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We report the rediscovery of Microtus bavaricus in Germany, a small mammal that had not been recorded here in more than 60 years. Between 2012 and 2014, a citizen science project addressed cat owners and farmers to collect rodents killed by cats and traps. Until 2017, we conducted 3,432 live trap nights to rediscover the species in and around the area of its discovery. However, only a three-step approach (screening large areas for the occurrence of pine voles using camera trapping, live trapping for collecting genetic material, DNA-barcoding) allowed for the rediscovery of this elusive species near Mittenwald in 2023. [ABSTRACT FROM AUTHOR]

Although cranial bones reliably identify the features of mammals, these traits can be affected by sex, population size and seasonality. This paper biometrically analyses the cranial features of the common vole. The research sample consisted of adult (n = 134), subadult (n = 57), of western Slovakia. Overall, software based on the highlighted marks measured 29 cranial features. Significant sexual dimorphism was observed for three features in adult individuals (width of the maxillary tooth row – right side "WMTRR", maximum height of the mandibula excluding coronoid process "AMdm" and coronoid height of the mandibula "AMd") and four features in subadults (length of the tooth row in the maxilla "LOSD", "WMTRR", length of the molar "LoM" and alveolar length of the lower molars "ALLM"). Results showed a significant positive relationship between body weight and cranial size in 18 of the 29 features. They also suggested a weak but significant positive effect of common vole abundance on cranium size (Chitty effect) likewise in 6 of the 29 features. In several cases, this effect affects, in addition to the abundance, the onset of sexual maturity of individuals. [ABSTRACT FROM AUTHOR]

BACKGROUND: The common vole is an agricultural pest and population outbreaks have caused significant crop damage in the agricultural areas of the west‐central part of the Iberian Peninsula (Spain) during the last few decades. Thus, monitoring is imperative to gain a comprehensive insight on its spatiotemporal habitat colonization dynamics. This work was performed on a long‐term database with the primary objective of establishing an operational framework for understanding the spatial and temporal distribution of the common vole, all of it based on the Getis‐Ord statistics. RESULTS: The temporal evolution of the vole abundance index (VAI) was consistent for the three studied habitats, that is, crops, reservoirs and paths. Furthermore, the majority of common vole abundance peaks coincide with summer periods, especially in annual herbaceous crops. The spatial distribution of vole abundance exhibited a non‐random pattern, characterized by spatial clustering. Particularly, the areas with higher significance of this clustering were located at the so‐called 'Tierra de Campos' county, covering northern Valladolid, southern Palencia and north‐eastern Zamora provinces. Periods of major incidence and concentration were 2013–2014, 2016–2017 and 2019. Common vole temporal occupancy patterns demonstrate that colonization occurred simultaneously in alfalfa reservoirs and dispersion paths, both preceding settlement in annual herbaceous crop plots. CONCLUSION: The geographic information system (GIS)‐hotspots‐based methodology proposed here can be valuable for stakeholders involved in integrated management of the common vole, serving as a detector of pest‐prone areas in both space and time. These hotspots are useful for predicting future surveillance areas that accurately reflect pest colonization patterns. It was found that common vole abundance along dispersal paths acts as a source of dissemination, preceding the risk of colonization in annual herbaceous crop plots. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The common vole has invaded the agroecosystems of northwestern Spain, where outbreaks cause important crop damage and management costs. Little is yet known about the factors causing or modulating vole fluctuations. Here, we used 11 years of vole abundance monitoring data in 40 sites to study density‐dependence and weather influence on vole dynamics. Our objective was to identify the population dynamics structure and determine whether there is direct or delayed density‐dependence. An evaluation of climatic variables followed, to determine whether they influenced vole population peaks. RESULTS: First‐ and second‐order outbreak dynamics were detected at 7 and 33 study sites, respectively, together with second‐order variability in periodicity (2–3 to 4–5‐year cycles). Vole population growth was explained by previous year abundance (mainly numbers in summer and spring) at 21 of the sites (52.5%), by weather variables at 11 sites (27.5%; precipitation or temperature in six and five sites, respectively), and by a combination of previous abundance and weather variables in eight sites (20%). CONCLUSIONS: We detected variability in vole spatiotemporal abundance dynamics, which differs in cyclicity and period. We also found regional variation in the relative importance of previous abundances and weather as factors modulating vole fluctuations. Most vole populations were cyclical, with variable periodicity across the region. Our study is a first step towards the development of predictive modeling, by disclosing relevant factors that might trigger vole outbreaks. It improves decision‐making processes within integrated management dealing with mitigation of the agricultural impacts caused by voles. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

We conducted a habitat suitability assessment for two burrowing rodents, Anatolian or Nehring's blind mole rat (Nannospalax xanthodon) and Harting's vole (Microtus hartingi), on the island of Lesvos using a niche-based approach. We collected data on the presence of the two species across the island and selected several environmental variables, including land cover, geology, and habitat topography, to assess their influence on habitat suitability. We used the Maxent species distribution modelling algorithm to predict suitable habitats. The results showed that both species preferred habitats with low slopes and specific geological substrates, i.e., alluvial deposits and volcanic rocks. M. hartingi showed a preference for open habitats such as saltmarshes and non-irrigated arable land, while N. xanthodon preferred non-irrigated arable land, pastures, and discontinuous urban fabric. The model predicted a wider area of suitable habitats for Microtus hartingi compared to N. xanthodon. Interestingly, the two species are absent from the southeastern part of the island despite our model predicting high suitability; this indicates that a natural barrier of hilly terrain, extensive pine forests, and limestone rock formations may exist that impedes dispersal. Our study provides valuable insights into the habitat preferences of these two burrowing rodents on the island of Lesvos, which can inform biodiversity conservation and ecosystem management strategies. [ABSTRACT FROM AUTHOR]

Here we present, through field collections conducted via monitoring with Sherman traps and phylogenetic analyses of the mitochondrial cytochrome b gene obtained through Sanger sequencing, records worth recognizing of rodent species from Las Joyas Scientific Station (LJSS) within the Sierra de Manantlán Biosphere Reserve. We report for the first time the presence of Nyctomys sumichrasti colimensis in this locality. Additionally, we present new records of Reithrodontomys wagneri and specimens belonging to Reithrodontomys sumichrasti clade IV, a clade recognized as an undescribed species within the R. sumichrasti species complex; the latter expands the geographic distribution of this new species. Finally, we include records of Microtus specimens forming a sister clade with M. mexicanus / M. mogollonensis, albeit with genetic distance values exceeding 9%. Our findings underscore the evolutionary significance of the apparent isolation of Sierra de Manantlán, Jalisco, particularly in influencing the speciation process of various rodent species. These findings underscore the importance of continuing biological inventories in less explored areas of Mexico. [ABSTRACT FROM AUTHOR]

The Caucasian pine vole Microtus daghestanicus was characterized by high karyotypic and molecular genetic variability. However, in the eastern part of the Greater Caucasus, the populations of this species were poorly studied. To reveal the genetic characteristics of these populations and their phylogenetic relationships with other conspecific populations, a sample of Caucasian pine voles from the south of the Chechen Republic (Daikhokh Mount) was analyzed. Immunocytochemical analysis of the synaptonemal complexes at meiotic prophase I showed the belonging of the studied population to the most widespread 54-chromosomal form of M. daghestanicus. Analysis of the complete sequence of the mitochondrial cytochrome b gene showed that on the phylogenetic tree, specimens from the Chechen Republic and the previously studied Caucasian pine vole from North Georgia grouped into one compact cluster. It indicates that they belong to a distinct genetic form. Within the studied sample from the Chechen Republic, variation of the BRCA1 and XIST nuclear genes was revealed that probably reflects complex history of this population associated with alternating events of its isolation from neighboring populations and restoration of contacts between them. [ABSTRACT FROM AUTHOR]

