this study, release rates of 3-hydroxy-2-hexanone from different dispensers were measured in the laboratory, and the attractiveness of these to X. arvicola adults was determined in trapping tests in three traditional wine-growing regions in Spain. RESULTS As a result of laboratory experiments, for field experiments 3-hydroxy-2-hexanone was formulated as 100 μL in a polyethylene sachet (50 mm × 50 mm × 250 µm), and ethanol was formulated as 1 mL in a polyethylene press-seal bag (76 mm × 57 mm ×50 µm). Field catches were similar at all three study sites. Catches in traps baited with 3-hydroxy-2-hexanone alone were not significantly different from those in unbaited control traps, but catches in traps baited with 3-hydroxy-2-hexanone and ethanol in separate sachets, with 3-hydroxy-2-hexanone and ethanol in the same sachet or with ethanol alone were significantly greater than those in control traps. These results confirm that the beetles are attracted to ethanol, and the addition of 3-hydroxy-2-hexanone does not seem to make any difference. CONCLUSIONS Attraction of females for the male-produced compound ( R)-3-hydroxy-2-hexanone has been observed in laboratory but not in field experiments. Traps baited with ethanol are highly attractive to both sexes of adults of X. arvicola, and these can be used for improved monitoring of the adult emergence and for population control by mass trapping. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Xylotrechus arvicola (Olivier) (Coleoptera: Cerambycidae) is an important pest in vineyards ( Vitis vinifera) in the main Iberian wine-producing regions. Larvae were reared with Semi-Synthetic Iglesias (SSI) diet over 27 months and two generations in the laboratory. Larval mortality was highest during the first (49.49 %) and second (9.38 %) month of rearing, increasing to 50.52 % during the first month if F2 reared larvae were obtained from an F1 adult female obtained in laboratory. The diet had sufficient nutrients to enable the pest to complete its life cycle within nine months, with F1 larval viability ranging from 23.49 % to 27.97 % and F2 larval viability reduced to 2.07 %. However, the diet did not allow for the completion of additional life cycles and generations (F3, F4,...). Larval mortality increased as the months of rearing (66.13 %, 69.51 % and 89.50 %) and generations (59.10 % and 76.93 % in F1 and F2, respectively) progressed in the laboratory. The larva-adult period of females obtained in the laboratory was longer than for males. In the laboratory, the life cycle was shortened in relation to the life cycle in the field because larvae did not require a cold period to break diapause and start pupation. This indicates that X. arvicola has the potential to complete its life cycle inside grape wood in vineyards of wine-producing regions with warmer winters. [ABSTRACT FROM AUTHOR]

The montane water vole, Arvicola scherman, can be found at low altitude in northwestern Spain, where it has become a key pest in apple orchards. Its sustainable control entails the knowledge of its reproduction pattern, which is unknown for this region. Thus, we conducted a study on more than 800 voles caught monthly over two years in apple orchards located in Asturias. Sexual characteristics, body measurements and relative age class were recorded. Intra-annual changes in body mass, testicular volume and seminal vesicle length of males did not affect significantly reproduction at a population scale, since pregnant females were detected over the whole year and their occurrence did not show significant intra-annual differences. Consequently, the recruitment of young specimens was also continuous during the study period. Mild temperatures, even in winter, and ample food all the year around presumably meets the demands of physiological cost of continuous reproduction of A. scherman in this area. The implications of our results for facing this vole control in this agroecosystem are discussed. Furthermore, the information here reported might be useful to accurately assess the effect of sustainable control strategies on the reproductive biology of fossorial water voles in this and in similar environments. [ABSTRACT FROM AUTHOR]

In generalist predators the energy needed for reproduction is derived from various prey categories, the profitability of which may vary according to the biomass or accessibility of the prey items. We examined the relationships between the diet and production of young in two Tawny Owl ( Strix aluco) populations in southern Finland. We found a positive correlation between the amount of remnants of different prey in samples of litter collected from the nest bottoms after breeding and the production of young. Three important prey categories in the diet of owls during the nestling period, i.e. Water Voles, Field Voles and thrush-sized birds, seemed to be significantly related to the number of fledglings. However, only thrush-sized birds showed a significant relationship to the number of fledglings when all prey variables were analysed together in one model. The total prey mass was the best predictor of owl brood size. There were no significant local differences between the effects of different prey categories on the production of Tawny Owl young. Our results, combined with some earlier findings, outline the relationship between food supply and the production of Tawny Owl young in southern Finland. With regards to the Tawny Owl this outline can be generalized to other areas with other kinds of food supply within the distribution range of the species. Similar outlines are probably applicable also to many other generalist predators. [ABSTRACT FROM AUTHOR]

Context: Landscape graphs are widely used to model connectivity and to support decision-making in conservation planning. Compartmentalization methods applied to such graphs aim to define clusters of highly interconnected patches. Recent studies show that compartmentalization based on modularity is suitable, but it applies to non-weighted graphs whereas most landscape graphs involve weighted nodes and links. Objectives: We propose to adapt modularity computation to weighted landscape graphs and to validate the relevance of the resulting compartments using demographic or genetic data about the patches. Methods: A weighted adjacency matrix was designed to express potential fluxes, associating patch capacities and inter-patch distances. Eight weighting scenarios were compared. The statistical evaluation of each compartmentalization was based on Wilks' Lambda. These methods were performed on a grassland network where patches are documented by annual densities of water voles in the Jura massif (France). Results: The scenarios in which patch capacity is assigned a small weight led to the more relevant results, giving high modularity values and low Wilks' Lambda values. When considering a fixed number of compartments, we found a significant negative correlation between these two criteria. Comparison showed that compartments are ecologically more valid than graph components. Conclusions: The method proposed is suitable for designing ecologically functional areas from weighted landscape graphs. Maximum modularity values can serve as a guide for setting the parameters of the adjacency matrix. [ABSTRACT FROM AUTHOR]

