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Road mortality can be a serious threat to different animals, including snakes. However, mortality patterns can vary between species, intraspecific groups, locations and time. We compared the number of road-killed individuals (carcasses) of two semiaquatic water snakes ( Natrix natrix and N. tessellata ) on 58 km of road sections bordered by an active floodplain and a flood-protected former floodplain on one side and mountainous areas on the other in NE Hungary based on surveys conducted once every two weeks in three non-consecutive years. The results showed high road mortality of snakes, with a spring and an autumn peak corresponding to the times when snakes emerge from and return to hibernating sites. The results show that small-scale spatial differences in road mortality were mediated by landscape structure along the road, while the effects of traffic volume, flood regime and the age and sex of the individuals were negligible. For conservation, the study suggests that establishing culvert passages under the road and/or artificial hibernating sites on the floodplain-side of the roads in critical sections can be promising in reducing road-related mortality., Competing Interests: The authors declare there are no competing interests., (©2024 Szabolcs et al.)

Roads are an important source of human economic progress, but also a threat to wildlife populations and natural habitats. Roads are responsible for the direct mortality of hundreds of millions of animals worldwide, with special negative effects for amphibians. Since the middle of the twentieth century, various types of mitigation measures have been constructed to reduce the negative effects of roads. However, despite the large availability of potential solutions designed for this purpose, there is still a knowledge gap about their effectiveness for amphibians. This study analysed whether permanent concrete drift fences reduced the roadkill risk for amphibians. We applied a before-after-control-impact (BACI) design in two road segments with concrete drift fences for amphibians. We recorded amphibians on these road segments three years before and three years after the fence installation. We further tested whether the presence of these mitigation measures transferred the animals to sites adjacent to the drift fences, creating new potential mortality aggregation sites (fence-end effect). Our results show a significant reduction in the number of amphibians reaching the sites with the drift fences. We were, however, unable to demonstrate the potential movement route transference, as our results were inconclusive. Despite the increase in amphibian numbers at the control sites in the first year after fence installation, the following two years presented similar amphibian numbers as the pre-fence years. We recognise the importance of permanent drift fences in reducing the mortality of amphibian populations; however, we encourage future studies to include tunnel-crossing data as well, to truly unveil the roadkill reduction power of amphibian mitigation measures, while maintaining or increasing connectivity between roadside habitats., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The surge in wildlife-vehicle collision research has not yet translated into a substantial decrease in animal fatalities. In line with the prevailing view, we suspect that drivers' behaviour may be the most crucial element. We address a research gap in drivers' attitudes towards and behaviour in response to wildlife-vehicle collisions from a tourist perspective. We designed a questionnaire to examine tourists' attitudes and behaviour in relation to wildlife-vehicle collisions while driving in Tasmania. We found that the respondents' sociodemographic attributes had minimal effect on their practical responses to roadkill. Tourists consider wildlife-vehicle collisions a serious problem for both biodiversity loss and animal welfare reasons, and their willingness to change their behaviour was high. However, many respondents did not stop to check for surviving pouch young. This inaction resulted either from overlooking the importance of pouch checking or a lack of knowledge on what action needed to be taken. There may also be a lack of understanding that roadkill left on the road leads to secondary roadkill incidents. Even though tourist behaviour does not automatically represent residents' behaviour, these findings will help to improve and tailor educational approaches to rectify the driver awareness/behaviour gap for both tourists and residents.

Road mortality adversely affects wildlife populations. As urbanization and infrastructure densities expand, transportation and wildlife management aim to mitigate wildlife-vehicle conflicts while conserving biodiversity. Roadways in aridland ecosystems can invariably and adversely impact wildlife differently from temperate and other biomes, yet these rapidly urbanizing regions are understudied as are urban-rural gradients. We conducted road-cruise surveys ( n = 204; 2018-2023) to assess anthropogenic, environmental, and temporal factors associated with vertebrate roadkill across the wildland-urban interface of Arizona's biodiverse Sonoran Desert ecoregion-already subjected to increased human development and climate change. Of n = 2019 vertebrates observed, 28.5% were roadkill. Increasing urbanization levels were associated with reduced vertebrate abundance on roads and increased road-killed endothermic vertebrates. Traffic volume was strongly associated with reduced vertebrate abundance and increased roadkill; additive effects on roadkill began at approximately 20 vehicles. Daily low temperature and/or relative humidity were also associated with roadkill across vertebrate groups. We provide empirical evidence to understand wildlife-roadkill associations across expanding wildland-urban interfaces to inform effective roadkill mitigation and wildlife conservation management strategies in biodiverse aridland regions. We recommend that managers mitigate or avoid development in rural areas that possess high biodiversity, valuable waterways or migration corridors, and populations of vulnerable species., Competing Interests: We declare we have no competing interests., (© 2024 The Author(s).)