Japanese walnuts (Juglans mandshurica) are known to be seed‐dispersed by the hoarding of two species of rodents, Japanese squirrels (Sciurus lis) and large Japanese field mice (Apodemus speciosus). The previous study showed that the squirrel transported and stored larger walnut seeds farther, whereas the mice transported smaller seeds farther. Divergent selection by different seed dispersers may play an important role in differentiation between local walnut populations, in which understanding seed size heritability is crucial. This study aims to determine how the seed size selected by rodents affects the initial growth of walnuts and to what extent walnut seed size is genetically determined. Sixty walnut seeds were collected from a small seed‐producing tree, and 50 walnut seeds from a large seed‐producing tree were sown and grown for 18 years. The seed size produced from each tree showed that the heritability of seed size was high (h2 = 0.52). When 50 smaller and 50 larger walnut seeds were planted under the same conditions, the dry weight of shoots and roots of the larger seeds was significantly greater than that of the smaller seeds, and root length was also significantly longer in the larger seeds. Seed size is heritable, so if squirrels are inhabiting, larger seeds, which are advantageous for regeneration, will be selected, and walnut trees producing larger seeds will be passed on to the next generation. Because selective hoarding has implications for seed establishment success, inhabiting a suitable seed disperser, the squirrel, is more critical for walnut regeneration than previously assumed. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we investigated differences in the non-fish diet components of the Grey Heron (Ardea cinerea) at both regional and local scales. We found significant inter-regional and inter-colony differences, not only in the diet but also in the habitat composition of foraging areas. We also identified significant relationships between some prey items and different habitats. This study shows that the opportunistic character of the diet of the Grey Heron is adapted to the local foraging habitat and the availability of non-fish prey. Habitat structure on foraging ground is one of the crucial factors determining diet diversity in colonially breeding avian predators. Quantifying the habitat and diet composition at different spatial scales (regional and local inter-colonial) can help provide understanding of the drivers of diet composition. In this study, we examined the composition of the non-fish diet of an opportunistic predator, the Grey Heron (Ardea cinerea), based on pellets. We compared pellets from 21 colonies in two different regions of Poland that differing in composition of foraging habitats. Multivariate statistical techniques were used to analyze the relationship between diet and habitat compositions in a 20 km radius around these colonies. Significant inter-regional and inter-colony differences in Grey Heron diet and habitat composition were detected in foraging areas. However, some prey were present in the diet only from one of the regions. Around the heronries with a predominance of farmland habitats, the European water vole (Arvicola amphibius) and terrestrial invertebrates were present in relatively low frequencies, and the striped field mouse (Apodemus agrarius) was present in high frequencies. Voles (Microtus sp.) were more frequent in colonies with prevalence of non-irrigated arable land around the colony, in contrast to the bank vole (Myodes glareolus), which was less common in heronries with a higher contribution of this habitat type. Remains of aquatic invertebrates were less abundant in colonies surrounded by extensive forests. The results of our research indicate the opportunistic character of the non-fish part of the diet of the Grey Heron adapted to the local foraging habitat and prey availability. [ABSTRACT FROM AUTHOR]

In mammals, hair and skin colour play crucial roles in concealing individuals from predators, facilitating communication within and between species, and contributing to essential physiological functions like thermoregulation. However, certain individuals exhibit abnormal colouration patterns due to either an excess (melanism) or deficiency (albinism, leucism, or piebaldism) in melanin production. Despite the prevalence of chromatic disorders in mammals, instances of species displaying colour anomalies remain infrequent. Here, we report the occurrence of colour anomalies in eight small mammal species (Microtus hartingi, M. dogramacii, M. schidlovskii, M. levis, Mus macedonicus, Sorex sp., Apodemus sp., Nannospalax sp.). In some specimens with colour abnormalities (M. hartingi, M. schidlovskii and M. dogramacii), species identification was confirmed by molecular analysis (cyt b gene region). An individual of M. dogramacii exhibiting colour anomaly was compared with the M. dogramacii species displaying normal colouration through multivariate morphometric analysis and was found to be in the normal range for the species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We investigate the acoustic structure of alarm calls in a highly social rodent, the Harting's vole (Microtus hartingi) and describe the phenomenon of collective shouting of bursts of alarm calls which could be produced in synchronized series. The alarm calls of Harting's voles were recorded using an automatic device from 10 different family groups, containing from 4 to 15 potential callers, released to outdoor enclosures. Natural predators and humans served as call-eliciting stimuli. We reveal acoustic differences between urgent alarm calls, evoked by close-vicinity predators and identified from recordings by their calls and by rustle noise from the caller's escape to burrow, and other alarm calls. We also reveal acoustic parameters between alarm calls produced in bursts and other alarm calls (produced in individual series or by a few non-synchronized callers). We discuss why the alarm calls of Harting's voles are unusually high-frequency (about 17 kHz on average in the maximum fundamental frequency) among other vole species producing high-frequency alarms. Adaptive significance of producing the collective synchronized bursts of alarm calls by Harting's voles remains unclear without direct observations of vocal vigilance in this species under natural conditions. [ABSTRACT FROM AUTHOR]

The relationship between the body condition of different small mammal species and the habitat they occupy is poorly analyzed. We analyzed the body condition index, BCI, of 18 small mammal species trapped in forest, shrub, wetland, meadow, riparian, mixed and fragmented, disturbed, agricultural, and commensal habitats of Lithuania during the span of 1980–2023. The composition of small mammal communities was habitat-dependent, being richest in meadows, with eighteen species, and poorest in riparian habitats, with nine species. A significant variation in the BCI with respect to habitat was observed in eight small mammal species (Sorex araneus, S. minutus, Apodemus agrarius, A. flavicollis, Clethrionomys glareolus, Alexandromys oeconomus, Microtus agrestis, and M. arvalis). The highest average BCI for most of these species was found in disturbed habitats, with S. minutus and M. arvalis showing the highest BCI in agricultural habitats. The lowest average BCI for most species was found in mixed habitats, while C. glareolus and M. arvalis exhibited the lowest BCI in shrub habitats. In general, species dominating certain habitats did not have the highest BCI. This is the first multi-species, multi-habitat study of body condition in small mammals at mid-latitudes. [ABSTRACT FROM AUTHOR]

