Effects of roads on small-mammal movements: Opportunities and risks of vegetation management on roadsides.

Roads can block animal movement and reduce persistence of species living in road surroundings. Movement restrictions on local populations may even increase extinction risk of abundant small mammals. However, road verges (road managed area between the edge of the road and the beginning of private land) may provide refuge and corridors for small mammals when properly managed. Information on the effects of roads and roadside management on small-mammal movement is still scarce for low traffic roads (<20,000 vehicles per day) crossing well-preserved habitats. We aimed to fill this gap by comparing fine-scale movement patterns of wood mice (Apodemus sylvaticus) in a road and in a similar roadless area without management. Both areas consisted of a well-preserved Mediterranean agro-silvo pastoral system. We studied several movement patterns: road crossings, verge use, length, and direction of movement. Additionally, we assessed how roadside management, animals' sex and residency status, season and microhabitat affect movement at the road area. At the roadless area, we defined a virtual road and verges at equivalent locations to the road area for comparison purposes. We gathered capture-mark-recapture data for two years to characterize movement patterns. Wood mice tended to avoid the road by crossing it less often and moving away from it more frequently than from equivalent locations in the roadless area. Wood mice used road verges more frequently than virtual verges and moved more often parallel to the road than to the virtual road. Road crossings were more frequent after firebreak openings (strips of mowed land) in surrounding areas and near taller shrubs. Also, males used road verges more often than females. Differences on several movement patterns between areas and their trends within the road area can be explained mainly by the presence of the road and roadside vegetation management (e.g., firebreaks openings). We suggest roadside vegetation management practices (e.g., avoid land mowing; maintain vegetation strips) to promote the role of verges as refuges and/or corridors for small mammals.

Road verges provide connectivity for small mammals: A case study with wood mice (Apodemus sylvaticus) in an agro-silvo pastoral system.

Roads disrupt landscape connectivity for many terrestrial mammals. These infrastructures can be barriers to movement thereby threatening population persistence. Nonetheless, small mammals may use road verges as habitat or corridor, thus increasing migration across intensively managed landscapes. However, in well-preserved habitats where road verges show a similar vegetation structure to surrounding areas, their role is still unknown. Road verges would have an important role as fine-scale connectivity providers for small mammals in a well-preserved habitat depending on land management on road surroundings. We aimed to quantify the effects of road verges and paved lanes on the fine-scale landscape connectivity for the wood mouse (Apodemus sylvaticus) in a well-preserved Mediterranean woodland. Additionally, we assessed the impact on connectivity of vegetation cutting on verges and of management in surrounding areas (i.e. firebreaks, grazing, ploughing and cork stripping). We quantified connectivity using graph theory based on two years of capture-recapture data. We compared a set of connectivity metrics (derived from the probability of connectivity index) in a road area and in a virtual roadless scenario. We found that the presence of the road reduced overall fine-scale landscape connectivity, acting as a partial barrier for wood mice movement. However, verges had a key role in promoting movement on road surroundings. Vegetation cutting on verges, and land ploughing in the surrounding landscape were the only management activities compromising connectivity. Our study supports the already known role of road verges as habitat corridors for small mammals. However, it goes beyond existing knowledge by quantifying the connectivity enhancement provided by road verges and demonstrating that this role is highly relevant even in well-preserved landscapes. Therefore, our findings emphasize the critical role of road verges and suggest important management options to enhance landscape connectivity for small mammals.

Companion Animal Owners' Knowledge, Attitudes and Perceptions Regarding Antibiotic Use in Portugal.

While multiple studies have focused on the motivations surrounding antibiotic prescription among veterinarians, little is known about companion animal owners' knowledge, attitude and perception (KAP) regarding the topic. A nationwide survey directed toward Portuguese dog and cat owners was conducted online and at veterinary practices to characterize their KAP regarding antibiotics. After database curation, a total of 423 valid submissions were considered. Although 97.9% of respondents stated that they knew what an antibiotic was, 23.5% and 19.2% answered that they were used to treat viral and fungal infections, respectively. Antimicrobial effectiveness was favored over cost when 87.7% of owners agreed they would prefer to spend more money to identify the appropriate antibiotic. Around 87% of respondents recognized antibiotic resistance as a significant health problem and 74.6% strongly agreed/somewhat agreed that antibiotic use in pets may contribute to resistance development. However, only 25.3% recognized that this could promote resistance dissemination, showing little awareness of the interconnection between human and animal health. Moreover, 55.6% of respondents were neutral when asked whether antibiotics used in veterinary medicine were also important for humans. These findings suggest that communication between veterinarians and pet owners can still be improved to further clarify the impact that antibiotic use has in pets from a One-Health perspective, also enabling antimicrobial stewardship interventions.