The nine-banded armadillo (Dasypus novemcinctus) is currently considered an invasive species in parts of its range in the USA, and this range continues to expand to the north and east. Nine-banded armadillos are one of a handful of mammals known to contract leprosy (also known as Hansen's disease); range expansion thus leads to public health concerns about whether this might increase human exposure to infected animals. We collected blood samples from 61 road-killed armadillos over two summers (2021 and 2022) in Tennessee, a US state near the northern extreme of the species' current range, and screened them for exposure to Mycobacterium leprae, the causative agent of leprosy. All animals were seronegative, providing no evidence that range expansion is increasing the distribution of leprosy in the US., (© Wildlife Disease Association 2024.)

Roads are one of the most widespread structures that drive habitat loss and fragmentation. But they also restrict animal movement and drive landscape-level impacts on biodiversity. The South Pacific of Costa Rica is known for its high levels of biodiversity, but little has been done to reduce road impacts upon wildlife communities. To understand these impacts and advise on possible mitigation action, we used three key data approaches: 1. Camera traps, to survey wildlife activity along two major road sections that dissect the region's protected areas and biological corridors. Seventy-eight camera traps were deployed in secondary forest patches at different distances (between 200 m and 1 km) from the roads for six months and covariates were collected to explain the patterns found. 2. Citizen science data extracted from iNaturalist to identify roadkill "hotspots" along the roads. And 3. Circuitscape analysis, to assess how landscape structure could influence animal movement. Camera traps recorded 30 terrestrial species. Ocelots and agoutis displayed a negative effect of distance from protected area, while the Apex predators displayed a positive effect toward higher forest cover and vegetation density. Circuitscape analysis showed high connectivity throughout most of the area. Only a few locations showed higher flow (bottle neck locations), which coincided with roadkill "hotspots" identified through citizen science direct observations (70 observations of 21 species). Amalgamating data from the different analyses allow us to identify four key wildlife crossing locations (one of less priority) along the Inter-American Highway. We strongly recommend the placement of under/overpasses in these locations, with the aim to ensure wildlife safe movement and connectivity of wildlife populations in the region. Culvert modifications in the area could also be considered to incorporate wildlife underpasses at a reduced cost., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Osa Conservation reports financial support and equipment, drugs, or supplies were provided by Disney Worldwide Conservation Fund. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A commercial roadkill Virtual Fence (VF) mitigation device (iPTE Traffic Solutions) was used in a field trial to test its effectiveness, for which previously published results have been inconsistent, along a 4.9 km segment of road on Bruny Island, Tasmania. A total of 585 days of monitoring roadkill by species was conducted, with six sections that were alternatively switched on or off according to the Crossover and Multiple Before-After-Control-Impact (MBACI) experimental designs that divided monitoring into "off-on" then "on-off" periods. Aggregate counts, for each period by section combination, from daily counts of Tasmanian pademelons ( Thylogale billardierii ) were modelled, with a total count of 222. The statistical analysis used the MBACI design to estimate the VF effect using a log-odds ratio parameter (LORP) while accounting for local spatio-temporal effects. Both versions of the analysis, either averaged over the three spatial replicates (paired sections) or two temporal replicates (blocks), showed no statistically significant effect of the VF, judged as an LORP estimate not sufficiently below zero. Corresponding percentage reduction estimates of 9% and 16% were derived from the LORP. The corresponding statistical power required to detect a nominal significant reduction of 50% in rate was 0.5 and 0.6, respectively. This study confirms the results from a similar previous field trial in southern Tasmania that this VF is likely to lead to, if anything, only a minor reduction in roadkill.