Current grassland restoration strategies aim to recreate grassland vegetation communities, and often rely on high‐diversity native seeding to promote vegetation diversity. Questions remain concerning the influence of vegetation richness and diversity on grassland fauna. Small‐mammal communities are integral parts of grassland ecosystems, but their responses to restoration are often mixed or overlooked. During July 2014 to 2016, we used Sherman live traps to survey grassland small‐mammal communities of 24 study sites in northeastern South Dakota and southeastern North Dakota, USA, to better understand their responses to vegetation cover type, diversity, richness, and site‐specific vegetation structure. Sites represented a vegetation species richness gradient and 3 vegetation cover types including low‐diversity restorations planted with dense nesting cover (DNC) seed mix, high‐diversity seeded restorations, and unseeded reference grasslands. Small‐mammal abundance was highest at low‐diversity DNC restoration sites and lowest in reference grassland. Small‐mammal diversity was highest at high‐diversity restoration sites and lowest at low‐diversity DNC restoration sites. Models assessing the influence of vegetation structure on the abundance of focal taxa differed. Deer mice (Peromyscus spp.) were negatively influenced by percent native vegetation cover, and voles (Microtus spp.) showed yearly variation and were influenced positively by litter depth and negatively by vegetation richness. Small‐mammal communities of low‐diversity DNC restorations differed from reference sites, but high‐diversity restorations were not different from reference or low‐diversity DNC sites. Thirteen‐lined ground squirrel (Ictidomys tridecemlineatus) abundance was higher at reference and high‐diversity restored sites, while low‐diversity DNC sites had higher deer mice abundance. Results indicate small mammals are unlikely to respond uniformly to vegetation characteristics, and diversity of seed mixes used in grassland restoration is likely to influence grassland small‐mammal communities. [ABSTRACT FROM AUTHOR]

Habitat loss and change are often implicated as the primary causes of species extinction. Although any population can be instantly imperiled by catastrophe, most habitat loss occurs gradually, thus enabling affected individuals an adaptive advantage to occupy the best of their dwindling opportunities. I demonstrate how to infer the advantage between two habitats for any density and frequency‐dependent strategy of habitat selection. I explore the concept of an Adaptive Dispersal Strategy Landscape to reveal the Evolutionarily Stable Strategy separately for ideal‐free and ideal preemptive habitat selectors. Both solutions reveal an initially counterintuitive expectation that individuals living at high density gain insufficient adaptive advantage to disperse from a deteriorating habitat. Adaptive dispersal is constrained at high density because habitats of better quality are fully occupied. I test the theory with measures of movement and foraging in crossover experiments on a seminatural population of meadow voles. The experiment allowed the voles to choose among patches and between enclosures in which I differentially manipulated food and shelter. Although photographs from an infrared camera documented voles venturing from one habitat to the other, none became resident. Voles preferentially foraged in the richer of the two enclosures, even when I reversed treatments, and they foraged more in patches protected by mulched straw. The adaptive advantage of dispersal using a surrogate fitness proxy based on the voles' giving‐up densities mirrored that generated by theory. The convergence between theory and experiment yields much‐needed insight into our ability to test, predict, and hopefully resolve, the ecological, evolutionary, and conservation consequences of habitat loss. [ABSTRACT FROM AUTHOR]

Small mammals in the Horšianska dolina-Valley were researched first in 1984–86 and later in 2016–19. This paper seeks to identify and assess the species composition and dynamics of fleas (Siphonaptera) found in the valley on small mammals of Rodentia and Eulipotyphla and to compare findings from these two periods separated by thirty years. The results indicated deviations in small mammal and flea community similarity as well as in the small mammal indicator species for each habitat and flea indicator species for the small mammal species. A total 12 different species of small mammals were captured, and 12 flea species were collected. Eight flea species were detected in 1984–86 and ten species were found in 2016–19. In both periods A. penicilliger, C. assimilis, C. solutus, D. dasycnema, N. fasciatus were captured. The differences were that in the earlier period, the species uncovered were C. congener, P. bidentata, and P. soricis, while in the later period they were C. agyrtes, C. bisoctodentatus, M. turbidus, and R. integella. In the relationship between fleas and small mammals, C. solutus was the specific species for Apodemus flavicollis, while A. penicilliger and C. agyrtes were for Clethrionomys glareolus, and C. assimilis was for Microtus arvalis. [ABSTRACT FROM AUTHOR]

Morphometric analysis and evaluation of 260 striped field mice (Apodemus agrarius) were carried out to identify sexual size dimorphism in pelvic bones regarding the age of individuals and the reproductive history of females. Pelvic size was found to differ between subadult and adult individuals of both sexes. A comparison using the Mann–Whitney U test between the right and left parts of the pelvis showed statistically non-significant differences between the pelvis dimensions. In the inter-sexual comparison of both ages (subadult, adult), statistically significant differences were found for only four traits in adults: length of the coxal bone (LP1), width of the ischiopubis (WP1), length of the obturator foramen (LSF) and width of the obturator foramen (WSF). The two indices (WSF/LSF and WP1/LP2) evaluated clearly reflected changes in the pelvic shape, which were most pronounced in adult mice. For the group of subadult males and females, the differences in measured traits and indices were not as pronounced. Several analyses, such as the Mann–Whitney U test, principal component analysis (PCA) as well as discriminant analysis (DFA), showed sex differences in pelvic morphology and shape, although the two sexes overlapped. Similarly, one-way ANCOVA showed that there was a significant difference between the sexes for the adjusted means. Analyses showed that for a given body mass, it appears that females tend to have larger pelvises. Thus, the sexual dimorphism of females was related to pelvic size and shape in A. agrarius. The breeding history showed differences in pelvic dimensions in following direction: the nulliparous < primigravid < primiparous direction. [ABSTRACT FROM AUTHOR]

In this study, Taxonomic differences between Microtus guentheri and Microtus hartingi , which are similar in terms of external morphological features, were determined using linear morphometric, geometric morphometric, karyological and molecular analyses methods. Through classical morphometric (mean values) and geometric morphometric analyses of craniodental and mandible characters, influenced by various genetic, developmental, and functional processes, it was found that M. hartingi and M. guentheri exhibited notable differences in both mean linear measurements and shape. The Jackknife in classical morphometric analyses of samples, which underwent molecular and karyological species diagnoses, was higher than 88 % for each character. In geometric morphometric analyses, the Procrustes distance for shape follows the order Ventral < Dorsal < Mandible < M3

In 2010–2023, the dynamics of the population abundance and changes in the proportion of species in the community of small mammals (insectivores and rodents) inhabiting a slope larch forest in the vicinity of the city of Magadan (northern coast of the Sea of Okhotsk) was traced. The census of animals was carried out using Gero traps and cone traps (trap-line methods). In total, we analyzed 4700 trap-nights and 15 720 cone-nights. Altogether, 3384 individuals of 9 species belonging to the families of shrews (Soricidae), squirrels (Sciuridae), mice (Muridae), and hamsters (Cricetidae) were trapped. During the considered period, the relative abundance and the amplitude of its interannual fluctuations decreased in the populations of even-toothed shrews (Sorex isodon) and grey red-backed voles (Craseomys rufocanus). The proportion of Laxmann's shrews (S. caecutiens) and Korean field mice (Apodemus peninsulae) in the community increased 2.6 and 2.5 times, respectively, while the proportion of even-toothed shrew and grey red-backed vole decreased 2.8 times and 3 times, respectively. As a result, about 50% of the individuals in the samples were Laxmann's shrews and about 30% were northern red-backed voles (Clethrionomys rutilus). This, in turn, led to an increase in the dominance (the Simpson index increased from 0.21 to 0.34), a decrease in evenness (the Pielou index decreased from 0.87 to 0.61), and a significant decrease in the species diversity of the small mammal community (the Shannon index decreased from 1.7 to 1.3; t = 10.90, p < 0.001). [ABSTRACT FROM AUTHOR]