The wood borer Xylotrechus arvicola has recently become a pest of vineyards in most of the productive winegrowing areas of Spain. The activity of its larvae has important consequences on grapevine production. Different production parameters such as bunch length and weight, number of flowers, wood weight, leaf pigments and Baumé degree of the must were registered in Viura and Tempranillo varieties in La Rioja, separating X. arvicola affected and not affected branches on the individual plants. All the considered parameters were influenced by the wood borer activity, except the Baumé degree. Important differences detected in some of the parameters, indicate that Viura cultivar is more damaged than Tempranillo, despite the fact that the last one shows a higher attack by the borer in the field. Considering the increasing infestation by X. arvicola in Spanish grape production areas, our findings allowed to understand the borer action on the plants and indicated that Tempranillo has a higher tolerance to the attack of this borer, with possible consequences in orienting the choices of varieties for winemaking. [ABSTRACT FROM AUTHOR]

According to ecological theory, the coexistence of competitors in patchy environments may be facilitated by hierarchical spatial segregation along axes of environmental variation, but empirical evidence is limited. Cabrera and water voles show a metapopulation-like structure in Mediterranean farmland, where they are known to segregate along space, habitat, and time axes within habitat patches. Here, we assess whether segregation also occurs among and within landscapes, and how this is influenced by patch-network and matrix composition. We surveyed 75 landscapes, each covering 78 ha, where we mapped all habitat patches potentially suitable for Cabrera and water voles, and the area effectively occupied by each species (extent of occupancy). The relatively large water vole tended to be the sole occupant of landscapes with high habitat amount but relatively low patch density (i.e., with a few large patches), and with a predominantly agricultural matrix, whereas landscapes with high patch density (i.e., many small patches) and low agricultural cover, tended to be occupied exclusively by the small Cabrera vole. The two species tended to co-occur in landscapes with intermediate patch-network and matrix characteristics, though their extents of occurrence were negatively correlated after controlling for environmental effects. In combination with our previous studies on the Cabrera-water vole system, these findings illustrated empirically the occurrence of hierarchical spatial segregation, ranging from within-patches to among-landscapes. Overall, our study suggests that recognizing the hierarchical nature of spatial segregation patterns and their major environmental drivers should enhance our understanding of species coexistence in patchy environments. [ABSTRACT FROM AUTHOR]

We characterized eighteen water voles, Arvicola amphibius (s.l.), from five populations along the Italian peninsula by means of mtDNA cytochrome b (Cytb) sequences. The samples included aquatic voles and one fossorial population from northern Italy. The standard karyotype of four voles from one central Italian population was also analysed and was identical to the one found in other populations outside Italy. Phylogenetic analyses, including vole Cytb haplotypes from the entire range, indicated the existence of a well supported and highly divergent Italian lineage (4.3%), sister to all the other haplotypes. The fossorial voles are not genetically differentiated from the aquatic voles from a nearby population and belong to the same taxon. Given the high Cytb divergence and the results of previous investigations on allozymes and hybrid fertility, we believe that the Italian population of water voles belongs to a distinct species, Arvicola italicus Savi, 1838, with the type locality near Pisa, although a morphological assessment of the entire skull is necessary to define it. [ABSTRACT FROM AUTHOR]

The terminal Pleistocene and Early Holocene, a period from 15 000 to 18 000 Before Present (BP), was critical in establishing the current Holarctic fauna, with temperate-climate species largely replacing cold-adapted ones at midlatitudes. However, the timing and nature of this process remain unclear for many taxa, a point that impacts on current and future management strategies. Here, we use an ancient DNA dataset to test more directly postglacial histories of the water vole (Arvicola amphibius, formerly A. terrestris), a species that is both a conservation priority and a pest in different parts of its range. We specifically examine colonization of Britain, where a complex genetic structure can be observed today. Although we focus on population history at the limits of the species' range, the inclusion of additional European samples allows insights into European postglacial colonization events and provides a molecular perspective on water vole taxonomy. [ABSTRACT FROM AUTHOR]

Xylotrechus arvicola (Coleoptera: Cerambycidae) is a xylophagous species that is becoming an important pest in vineyards in the Iberian Peninsula. The most sensitive stages are adult and egg, but their neonate larvae can also be attacked during the first 24 h after hatching and before entering the wood. Adults were evaluated for seven days against the insecticides spinosad, Beauveria bassiana, imidacloprid and chlorpyrifos and neonate larvae (< 24 h) and eggs of different ages against the described insecticides, as well as flufenoxuron and pyriproxyfen. All insecticides were applied in a Potter tower at a maximum and minimum commercial dose, and showed significant differences both among insecticides as between the applied doses. Most of the hatching occurs eight days after oviposition by X. arvicola females. Chlorpyrifos had a quick and total control of eggs of different ages, neonate larvae and adults in both dosis applied, but its effectiveness could cause serious effects on other non-target species. Pyriproxifen and flufenoxuron had the best ovicidal control when the age of eggs increases and, B. bassiana also had a good ovicidal control, due its capacity to invade the eggs actively through their shell and proliferate inside them. Biological insecticides such as B. bassiana and spinosad, with a total control on adults and good rates of mortality of neonate larvae and eggs can be a great instrument to biological control of this pest. [ABSTRACT FROM AUTHOR]