Wildlife mortality due to collisions with vehicles (roadkill) is one of the predominant negative effects exerted by roads on many wildlife species. Reducing roadkill is therefore a major component of wildlife conservation. Roadkill is affected by various factors, including road attributes and traffic volume. It is theorized that the effect of traffic volume on roadkill probability should be unimodal. However, empirical evidence for this theory is lacking. Using a large-scale roadkill database of 18 wildlife species in Israel, encompassing 2846 km of roads over 10 years, we explored the effects of traffic volume and road attributes (e.g., road lighting, verge vegetation) on roadkill probability with a multivariate generalized linear mixed model. A unimodal effect of traffic volume was identified for the striped hyena (Hyaena hyaena), whereas 5 species demonstrated a novel quadratic U-shaped effect (e.g., golden jackal [Canis aureus]). Four species showed a negative linear effect (e.g., wild boar [Sus scrofa]). We also identified varying effects of road attributes on roadkill. For instance, road lighting and roadside trees decreased roadkill for several species, whereas bus stops and concrete guardrails led to increased roadkill. The theorized unimodal effect of traffic volume may only apply to large, agile species, and the U-shaped effect could be related to intraspecies variability in traffic avoidance behavior. In general, we found that both high-traffic and low-traffic roads can pose a high mortality risk for wildlife. It is therefore important to monitor roadkill on low-traffic roads and adapt road attributes to mitigate roadkill. Road design for effective roadkill mitigation includes reducing the use of concrete guardrails and median barriers where possible and avoiding dense bushes in verge landscaping. These measures are complemented by employing wildlife detection systems, driver warnings, and seasonal speed reduction measures on low-traffic roads identified as roadkill hotspots., (© 2024 The Authors. Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

High-speed railway (HSR) networks are rapidly expanding and are predicted to continue to grow over coming decades. However, there is scant knowledge of their environmental impacts. Their possible effects on bird mortality, particularly at viaducts, gives especial cause for concern. This work presents the results of a nine-month monitoring of bird activity in the vicinity of three HSR viaducts in Central Spain. The study focused on the effects of the infrastructure regarding bird frequentation of the site and on bird flight activity in the danger zone for collision with passing trains. The findings show (i) that bird communities may differ markedly between sites and (ii) that bird activity increases near the railway together with changes in relative species abundances. Furthermore, (iii) birds show a significant tendency to avoid flying across the danger zone, but (iv) all kinds of birds are at a real risk of collisions with trains at viaducts. The greatest danger is at viaduct extremes rather than in their central section, particularly during gusts of wind and for small or medium-sized birds. It also appears that relatively low viaducts might pose greater risk. In practical terms, these results (i) emphasise the need for thorough prior prospection of bird species present, and their flight patterns, where new viaducts are to be built, (ii) show that there is a real risk of bird collisions with trains at viaducts, which should be mitigated, with particular attention due to viaduct extremes and areas where their height is not much above the surrounding vegetation and (iii) strongly indicate the need to minimise viaduct features that may attract birds to them, for example as potential nest sites., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jesus Herranz reports financial support was provided by European Union. Juan E. Malo reports financial support was provided by Comunidad de Madrid Dirección General de Universidades e Investigación. Jesus Herranz reports financial support was provided by Comunidad de Madrid Dirección General de Universidades e Investigación. Juan E. Malo reports financial support was provided by European Union., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

We investigated roadkills in urban areas in Lithuania from 2007 to 2022, including two periods with COVID-19 restrictions on people's movement. We analyzed the proportions of wild and domestic animals in roadkill, annual trends, the predominant species involved, and monthly changes during the restrictions. Urban roads were characterized by a low species diversity of roadkilled mammals, with roe deer ( Capreolus capreolus ) dominating. Total numbers increased exponentially during the study period. The proportion of domestic animals, 12.2%, significantly exceeded that on non-urban roads in the country. The proportion of domestic animals decreased from over 40% in 2007-2009 to 3.7-5.4% in 2020-2022, while the proportion of wild mammals increased from 36.1-39.6% to 89.9-90.6%, respectively. During the periods of COVID-19 restrictions, the number of roadkills in urban areas was significantly higher than expected based on long-term trends. Compared to 2019, the number of roadkilled roe deer in 2020-2021 almost doubled from 700 to 1281-1325 individuals. These anthropause effects were, however, temporary. The imbalance between the roadkill number and transport intensity might require new mitigation strategies to sustain mammal populations in urban areas, at least through improving driver awareness on the issue.

The impact of COVID-19 restrictions on human and vehicular mobility on the number of roadkills of wild mammals, and roe deer in particular, was assessed in Lithuania. We statistically analyzed the distribution of all mammals and roe deer ( Capreolus capreolus ) as the most abundant species annually from 2002 to 2022 and monthly from 2020 to 2021, including during the two restriction periods. Notably, there was a marked decrease in roadkill incidents on main, national and regional roads, particularly in April-May 2020 (the beginning of lockdown period I) and November-December 2020 (the beginning of lockdown period II), 5.1-20.8% and 33.6-54.4%, respectively. During these months, collisions with mammals on the A14 main road were reduced by 75-90%. However, there was a significant increase in the number of roadkills in urban areas, resulting in the total number of mammal-vehicle and roe deer-vehicle collisions in 2020 and 2021 being higher than expected based on long-term trends. However, after restrictions were eased, collision numbers with wildlife on the main, national and regional roads increased again and became higher than expected.