Cyclic rodent populations exhibit pronounced changes in body mass associated with the population cycle phase, long-known as Chitty effect. Although Chitty effect is a common epiphenomenon in both America and Europe, there is still incomplete evidence about the generality of these patterns across the entire range of most species. Moreover, despite decades of research, the underlying factors driving Chitty effect remains poorly understood. Here, we examined the influence of intrinsic and extrinsic factors that may underlie observed patterns in vole size variation in the Iberian common vole Microtus arvalis asturianus. We weighed and measured 2816 adult voles that were captured during 6 trapping periods. Vole numbers and body mass showed strong period- and phase-related variation both in females and males, demonstrating marked Chitty effect in the studied population. Body mass of adult males correlated with body length, evidencing that heavier males are also structurally larger. Statistical models showed that probability of occurrence of large-sized vole (> 37 g) was significantly more likely in reproductive males, during increase and peak phases, and it was modulated by habitat, with crop fields and field margins between crops showing an increased likelihood. We suggest an effect of the habitat on vole body mass mediated by predation. [ABSTRACT FROM AUTHOR]

An analysis of the genetic diversity of the field vole was carried out with the inclusion of new data on the complete sequences of the cytochrome b gene from the least studied area of the range of the species—the central part of Northern Eurasia (20 localities of the East European Plain, the Urals, Western and Eastern Siberia). The obtained results are generally consistent with modern view on the phylogeography of the species, but indicate the previously not investigated genetic heterogeneity of the Eastern clade, which occupies the entire Asian part of the range of the species and its European part to Northern and Eastern Europe. A comparison of the results of analysis of genetic diversity with the age of paleontological findings carried out using the Urals as an example allows one to assume that climatic changes in the Late Pleistocene and Holocene could not have led to the complete extinction of the species in the region, but to the spatial redistribution of its populations and to the complete or partial replacement of some genetic groups by others. [ABSTRACT FROM AUTHOR]

Copyright of ANKEM Antibiyotik & Kemoterapi Dergisi is the property of ANKEM Antibiyotik & Kemoterapi Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spontaneous choriocarcinomas are rare, highly vascular, malignant trophoblastic tumors that occur in humans and animals. This report describes the unusual spontaneous presentation of 4 choriocarcinomas within the subcutaneous tissues of 4, multiparous but nongravid, Amargosa voles (Microtus californicus scirpensis) from a captive breeding colony. Two subcutaneous neoplasms were composed of multifocal discohesive and infiltrative aggregates of medium to large trophoblasts and cytotrophoblasts within a fibrovascular stroma. Neoplastic cells were associated with variably sized thrombi and cavitary areas of hemorrhage and necrosis. Two subcutaneous tumors were predominantly composed of expansile, blood-filled, cystic spaces lined by neoplastic cytotrophoblasts and occasionally contained medium to large trophoblasts. Trophoblasts and cytotrophoblasts were positive for pancytokeratin and cytokeratin 8/18, negative for alpha-fetoprotein, and contained intracytoplasmic Periodic acid–Schiff (PAS)-positive glycogen in all 4 tumors. In species with hemochorial placentation, migration of trophoblasts into maternal circulation with embolization to distant nonreproductive tissues occurs and may explain the unusual subcutaneous distribution of these 4 tumors. The 2 multiloculated paucicellular tumors may represent an early stage of neoplastic transformation. To the authors' knowledge, this is the first report characterizing choriocarcinomas in extrareproductive sites in rodents. [ABSTRACT FROM AUTHOR]

Stress-induced illnesses, like major depression, are among the leading causes of disability across the world. Consequently, there is a dire need for the validation of translationally-suited animal models incorporating social stress to uncover the etiology of depression. Prairie voles (Microtus ochrogaster) are more translationally relevant than many other rodent models as they display monogamous social and bi-parental behaviors. Therefore, we evaluated whether a novel social defeat stress (SDS) model in male prairie voles induces depression-relevant behavioral outcomes. Adult sexually-naïve male prairie voles experienced SDS bouts from a conspecific pair-bonded male aggressor, 10 min per day for 10 consecutive days. Non-stressed controls (same-sex siblings) were housed in similar conditions but never experienced physical stress. Twenty-four h later, voles were evaluated in social interaction, sucrose preference, and Morris water maze tests – behavioral endpoints validated to assess social withdrawal, anhedonia-related behavior, and spatial memory performance, respectively. SDS-exposed voles displayed lower sociability and body weight, decreased preference for a sucrose solution, and impairment of spatial memory retrieval. Importantly, no differences in general locomotor activity were observed as a function of SDS exposure. This study does not include female voles in the experimental design. We found that repeated SDS exposure, in male prairie voles, results in a depression-relevant phenotype resembling an anhedonia-like outcome (per reductions in sucrose preference) along with social withdrawal and spatial memory impairment – highlighting that the prairie vole is a valuable model with potential to study the neurobiology of social stress-induced depression-related outcomes. • Social defeat stress decreases social behavior in adult male prairie voles • Social defeat stress decreases sucrose preference in adult male prairie voles • Social defeat stress impairs spatial memory in adult male prairie voles • Vole social defeat stress displays strong face validity as a model for the study of depression-related phenotypes [ABSTRACT FROM AUTHOR]

Rodents, including the striped field mouse (Apodemus agrarius), play vital roles in ecosystem functioning, with their gut microbiota contributing significantly to various ecological processes. Here, we investigated the structure and function of 94 wild A. agrarius individuals from 7 geographic populations (45°57′ N, 126°48′ E; 45°87′ N, 126°37′ E; 45°50′ N, 125°31′ E; 45°59′ N, 124°37′ E; 46°01′ N, 124°88′ E; 46°01′ N, 124°88′ E; 46°01′ N, 124°88′ E), revealing two distinct enterotypes (Type1 and Type2) for the first time. Each enterotype showed unique microbial diversity, functions, and assembly processes. Firmicutes and Bacteroidetes dominated, with a significant presence of Lactobacillus and Muribaculaceae. Functional analysis highlighted metabolic differences, with Type1 emphasizing nutrient processing and Type2 showing higher energy production capacity. The analysis of the neutral model and the null model revealed a mix of stochastic (drift and homogenizing dispersal) and deterministic processes (homogenous selection) that shape the assembly of the microbiota, with subtle differences in the assembly processes between the two enterotypes. Correlation analysis showed that elevation and BMI were associated with the phylogenetic turnover of microbial communities, suggesting that variations in these factors may influence the composition and diversity of the gut microbiota in A. agrarius. Our study sheds light on gut microbial dynamics in wild A. agrarius populations, highlighting the importance of considering ecological and physiological factors in understanding host–microbiota interactions. [ABSTRACT FROM AUTHOR]

Patterns of introgression of several genetic markers across the hybrid zone between allied species of the common vole Microtus arvalis s. str. and M. obscurus was studied in four of its sections: in northwest Nizhny Novgorod oblast, east Vladimir and southwest Nizhny Novgorod oblasts, south Lipetsk oblast, and northwest Voronezh oblast. Analysis of the clinal variability for three molecular genetic markers (cytb, tp53, SMCY11) and for karyotypes showed a structural similarity between the "Vladimir–Nizhny Novgorod," "Nizhny Novgorod," and "Voronezh" sections. The maximum width was shown for the cytb cline; the minimum width was shown for the SMCY11 cline; the tp53 cline and chromosomal cline occupy an intermediate position for this parameter. Furthermore, in these transects, the center of the cline for the cytb is shifted southeastward (into the distribution range of M. obscurus) from the centers of three other clines. The revealed asymmetric introgression of mitochondrial genome from M. arvalis to M. obscurus may be explained by the fact that the hybrid zone was formed as a result of invasion of M. obscurus into the range of M. arvalis. The "Lipetsk" transect differs from the three above-mentioned transects in very narrow clines with nearly coinciding centers. Such characteristics of the "Lipetsk" transect are obviously caused by localization of the hybrid zone in this section along Voronezh River. The obtained results led us to suppose that the structure of the studied hybrid zone is determined mainly by coincidence (or noncoincidence) of its center with local physical barriers. [ABSTRACT FROM AUTHOR]