Cross-Sectional Study on the Prevalence and Factors Influencing Occurrence of Tick-Borne Encephalitis in Horses in Lithuania.

Various animal species have been evaluated in depth for their potential as Tick-borne encephalitis virus (TBEV) sentinel species, although evidence for equine capacity is incomplete. Therefore, a comprehensive cross-sectional stratified serosurvey and PCR analysis of selected horses (n = 301) were performed in TBEV endemic localities in Lithuania. Attached and moving ticks (n = 241) have been collected from aforementioned hosts to evaluate natural infectivity of TBEV vectors (Ixodes spp.) in the recreational environments surrounding equestrian centers. All samples were screened for TBEV IgG and positive samples were confirmed by virus neutralization test (VNT). 113 (37.5%) horses from all counties of Lithuania tested positive for TBEV IgG, revealing age and sex indifferent results of equine seroprevalence that were significantly dependent on pedigree: horses of mixed breed were more susceptible to infection possibly due to their management practices. TBEV prevalence in equine species corresponded to TBEV-confirmed human cases in the precedent year. As much as 3.9% of horses were viraemic with TBEV-RNA with subsequent confirmation of TBEV European subtype. 4/38 of tested tick pools were positive for TBEV-RNA (Minimal infectious rate 1.2%). Several unknown microfoci were revealed during the study indicating areas of extreme risk close to popular human entertainment sites. The study provides important evidence in favor of horses' usage as sentinel species, as equines could provide more detailed epidemiological mapping of TBEV, as well as more efficient collection of ticks for surveillance studies.

A continuous time version and a generalization of a Markov-recapture model for trapping experiments.

Wileyto et al. [E.P. Wileyto, W.J. Ewens, M.A. Mullen, Markov-recapture population estimates: a tool for improving interpretation of trapping experiments, Ecology 75 (1994) 1109] propose a four-state discrete time Markov process, which describes the structure of a marking-capture experiment as a method of population estimation. They propose this method primarily for estimation of closed insect populations. Their method provides a mark-recapture estimate from a single trap observation by allowing subjects to mark themselves. The estimate of the unknown population size is based on the assumption of a closed population and a simple Markov model in which the rates of marking, capture, and recapture are assumed to be equal. Using the one step transition probability matrix of their model, we illustrate how to go from an embedded discrete time Markov process to a continuous time Markov process assuming exponentially distributed holding times. We also compute the transition probabilities after time t for the continuous time case and compare the limiting behavior of the continuous and discrete time processes. Finally, we generalize their model by relaxing the assumption of equal per capita rates for marking, capture, and recapture. Other questions about how their results change when using a continuous time Markov process are examined.

Estimation of capture probabilities using generalized estimating equations and mixed effects approaches.

Modeling individual heterogeneity in capture probabilities has been one of the most challenging tasks in capture-recapture studies. Heterogeneity in capture probabilities can be modeled as a function of individual covariates, but correlation structure among capture occasions should be taking into account. A proposed generalized estimating equations (GEE) and generalized linear mixed modeling (GLMM) approaches can be used to estimate capture probabilities and population size for capture-recapture closed population models. An example is used for an illustrative application and for comparison with currently used methodology. A simulation study is also conducted to show the performance of the estimation procedures. Our simulation results show that the proposed quasi-likelihood based on GEE approach provides lower SE than partial likelihood based on either generalized linear models (GLM) or GLMM approaches for estimating population size in a closed capture-recapture experiment. Estimator performance is good if a large proportion of individuals are captured. For cases where only a small proportion of individuals are captured, the estimates become unstable, but the GEE approach outperforms the other methods.

The relationship between species detection probability and local extinction probability.

In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are <1 and that are heterogeneous among species. These methods can also be used to estimate community-dynamic parameters such as species local extinction probability and turnover rates (Nichols et al. Ecol Appl 8:1213-1225; Conserv Biol 12:1390-1398). Here, we present an ad hoc approach to estimating community-level vital rates in the presence of joint heterogeneity of detection probabilities and vital rates. The method consists of partitioning the number of species into two groups using the detection frequencies and then estimating vital rates (e.g., local extinction probabilities) for each group. Estimators from each group are combined in a weighted estimator of vital rates that accounts for the effect of heterogeneity. Using data from the North American Breeding Bird Survey, we computed such estimates and tested the hypothesis that detection probabilities and local extinction probabilities were negatively related. Our analyses support the hypothesis that species detection probability covaries negatively with local probability of extinction and turnover rates. A simulation study was conducted to assess the performance of vital parameter estimators as well as other estimators relevant to questions about heterogeneity, such as coefficient of variation of detection probabilities and proportion of species in each group. Both the weighted estimator suggested in this paper and the original unweighted estimator for local extinction probability performed fairly well and provided no basis for preferring one to the other.