Wildlife-vehicle collision (WVC) is one of the major causes of wildlife mortality and a concern for conservationists worldwide. The study of roadkill data that can be used to develop appropriate measures and strategies for both wildlife conservation and traffic safety to mitigate the WVC and animals' mortality. Extensive studies have been conducted in the developed countries on the identification of WVC hotspots and its potential impact; however, less attention is given in developing countries. Because of this, the problem is not well understood in developing countries. This study was intended to identify victim species, hotspot areas for roadkill, and factors that contribute to WVC in Jimma Zone, along three roads leading from Jimma City. Data were collected using a citizen science approach and a skilled man power road survey (March-September 2022) to document the number and type of species killed. Three road segments (135 km in total) were surveyed weekly as a baseline for future research. All statistical analyses were carried out using R-software. In the present study, a total of 84 roadkill specimens were collected from 16 different mammal species, of which 85.7% were medium-sized carnivores. The findings showed that Jackals ( Canis mesomalis and Canis adustus ) were the most frequently killed species (25%, n is 21), followed by Civettictis civetta (22.62%, n is 19). The study revealed that the major factors causing collisions include habitat type (forest cover) and wildlife behavior (nocturnal or diurnal). Further, the study revealed that the majority of WVC occurred at night (dusk) and at dawn in areas that are covered with dense forests. To minimize the potential risks of WVC and animals' mortality, we suggest putting warning signs in hotspot areas where roadkill usually occur frequently. In addition, we recommend creating awareness among drivers, traffic police, and all communities about the negative impacts and consequences of collisions on the ecological and economic value of wildlife., Competing Interests: The authors declare that they have no known competing financial or personal interests that could interfere with the work presented in this paper., (© 2023 The Authors.)

In this study, we conducted a retrospective survey of 63 giant anteaters ( Myrmecophaga tridactyla ) using the Federal University of Uberlândia, Minas Gerais State, Brazil as reference site for wild animals. We analyzed the clinical records of 63 animals from January 2016 to February 2020. The information obtained included the location where the anteater was found, the reason for rescue, estimated life stage, gender, weight, general condition of the animal, clinical signs, diagnosis, and destination. Of the 63 animals, 30.15%, (n = 19/63) were found in rural areas, 25.40% (n = 16/63) in urban areas, and 22.22% (n = 14/63) near highways. The main reason for rescue was run-over accidents (n = 18/63, 28.60%). Regarding life stage distribution, 27% (n = 17/63) were cubs, 25.40% (n = 16/63) were adolescent, and 41.26% (n = 26/63) were adults. There was a higher frequency of females (n = 35/63, 56%), and three (9%) of them were pregnant or had cubs. For injury evaluation, three of the 63 giant anteaters were dead on arrival at the rehabilitation site; therefore, we excluded them from this aspect of the study. Of the 60 remaining anteaters, only 13.33% (n = 8/60) of the animals were healthy upon physical examination.The most common condition was traumatic brain injury (n = 32/60 53.33%), followed by fractures (n = 23/60, 38.33%), neonate triad (n = 15/60, 25%), and abrasions (n = 15/60, 25%). The animals presented a high mortality rate (n = 39/60, 65%). The low number of giant anteaters reintroduced to their natural habitat and the high mortality rate of animals sent to rehabilitation centers show that the protection of giant anteaters is important to reduce the number of these animals sent to rehabilitation centers., Competing Interests: Conflict of interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