Rodent populations often undergo large, regular fluctuations. We studied immunological condition and physiological stress in the common vole and how it varied with environmental factors linked with population fluctuations, namely flea and Francisella tularensis (the bacterium causing tularemia) prevalence. We used two leukocyte indices, neutrophil-to-lymphocyte ratio (N:L) and proportion of eosinophils, as physiological long-term stress indicators, and measured levels of immunoglobulins (Ig) as a generic index of immunological condition. Leukocyte indices showed a hump-shaped relationship with Ig levels, consistent with an interdependence between physiological stress and immunological condition. N:L was negatively associated with vole density only in males. Eosinophil proportion was explained by the interaction between flea burden and tularemia prevalence, with highest levels in flea-infested voles also infected with tularemia. Ig levels did not vary with sex or flea prevalence but increased in tularemia-infected voles. When Ig levels were included as covariates in our models, the associations between leukocyte indices and environmental factors remained significant. Results suggest sex-specific associations between physiological stress and population density, and an influence of tularemia infection depending on ectoparasite load. We recommend using immunological parameters complementarily to leukocyte indices when studying physiological stress and infection dynamics in wild populations. [ABSTRACT FROM AUTHOR]

A methodology for monitoring the food resources of two threatened species of European mustelids was developed and successfully tested. It was based on abundance estimates of rodents considered the main prey of the Marbled and the Steppe polecats in Bulgaria: the European ground squirrel, the lesser blind mole-rat, and the voles. Most of the sampling sites were characterized by low abundance of all three investigated prey species. Differences in rodent species' abundance were observed among regions. Among the five examined regions, West Central Bulgaria, which exhibits the highest occurrence of the marbled polecat, is characterized by the most abundant prey, although the optimal prey was not present in the studied sites. Our results suggest that in the western part of its range the distribution of the marbled polecat may not be as reliant on the presence of the European ground squirrel as traditionally assumed. Being simple and unexpensive the proposed transect method for assessment of the polecats' prey abundance is suitable for conservation purposes and national or regional monitoring. [ABSTRACT FROM AUTHOR]

This article discusses the use of naturalistic, field assays with free-ranging animals as alternatives to laboratory models in scientific research. The authors highlight the differences between field and laboratory research, noting that while laboratory studies provide control and standardization, field studies offer important contextual factors. The article presents several examples of field assays that have replaced or supplemented laboratory tests, including studies on European catfish, rhesus macaques, wild mice, Tanimbar corellas, and prairie voles. The authors emphasize the strengths and weaknesses of these assays and argue for the importance of incorporating more naturalistic approaches in research. [Extracted from the article]

We conducted a habitat suitability assessment for two burrowing rodents, Anatolian or Nehring’s blind mole rat (Nannospalax xanthodon) and Harting’s vole (Microtus hartingi), on the island of Lesvos using a niche-based approach. We collected data on the presence of the two species across the island and selected several environmental variables, including land cover, geology, and habitat topography, to assess their influence on habitat suitability. We used the Maxent species distribution modelling algorithm to predict suitable habitats. The results showed that both species preferred habitats with low slopes and specific geological substrates, i.e., alluvial deposits and volcanic rocks. M. hartingi showed a preference for open habitats such as saltmarshes and non-irrigated arable land, while N. xanthodon preferred non-irrigated arable land, pastures, and discontinuous urban fabric. The model predicted a wider area of suitable habitats for Microtus hartingi compared to N. xanthodon. Interestingly, the two species are absent from the southeastern part of the island despite our model predicting high suitability; this indicates that a natural barrier of hilly terrain, extensive pine forests, and limestone rock formations may exist that impedes dispersal. Our study provides valuable insights into the habitat preferences of these two burrowing rodents on the island of Lesvos, which can inform biodiversity conservation and ecosystem management strategies.

The adaptive effects of inbreeding are understudied, but accumulating evidence suggests that it plays a major adaptive role in speciation, as populations with a history of inbreeding are more prone to it. Differences in inbreeding tolerance in two populations of Microtus hartingi voles were studied through a series of experiments on reproductive behaviour and partner choice. Modelling an artificial polygyny via the formation of trios composed of a brother, sister, and an unrelated female has shown an uneven attitude towards inbreeding, which was closely linked to the reproduction strategy: voles of the Rhodopean population (RP) would reproduce communally with only a moderate decrease in reproduction success, while in monogamous M. hartingi ankaraensis voles from Central Anatolia (CAP), the reproductive success dropped almost to zero due to severe social stress resulting in heavily antagonistic behaviour between females; aggression levels rose with maturation. Studies of reproduction in pairs of relatives revealed the absence of inbreeding avoidance in the polygynous population (RP) and a sharp decrease in reproduction probability in the monogamous subspecies (CAP). Olfactory three-choice behavioural tests have proven that voles do not choose the smell randomly, juveniles do not have partner preferences, and adults choose the unrelated individual's odour. RP voles prefer to mate with kin first, whereas CAP voles mate with non-kin first. The differences in reproductive strategy might have evolved due to habitat fragmentation and restriction of natal dispersal in the RP which has been isolated from the ancient Anatolian Microtus hartingi population since the Pleistocene. The adaptation to communal reproduction via kin selection resulted in increased inbreeding tolerance. [ABSTRACT FROM AUTHOR]

Continuous predictors of survival present a challenge in the analysis of data from studies of marked individuals if they vary over time and can only be observed when individuals are captured. Existing methods to study the effects of such variables have followed one of two approaches. The first is to model the joint distribution of the predictor and the observed capture histories, and the second is to draw inference from the likelihood conditional on events that depend only on observed predictor values, called the trinomial model. Previous comparison of these approaches found that joint modelling provided more precise inference about the effect of the covariate while the trinomial model was less prone to issues of model mis‐specification. However, we believe that an important issue was missed. We show through mathematical analysis and numerical simulation that the trinomial model is not identifiable when the predictor has no effect on the survival probability. This also causes inferences from the trinomial model to be imprecise when the effect of the covariate on the survival probability is small. We also analyse data on the effect of body mass on the survival of meadow voles to demonstrate the importance of this issue in real applications. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the relationship between the breeding parameters and food composition of the common barnowl (Tyto alba) comparing the outbreak and subsequent crash periods of the common vole (Microtus arvalis) as the barn owl’s main prey. For the analyses, data of 29 (2014 outbreak: 6, 2016 crash: 8; 2019 outbreak: 7, 2021 crash: 7) breeding pairs of barn owls were selected. First, we examined the differences between the breeding parameters (clutch size, number of hatchlings and fledglings), the main and alternative prey taxa (common vole and Apodemus genus), the two derived indices (trophic level index, Microtinae/Murinae ratio) between the given outbreaks and subsequent crashes as well as the cumulative data of the two demographic periods. In addition, we analysed the difference in rank-abundance distribution of prey composition comparing the outbreak and crash. We investigated the relationships between breeding parameters and demographic periods, the main and alternative prey taxa and the two derived indices using generalized linear mixed models (GLMM). The clutch size was significantly higher in both outbreaks than the crash periods, while the number of hatchlings and fledglings differed only between the second outbreak and crash period. Regarding the cumulative data of outbreaks and crashes, the values of all three breeding parameters were significantly higher in the outbreak period of the common vole. Our results highlighted the main prey role of common voles during the outbreak, as well as the importance of the Apodemus genus during the crash period. GLMM analysis supported that all three breeding parameters were positively determined by the ommon vole’s abundance in the diet of barn owls in outbreak and crash periods, while the reproductive output was positively influenced common by the frequency of the Apodemus genus as potential alternative prey in the crash period. [ABSTRACT FROM AUTHOR]