The rapidly growing global road networks put serious pressures on terrestrial ecosystems and increase the number and severity of human-wildlife conflicts, which in most cases manifest in animal-vehicle collisions (AVCs). AVCs pose serious problems both for biodiversity conservation and traffic safety: each year, millions of vertebrates are roadkilled globally and the related economic damage is also substantial. For a comprehensive understanding of factors influencing AVC it is essential to explore the human factor, that is, the habits and attitude of drivers; however, to date, comprehensive surveys are lacking on this topic. Here we addressed this knowledge gap and surveyed the habits of drivers and their experience and attitude towards AVCs by a comprehensive questionnaire covering a large geographical area and involving a large number of respondents (1942 completed questionnaires). We aimed to reveal how driving habits affect the chance of AVC, and explored the attitude of the drivers regarding AVC. We found that the number of lifetime AVC cases was higher for male drivers, for those who drove longer distances per year, had more driven years, used country roads or drove large vehicles. Our results showed that almost half of the drivers surveyed had experienced at least one AVC in their lifetime. Drivers' attitudes towards the importance of nature conservation or traffic safety in the aspect of AVC, and fear of collision showed a significant correlation with experienced AVC cases. Drivers' opinions indicated that the most trusted and desired AVC prevention measures were physical objects such as fences and wildlife crossings. Our research provides guidelines for developing targeted initiatives in the future to increase awareness about the significance of AVC and target those drivers who are most vulnerable to AVC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In light of rapidly expanding road networks worldwide, there is increasing global awareness of the growing amount of mammalian roadkill. However, the ways in which road mortality affects the population dynamics of different species remains largely unclear. We aimed to categorise the demographic parameters in mammalian populations around the world that are directly or indirectly affected by road mortality, as well as identify the most effective study designs for quantifying population-level consequences of road mortality. We conducted a comprehensive systematic review to synthesise literature published between 2000 and 2021 and out of 11,238 unique studies returned, 83 studies were retained comprising 69 mammalian species and 150 populations. A bias towards research-intensive countries and larger mammals was apparent. Although searches were conducted in five languages, all studies meeting the inclusion criteria were in English. Relatively few studies (13.3%) provided relevant demographic context to roadkill figures, hampering understanding of the impacts on population persistence. We categorised five direct demographic parameters affected by road mortality: sex- and age-biased mortality, the percentage of a population killed on roads per year (values up to 50% were reported), the contribution of roadkill to total mortality rates (up to 80%), and roadkill during inter-patch or long-distance movements. Female-biased mortality may be more prevalent than previously recognised and is likely to be critical to population dynamics. Roadkill was the greatest source of mortality for 28% of studied populations and both additive and compensatory mechanisms to roadkill were found to occur, bringing varied challenges to conservation around roads. In addition, intra-specific population differences in demographic effects of road mortality were common. This highlights that the relative importance of road mortality is likely to be context specific as the road configuration and habitat quality surrounding a population can vary. Road ecology studies that collect data on key life parameters, such as age/stage/sex-specific survival and dispersal success, and that use a combination of methods are critical in understanding long-term impacts. Quantifying the demographic impacts of road mortality is an important yet complex consideration for proactive road management., (© 2023 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

Animal-vehicle collisions (AVC) threaten animals as well as human life and property. AVC with ungulates, called ungulate-vehicle collision (UVC), often seriously endangers human safety because of the considerable body size of ungulates. In the Republic of Korea, three ungulate species, Capreolus pygargus , Hydropotes inermis , and Sus scrofa , account for a large proportion of AVC. This study aimed to understand the characteristics of UVC by examining various parameters related to habitat, traffic, and seasonality using MaxEnt. The results showed that the peak UVC seasons coincided with the most active seasonal behaviors of the studied ungulates. For the modeling results, in C. pygargus , habitat variables are most important for models across seasons, and UVC events are most likely to occur in high mountain chains. In H. inermis , habitat and traffic variables are most important for models across seasons. Although the important habitat for the models were different across seasons for S. scrofa , the maximum speed was consistently critical for models across all seasons. Factors critical to UVC in the Republic of Korea were different for the three ungulate species and across seasons, indicating that seasonal behavior should be considered along with landscape and traffic characteristics to mitigate UVC.

Roadkill and landscape composition affect snakes at different spatial scales, depending on the functional trait value of the species, which is reflected in the functional diversity indices at the assemblage level. This study evaluated the effect of roads and landscape composition on snakes' functional diversity at different areas of influence (250, 500, 1000, and 2000 m buffer areas). We compared roadkill snake species with those assemblages inhabiting the adjacent vegetation in the Orinoco region, Colombia. We surveyed snakes using transects on the road and adjacent areas on 13 landscapes along the road. We evaluated the effect of 16 landscape metrics at six land cover classes on the snake's functional diversity at four different areas of influence (from 250 to 2000 m around the sampled sites). The functional redundancy index was higher for roadkill species, suggesting that roads eliminate species that play similar roles in the assemblage and ecosystem processes. Likewise, the low values of functional redundancy in the adjacent vegetation call attention to the fact that each species surviving in this transformed landscape has a crucial active role in ecosystem processes in snake assemblages. For roadkill snakes, forest metrics explained changes in functional richness and functional evenness at a 250 m area of influence. In comparison, transient crop and pasture metrics explained changes in functional evenness and divergence at 2000 m. For snakes inhabiting the adjacent vegetation, the cohesion of pasture explained changes in functional richness at 250 m, and forest metrics explained changes in functional redundancy and evenness at 2000 m. Anthropogenic landscape transformation may have a greater effect on snake functional diversity at local scales than roadkill. In savanna ecosystems, the presence of native forest at 2000 m radius around roads promotes the conservation of snake assemblages. However, within a 250 m radius, the risk of snake roadkill increases when the road borders native forest. Therefore, it is necessary to implement wildlife crossing in these sections of the road., Competing Interests: The authors declare that there are no potential conflicts of interest concerning this article's research, authorship, and publication., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Monitoring the presence and distribution of alien species is pivotal to assessing the risk of biological invasion. In our study, we carried out a worldwide review of roadkill data to investigate geographical patterns of biological invasions. We hypothesise that roadkill data from published literature can turn out to be a valuable resource for researchers and wildlife managers, especially when more focused surveys cannot be performed. We retrieved a total of 2314 works published until January 2022. Among those, only 41 (including our original data) fitted our requirements (i.e., including a total list of roadkilled terrestrial vertebrates, with a number of affected individuals for each species) and were included in our analysis. All roadkilled species from retrieved studies were classified as native or introduced (domestic, paleo-introduced, or recently released). We found that a higher number of introduced species would be recorded among roadkill in Mediterranean and Temperate areas with respect to Tropical and Desert biomes. This is definitely in line with the current knowledge on alien species distribution at the global scale, thus confirming that roadkill datasets can be used beyond the study of road impacts, such as for an assessment of different levels of biological invasions among different countries.

Wildlife-vehicle collisions (WVCs) cause millions of vertebrate mortalities globally, threatening population viability and influencing wildlife behaviour and survival. Traffic volume and speed can influence wildlife mortality on roads, but roadkill risk is species specific and depends on ecological traits. The COVID-19 pandemic, and associated UK-wide lockdowns, offered a unique opportunity to investigate how reducing traffic volume alters WVC. These periods of reduced human mobility have been coined the 'anthropause'. We used the anthropause to identify which ecological traits may render species vulnerable to WVC. We did this by comparing the relative change in WVC of species with differing traits before and during the anthropause. We used Generalised Additive Model predictions to assess which of the 19 species most frequently observed as WVC in the UK exhibited changes in road mortality during two lockdown periods, March-May 2020 and December 2020-March 2021, relative to the same time periods in previous years (2014-2019). Compositional data analysis was used to identify ecological traits associated with changes in the relative number of observations during lockdown periods compared to previous years. WVC were, across all species, 80% lower during the anthropause than predicted. Compositional data analysis revealed proportionally fewer reports of nocturnal mammals, urban visitors, mammals with greater brain mass and birds with a longer flight initiation distance. Species that have several of these traits, and correspondingly significantly lower than predicted WVC during lockdowns, included badgers Meles meles, foxes Vulpes vulpes, and pheasants, Phasianus colchicus; we posit they stand to benefit most from reduced traffic, and, of the species studied here, have highest mortality under 'normal' traffic levels. This study identifies traits and species that may have experienced a temporary reprieve during the anthropause, and highlights the impacts of traffic-induced mortality on species numbers and ultimately on trait frequency in a road-dominated landscape. By taking advantage of reductions in traffic offered by the anthropause, we can understand how vehicles influence wildlife survival and behaviour and may be exerting a selective force for certain species and traits., (© 2023 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Smooth-coated otters ( Lutrogale perspicillata ) were transient in Singapore before one resident family group was observed in 1998, presumably having recolonized from Peninsular Malaysia. A population survey in 2017 revealed a minimum of 11 groups and 79 individuals. Since then, movements of otter groups within urban areas have led to increasing numbers of human-otter encounters, including conflicts. We determined the current abundance, population structure, and distribution of smooth-coated otters in Singapore. We assessed seven sampling zones nationwide through verified sighting records and social media. Mortality records from 2019 to 2021 were sourced from the Otter Working Group and Wildlife Reserves Singapore. In early 2021, there were a minimum of 17 groups and 170 individuals. Groups ranged from 2 to 24 individuals. Smooth-coated otters occupy coastal areas, waterways, reservoirs, and sites within the city center in urban gardens and ponds. Following territorial conflicts at waterways, smooth-coated otter groups moved into the urban matrix. Vehicle collisions are the main cause of mortality and are frequent at dams separating freshwater and coastal habitats. While there is a clear increase in smooth-coated otter numbers since 2017, there remain multiple natural and human-caused threats to otter persistence., Competing Interests: The authors have no conflicts of interest to declare., (© The Author(s) 2023. Published by Oxford University Press on behalf of the American Society of Mammalogists.)