Hemorrhagic fever with renal syndrome (HFRS) is caused by hantaviruses (HVs) and is endemic in Zhejiang Province, China. In this study, we aimed to explore the changing epidemiology of HFRS cases and the dynamics of hantavirus hosts in Zhejiang Province. Joinpoint regression was used to analyze long-term trends in the incidence of HFRS. The comparison of animal density at different stages was conducted using the Mann–Whitney Test. A comparison of HV carriage rates between stages and species was performed using the chi-square test. The incidence of HFRS shows a continuous downward trend. Cases are widely distributed in all counties of Zhejiang Province except Shengsi County. There was a high incidence belt from west to east, with low incidence in the south and north. The HFRS epidemic showed two seasonal peaks in Zhejiang Province, which were winter and summer. It showed a marked increase in the age of the incidence population. A total of 23,073 minibeasts from 21 species were captured. Positive results were detected in the lung tissues of 14 rodent species and 1 shrew species. A total of 80% of the positive results were from striped field mice and brown rats. No difference in HV carriage rates between striped field mice and brown rats was observed (χ2 = 0.258, p = 0.611). [ABSTRACT FROM AUTHOR]

The hearing abilities of mammals are impacted by factors such as social cues, habitat, and physical characteristics. Despite being used commonly to study social behaviors, hearing of the monogamous prairie vole (Microtus ochrogaster) has never been characterized. In this study, anatomical features are measured and auditory brainstem responses (ABRs) are used to measure auditory capabilities of prairie voles, characterizing monaural and binaural hearing and hearing range. Sexually naive male and female voles were measured to characterize differences due to sex. It was found that prairie voles show a hearing range with greatest sensitivity between 8 and 32 kHz, binaural hearing across interaural time difference ranges appropriate for their head sizes. No differences are shown between the sexes in binaural hearing or hearing range (except at 1 kHz), however, female voles have increased amplitude of peripheral ABR waves I and II and longer latency of waves III and IV compared to males. The results confirm that prairie voles have a broad hearing range, binaural hearing consistent with rodents of similar size, and differences in amplitudes and thresholds of monaural physiological measures between the sexes. These data further highlight the necessity to understand sex-specific differences in neural processing that may underly variability in responses between sexes. [ABSTRACT FROM AUTHOR]

We collected 280 pellets cast by Tyto alba (Barn Owl) from 1996, 1997, and 1998 from a silo roost in Harrogate, TN. Blarina brevicauda (Northern Short-tailed Shrew, 42.2%), Synaptomys cooperi (Southern Bog Lemming, 13.6%), Cryptotis parva (Least Shrew, 10.9%), Sigmodon hispidus (Hispid Cotton Rat, 7.9%), Microtus spp. (4.9%), and Aves spp. (4.3%) comprised most of the prey items. Compared to a previous study, percentages of Northern Short-tailed Shrews were proportionately greater than those of Southern Bog Lemmings in the 1996-1998 pellets. Precipitation and fluctuations in prey populations might be responsible for the disparities in diet composition between pellet collections, but more research is necessary to investigate a possible relationship. [ABSTRACT FROM AUTHOR]

Introduction: The prairie vole (Microtus ochrogaster) is a socially monogamous species that, after cohabitation with mating, forms an enduring pair bond. It has been suggested that female prairie voles avoid mating with fathers and siblings to prevent inbreeding depression. However, controlled laboratory tests of preferences involving males with varying degree of relatedness have not been conducted. Methods: To address this, we employed a multiple socio-sexual preference arena consisting of four adjacent cylinders arranged in a closed circle. In each cylinder, we placed a male of varying relatedness to the experimental female (i.e., father, sibling, first-degree cousin, and unrelated males) and registered their behavior for five hours. Male socio-sexual preference was determined by the proportion of time spent in each male's chamber, which can be driven by affiliative preferences for the father and sibling and sexual attraction for the cousin and unrelated males. Mating preference was analyzed as the frequency of mating with each male. We hypothesized that receptive females would show sexual attraction and mating preferences for the unrelated males and cousins and affiliative preferences for the fathers and siblings. Results: Our analyses showed that females spent more time with first-degree cousins and mated more often with them compared to unrelated males, siblings, or fathers. However, complete inbreeding avoidance was not observed, and some females mated with siblings, fathers, or both. Discussion: Although our results did not support the hypothesis, they are consistent with other studies that have argued that mating with first-degree cousins optimizes the costs and benefits associated with inbreeding and outbreeding. [ABSTRACT FROM AUTHOR]

The East European vole is a facultative synanthropic species that actively spreads in the eastern part of northern Eurasia. The distribution area of the species in Irkutsk oblast has been known as a disjunct part of the range since the 1980s. Our dataset includes 98 individuals caught in 2016–2017 and 2021–2023 in the eastern segment of the species'dispersal area, where the East European vole was first discovered in the early 2010s. Animals were caught in anthropogenically transformed landscapes spanning from the outskirts of Irkutsk to kilometer 23 of the Goloustnenskii Tract; trapping in natural biotopes revealed no M. rossiaemeridionalis. Species identification was based on molecular genetic markers. Morphological and fine structural characteristics of molar teeth were studied using both light and scanning electron microscopy. The complexity of the occlusal surface, the alternation patterns of the enamel cutting edges (occlusal regularity), and the presence or absence of atypical extra elements such as prismatic folds and prisms in places of the early cricetid dental features were assessed. The estimates of the complexity and regularity patterns fell within the range of dental variability known for the continuous distribution area of the species. The atypical extra elements on molars were described in M. rossiaemeridionalis for the first time based on material coming from two trapping sites. With the maximum manifestation of these folds, a supernumerary prism, topologically corresponding to the hypoconid, is separated from the posterior lobe of the lower teeth. The distribution of lamellar and radial enamel on the supernumerary prism is not consistent with the functionally significant and evolutionarily determined distribution of enamel types on teeth of the genus Microtus. It is concluded that the studied local micropopulation exhibits the phenotypic consequences of population restoration from a small number of founders. Apparently, the species in the study area faces multiple successive cases of establishment (naturalization) in a new territory. The results obtained confirm the prospects of using dental characters for monitoring Arvicolinae species, the distribution boundaries of which are subject to significant spatial changes in the relatively short periods of time available for observation. [ABSTRACT FROM AUTHOR]