For several species, roadkill is not spatially aggregated on hotspots, having instead a more diffuse pattern along the roads. For such species, management measures such as road passages may be insufficient for effective mitigation, since a large part of the road crossings is likely to occur outside the influence of those structures. One complementary approach could be to implement temporary mitigation actions, such as traffic calming. This requires understanding when roadkill peaks may occur. We tested the feasibility of predicting seasonal peaks of roadkill using data from a 3-year systematic monitoring (78 surveys over ca. 960 km of roads) from eight non-flying vertebrate species from Mato Grosso do Sul, Brazil, with different body size and life history traits (ca. 6400 records from focal species). We modelled the time-series of the roadkill of these species at large scale (state level) using generalized additive mixed models (GAMMs). We used the data of the first 2 years as training datasets, and the information from the third year of surveys as testing datasets to evaluate the prediction performance of models. Overall, the models of species feed with a higher number of records were able to follow reasonably well the variations of roadkill over time, although they were not able to correctly predict the number of collisions. For species with fewer observations, the models presented a poorer goodness-of-fit and prediction ability. Our results suggest that, at least for those species with higher roadkill rates, it can be possible to forecast periods of higher probability of occurring hot-moments of mortality. Such models can provide valuable information to implement seasonal management actions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Motor vehicle collisions (MVCs) are a severe threat to wildlife biodiversity worldwide and most vertebrate species are at risk. However, there is a considerable knowledge gap on the traumatic features and potential patterns of MVCs in wildlife. We investigated traumatic injuries (TIs) caused by MVCs (MVCs-TIs) in 430 neotropical wild mammals representing 44 species from Brazil. Injuries were classified topographically into four categories: abdomen/pelvis (AP), chest (TX), head/neck (HN) and extremities (EX). We also determined the prevalence of pathological changes in MVC fatalities. AP (n = 381; 89%) was the most affected body segment, followed by TX (n = 372; 87%), HN (n = 363; 84%) and EX (n = 288; 67%). The most prevalent gross pathological findings were single or multiple bone fractures (n = 397; 92%), visceral organ rupture (n = 371; 86%), haemothorax (n = 220; 51%) and pulmonary haemorrhage (n = 212; 49%). Microscopically, pulmonary oedema (n = 324; 82%) and haemorrhage (n = 272; 69%) were the most prevalent lesions. No distinct TI patterns were evident across the various taxonomic groups, although trends were found in some taxa, such as armadillos. These results may help clinicians performing emergency care on MVC wildlife patients and may be of value in pathological and forensic investigations where a MVC has been deemed a likely contributory factor to death., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Roads may influence the selection of phenotypic traits of wildlife. In particular, the likelihood of vehicle collisions with wildlife may vary depending on body coloration in contrast to the road, which may be exaggerated by cultural attitudes toward the species. The timber rattlesnake Crotalus horridus is a threatened species that varies widely in coloration, and their color pattern could influence thermoregulatory use of roads and visibility to motorists. Moreover, better-camouflaged snakes may have higher road mortality in areas where environmental interest is lower and, perhaps, negative attitudes toward wildlife are more prevalent. We used citizen scientist observations of timber rattlesnakes from iNaturalist and categorized for each rattlesnake the surface they were on, its color pattern, and whether they were alive. We combined iNaturalist data with Google Trends data to characterize regional variation in environmental interest. We discovered that lighter-colored snakes were more likely to be found on roads, as were snakes further south, west, and on warmer days. Once on a road, coloration did not influence survival regardless of road type or environmental interest. However, snakes on asphalt roads or on southern roads were more likely to be found dead. The higher likelihood of lighter-colored snakes being found on roads suggests that they are at a greater overall risk of road death, potentially selecting for darker coloration. Citizen scientist behavior may at least partly underlie the influence of latitude on the results, however, and further work in the application of citizen science data to such research questions is warranted., Competing Interests: The authors have no conflict of interest to declare., (© The Author(s) 2022. Published by Oxford University Press on behalf of Editorial Office, Current Zoology.)