The fossil fauna of small mammals from the Imanay cave deposits (53°02′ N, 56°26′ E), Southern Urals, Russia, was studied. Species of open habitats prevailed, the narrow-headed vole (Microtus (Stenocranius) gregalis) being dominant. Two types of fauna were identified that characterize its composition and structure at the end of the Late Pleistocene and, presumably, in the Early Holocene. A codominant species of the first type of fauna (lower and middle cave deposits) was the steppe lemming (Lagurus lagurus). This type was characterized by a sharp predominance (83.0–92.2%) of steppe species and a low proportion (1.5–3.9%) of forest mammal species. Open landscapes must have dominated and been common in the Late Glacial in the southern part of the Ural Mountains. The pika (Ochotona sp.) co-dominated in the fauna of the second type (upper cave deposits), with relatively high proportions of forest species (14.3–21.4%) indicating the appearance of forest formations in the Late Glacial or Early Holocene in this area. Samples of the first lower molars of narrow-headed voles were characterized by a high proportion of teeth (>50%) with simple variants of the structure of the anteroconid cap ("gregaloid" morphotype). High proportions (up to 51.6%) of the "transiens" morphotype were recorded among the first lower molars of the steppe lemming. Among the teeth in the lower half of the cave deposits, rootless cemented first lower molars (m1) and third upper molars (M3) were found with wide merging triangles T4–T5 (m1) and T2–T (M3). This structure of the chewing surface of the molars was typical of the ancient voles Microtus (Stenocranius) gregaloides and M. (Terricola) arvalidens from the fauna of the first half of the Early Pleistocene and the second half of the Middle Pleistocene. [ABSTRACT FROM AUTHOR]

Successful reproduction of two subspecies of Harting's vole in monogamous pairs (monogamous groups, 35 pairs for each) was shown. The results obtained in modeling the experimental polygyny revealed a different attitude of females of the two subspecies to the formation of communal groups. In polygynous groups of M. h. lydius, regardless of the relationship of the females (35 groups consisting of sisters and 20 groups of unrelated females), the intensity of reproduction and the proportion of successfully reared pups decreased significantly compared to the monogamous groups. With high energy costs for reproduction, there were significantly fewer reared pups per mother giving birth than in the monogamous groups, thus suggesting the predominance of monogamy in this subspecies. On the contrary, related females of M. h. hartingi bred successfully in communal groups (35 groups of sisters), demonstrating a high tolerance, a tendency to co-rearing and feeding the pups, and low infant mortality. In polygynous groups consisting of unrelated females (20 groups), reproductive success decreased due to increased infant mortality. Possible benefits of communal reproduction in this subspecies are discussed, as well as the likely relationship with habitat fragmentation under such conditions and with a lack of vacancies for the dispersal of young animals, which may be an important adaptation for this subspecies of voles. [ABSTRACT FROM AUTHOR]

The creeping vole Microtus oregoni exhibits remarkably transformed sex chromosome biology, with complete chromosome drive/drag, X‐Y fusions, sex reversed X complements, biased X inactivation, and X chromosome degradation. Beginning with a selfish X chromosome, I propose a series of adaptations leading to this system, each compensating for deleterious consequences of the preceding adaptation: (1) YY embryonic inviability favored evolution of a selfish feminizing X chromosome; (2) the consequent Y chromosome transmission disadvantage favored X‐Y fusion ("XP"); (3) Xist‐based silencing of Y‐derived XP genes favored a second X‐Y fusion ("XM"); (4) X chromosome dosage‐related costs in XPXM males favored the evolution of XM loss during spermatogenesis; (5) X chromosomal dosage‐related costs in XM0 females favored the evolution of XM drive during oogenesis; and (6) degradation of the non‐recombining XP favored the evolution of biased X chromosome inactivation. I discuss recurrent rodent sex chromosome transformation, and selfish genes as a constructive force in evolution. [ABSTRACT FROM AUTHOR]

A characteristic based on long-term (1958–2018) field and stationary studies is given for the abundance and the demographic structure of the population, the course of reproduction, nutrition, and other ecological features common to twin species of the common vole (Microtus arvalis sensu lato). It has been found that the northern boundary of their distribution in the past sixty years first moved north and reached 63°40′ N, and then it also quickly retreated to the south. A sharp reduction in sown areas, primarily cereals caused by the reorientation of agriculture from grain to dairy and vegetables is the reason for the latter. This, as well as the replacement of common voles with native species of rodents (tundra, water, short-tailed field, and bank voles), caused a sharp decrease in the number and narrowing of the range of species in the eastern regions of Fennoscandia. The main place in the diet of twin species is occupied by the green mass of herbaceous plants (the occurrence rate is 72%), the smaller one is occupied by seeds (25%), and the bark of trees is a very rare component (3%). Reproduction in the conditions of the northern periphery of the range proceeds only during one rather limited spring–summer season. The age and sex composition of the population is heterogeneous and varies seasonally. [ABSTRACT FROM AUTHOR]

In the present study, we investigated food resource niche parameters and the degree of specialization of two local Western Barn Owl (Tyto alba) populations in two different demographic phases as the crash (2015–2016) and outbreak (2019–2020) of the Common Vole (Microtus arvalis). The study was conducted in two parts of the Transdanubian region of Hungary, namely in Duna-Drava National Park (DDNP) in the southeastern part, and in Fertő-Hanság National Park (FHNP) in the north-western part. For the analysis, we used food consumption data of 20–20 randomly selected breeding pairs from the DDNP population, while 14 and 17 breeding pairs in FHNP population in the crash and outbreak periods, respectively. Since the small mammal consumption of owls represented 99.3% of the total number of individuals, only data of small mammals as main food resource were taken into account during the analysis. Based on a trait-based framework which taking into account the resemblance between resources, Rao's quadratic entropy metrics was used to estimate the food resource niche breadth at local owl populations and the breeding pair level. The small mammal resource utilization of owls was dependent on populations. The niche breadth of DDNP population was significantly smaller than FHNP population. The estimated niche overlap at the individual level was significantly different between the two populations. The calculated value of specialization of barn owl populations was significantly higher in north-western than south-eastern population. The niche breadth of the owl population living in the DDNP was significantly higher during the crash period. In contrast, the estimated niche breadth of the population living in FHNP did not differ significantly between the two demographic phases. Based on our result, the applied trait-based framework of resource niche pattern analysis demonstrated that the differences of niche breadth were explored in more detail by this method between the local Barn Owl populations of different geographical region. [ABSTRACT FROM AUTHOR]

Microtus thomasi (Rodentia: Arvicolinae), a fossorial vole endemic to the SW Balkans, uses a variety of substrates but its underground behavior remains poorly understood. This study examines the architecture and utilization of M. thomasi burrow systems in NW Peloponnese, Greece. In particular, eight burrow systems were meticulously excavated and studied, with comprehensive measurements taken of key characteristics, including length, depth, soil mounds, and surface openings. Key coordinates were recorded using a differential GPS device for detailed mapping and fractal dimension analysis using the box-counting method was employed to assess burrow system complexity. Soil samples were analyzed for particle size and chemical composition, and vegetation types at each site were identified. We did not find statistically significant correlations between size and complexity of the burrow systems and soil composition, altitude, or specific soil components. On the other hand, we did observe statistically significant differences in tunnel diameter between two burrow systems and in tunnel depth between more. Moreover, our study showed that more than one same-sex individual can occupy a single burrow system and not just an adult male-female pair, that was previously recorded, indicating the need for further study of the social behavior of this vole species. This study provides valuable insights into the underground behavior of M. thomasi by providing information on the features of its burrow systems, thus contributing to our understanding of its biology. [ABSTRACT FROM AUTHOR]

The present review is a compilation of the published data on the ecology and social behavior of the social vole. Field studies provide evidence that these voles live in family groups consisting of 1 adult male, 1 or 2 breeding females, and their offspring (1 or 2 litters). The social vole is capable of year-round reproduction, but in arid regions, the voles demonstrate seasonality in breeding. The mating system of this species may be defined as behavioral monogamy. A typical feature of the space use system is territoriality characterized by a locus-dependent dominance in relationships between neighboring breeding pairs as well as family groups. The family group social organization may be defined as consistent relationships without a dominant hierarchy. Social voles are cooperative in defending their territories, constructing burrows, digging underground tunnels, maintaining nests, and raising young. Cooperation appears to enhance the survival of family groups of this species under the extreme climatic conditions of Central Asia. [ABSTRACT FROM AUTHOR]

Death of a loved one is recognized as one of life's greatest stresses, and 10%–20% of bereaved individuals will experience a complicated or prolonged grieving period that is characterized by intense yearning for the deceased. The monogamous prairie vole (Microtus ochrogaster) is a rodent species that forms pair bonds between breeding partners and has been used to study the neurobiology of social behaviors and isolation. Male prairie voles do not display distress after isolation from a familiar, same‐sex conspecific; however, separation from a bonded female partner increases emotional, stress‐related, and proximity‐seeking behaviors. Here, we tested the investigatory response of male voles to partner odor during a period of social loss. We found that males who lost their partner spent significantly more time investigating partner odor but not non‐partner social odor or food odor. Bachelor males and males in intact pairings did not respond uniquely to any odor. Furthermore, we examined dopamine (DA) receptor mRNA expression in the anterior insula cortex (aIC), nucleus accumbens (NAc), and anterior cingulate (ACC), regions with higher activation in grieving humans. While we found some effects of relationship type on DRD1 and DRD2 expression in some of these regions, loss of a high‐quality opposite‐sex relationship had a significant effect on DA receptor expression, with pair‐bonded/loss males having higher expression in the aIC and ACC compared with pair‐bonded/intact and nonbonded/loss males. Together, these data suggest that both relationship type and relationship quality affect reunion‐seeking behavior and motivational neurocircuits following social loss of a bonded partner. [ABSTRACT FROM AUTHOR]

The recovery of some predator species in recent decades has intensified conflicts between humans and predators. To mitigate these conflicts, knowledge of predator-prey relationships is needed. The aim of this study was to estimate the predation rate of common buzzards Buteo buteo on young brown hares Lepus europaeus and to compare the magnitude of this predation between two areas that differ in the type of agricultural landscape, i.e. the size of crop fields. In the years 2005–2014, the composition of buzzard diet was studied in western Poland by analysing pellets and prey remains of nestlings and adult birds (7971 prey items identified) and estimating the abundance of buzzards (searching for and observing their nests) and hares (spotlight counts) in two adjacent areas (75 km2 in total) with small and large fields. The diet of common buzzards was dominated by common voles Microtus arvalis, and the frequency of hares ranged from 1.1% of prey items in the nestling diet to 0.2% in the diet of post-breeding individuals. The total number of hares consumed by buzzards during the spring-summer season in the whole study area amounted to 2.94 per km2, which is equal to 7.8–15.3% of the young hares born per km2. However, the predation rate estimated based on the nestling food was 2.6 times lower in small fields than in large fields. Thus, this study suggests that reducing buzzard predation on young hares can be achieved by habitat management, i.e. the creation of agricultural landscapes with numerous field boundaries. [ABSTRACT FROM AUTHOR]

The distinct accumulation patterns of persistent organic pollutants (POPs) among granivorous groups and the biomagnification of POPs from crops to granivorous species are still unclear. In this study, occurrence and biomagnification of POPs in three granivorous species including spotted dove (Spilopelia chinensis), scaly-breasted munia (Lonchura punctulata), and reed vole (Microtus fortis Buechner) from a former e-waste recycling site were investigated. Concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in granivorous species ranged from 41.5 to 1370 and 21.1 to 3890 ng/g lipid weight, respectively. PCBs and PBDEs were the main POPs in birds and vole, while decabromodiphenyl ethane (DBDPE) and PBDEs were predominant POPs in crops. The dominance of BDE 209 was observed in samples, with few exceptions. Biomagnification factors (BMFs) of POPs in birds and vole were measured. BMFs of most POPs in vole were higher than those in birds, indicating that POPs had greater biomagnification potential in vole. Species-specific biomagnification of POPs might be affected by many factors, such as physiochemical properties and metabolic capability of POPs. There was significant correlation between concentration ratios of POPs in muscle/air and log KOA, which demonstrated that respiratory elimination to air affects biomagnification of POPs in granivorous birds and vole. [ABSTRACT FROM AUTHOR]

In the literature, 114 species of arthropods associated to Microtus oeconomus have been reported in the entire area of their occurrence. There are eight species of hard ticks, 52 species of gamasid and chigger mites, 47 species of fleas and seven species of sucking lice. In general, the dominant parasites of the Palearctic and Nearctic root vole populations are either western or entire Palearctic species. The analysis of the geographical range of their occurrence indicates that most of them occur both in Europe and Asia. Throughout Europe, Asia and America (Holarctic realm), root voles share 13 species of mites, seven species of fleas, and three species of sucking lice. Ectoparasite species split between two continents, most of them are found in both Europe and Asia (Palearctic region). Here belong three species of ixodid ticks, sixteen species of mites, seven species of fleas and two species of sucking lice. In Asia and the North American continents (Holarctic realm excluding Europe) populations of root voles share only one tick species, two species of mites, three species of fleas and one species of sucking lice. Of the parasitic species found only in Western Palearctic, excluding Asia, root voles are infested by three ixodid tick species, 14 mite species, and 13 flea species. Among the parasitic arthropods affecting root vole only in Eastern Palearctic, excluding Europe, one tick species, four mite species and seven flea species occur. There are only three mite species, ten flea and one sucking louse species on voles that inhabit North America (Nearctic region). Associated arthropods are obligate and facultative parasites or nidicolic and edaphic species. Seasonal changes in numbers of ticks, parasitic mites, sucking lice, fleas have also been observed. [ABSTRACT FROM AUTHOR]

Grey voles Microtus sensu lato represent one of the youngest and most successful radiations of rodents in the Holarctic that gave rise to several genera and over 60 living species. Despite abundant fossil record encompassing up to one million years, the early stages of Microtus' evolution remain poorly understood. We describe Microtus voles from fluvial deposits (Tobolsky Horizon, the Late Middle Pleistocene) found in 2019–2020 in Gornopravdinsk 2, West Siberia. Based on linear measurements, m1 morphotypes, and configuration of mandibular masseteric crests, we identify the sample as a new taxon M. nivaloides lidiae ssp. nov. It appears more advanced than type specimens of M. nivaloides sensu stricto from West Runton Freshwater Bed (the Early Middle Pleistocene, Great Britain), and falls within the range of m1 variability of M. nivaloides sensu lato from the Middle Pleistocene of Eastern Europe. M. n. lidiae is found in a non-analogue faunal assemblage with Lemmus sibiricus, Dicrostonyx simplicior, Alexandromys oeconomus, Lasiopodomys gregalis, rare Clethrionomys cf. glareolus, Alexandromys aut Microtus cf. malei, Lagurus sp. We hypothesise that M. n. lidiae was a meadow-steppe element in the Middle Pleistocene communities and a terminal taxon in the 'nivaloides' clade that became extinct with no descendants. [ABSTRACT FROM AUTHOR]