The roadkill of wildlife is a global problem. Much has been written about deterring wildlife from roads, but, as of yet, there is no empirical support for deterrents based on visual and/or auditory signals. A recent paper entitled 'Can virtual fences reduce wombat road mortalities?'reported the results of a roadkill mitigation trial. The authors installed a 'virtual fence' system produced by iPTE Traffic Solutions Ltd. (Graz, Austria) and evaluated its effectiveness for reducing roadkills of bare-nosed wombats ( Vombatus ursinus ) in southern Australia. The authors recorded roadkills in a simple Before-After-Control-Impact design but did not conduct any formal statistical analysis. They also measured three contextual variables (vegetation, wombat burrows, and vehicle velocity) but did not link these to the occurrence of roadkills in space and time. The authors concluded that the iPTE virtual fence system was 'minimally effective', yet 'appears promising'. Our analysis of their data, using standard inferential statistics, showed no effect of the virtual fence on roadkills whatsoever. We conclude that the iPTE system was not effective for mitigating the roadkills of bare-nosed wombats.

Background: Species of Plasmodium (Haemosporida, Plasmodiidae) are remarkably diverse haemoparasites. Information on genetic diversity of avian malaria pathogens has been accumulating rapidly, however exo-erythrocytic development of these organisms remains insufficiently addressed. This is unfortunate because, contrary to Plasmodium species parasitizing mammals, the avian malaria parasites undergo several cycles of exo-erythrocytic development, often resulting in damage of various organs. Insufficient knowledge on the exo-erythrocytic development in most described Plasmodium species precludes the understanding of mechanisms of virulence during avian malaria. This study extends information on the exo-erythrocytic development of bird malaria parasites., Methods: A roadkill fieldfare (Turdus pilaris) was sampled in Switzerland and examined using pathologic, cytologic, histologic, molecular and microbiologic methods. Avian malaria was diagnosed, and erythrocytic and exo-erythrocytic stages of the parasite were identified using morphologic characteristics and barcode DNA sequences of the cytochrome b gene. The species-specific characteristics were described, illustrated, and pathologic changes were reported., Results: An infection with Plasmodium matutinum lineage pLINN1 was detected. Parasitaemia was relatively low (0.3%), with all erythrocytic stages (trophozoites, meronts and gametocytes) present in blood films. Most growing erythrocytic meronts were markedly vacuolated, which is a species-specific feature of this parasite's development. Phanerozoites at different stages of maturation were seen in leukocytes, macrophages, and capillary endothelial cells in most organs examined; they were particularly numerous in the brain. Like the erythrocytic meronts, growing phanerozoites were markedly vacuolated. Conspicuous exo-erythrocytic development and maturation in leucocytes suggests that this fieldfare was not adapted to the infection and the parasite was capable to escape from cellular immunity., Conclusions: This is the first report of exo-erythrocytic development of the malaria parasite lineage pLINN1 during single infection and the first report of this lineage in the fieldfare. The findings of multiple phanerozoites in brain, skeletal muscle, and eye tissue in combination with signs of vascular blockage and thrombus formation strongly suggest an impaired vision and neuromuscular responsiveness as cause of the unexpected collision with a slowly moving car. Further studies on exo-erythrocytic stages of haemosporidian parasites are pivotal to understand the true level of populational damage of avian malaria in wild birds., (© 2022. The Author(s).)

We previously showed that registration efforts and traffic intensity explain 90% of variation in mammal roadkill numbers, 70% of variation in the numbers of recorded species and 40% of diversity variation. Here we analyze semiaquatic mammal roadkill in Lithuania in 2002-2021, relating these to the monitoring effort. From 39,936 analyzed roadkill, the European beaver ( Castor fiber ) was registered 60 times, American mink ( Neovison vison ) 26 times, otter ( Lutra lutra ) 22 times and muskrat ( Ondatra zibethica ) 3 times. The average roadkill indexes were 0.000065, 0.00076, 0.00061 and 0.00010 ind./km/day, and the extrapolated annual roadkill for the country was 44-357, 36-456, 49-464 and 89-144 individuals, respectively. Beaver roadkill numbers correlated with the registration effort and traffic intensity, otter roadkill with registration effort only and mink with hunting bag (number of hunted individuals per year). Roadkill was not always related to proximity to water, with 38-54% of roadkill occurring over 200 m from the nearest water source. With American mink and muskrat being invasive species in the EU and otter protected in many countries, it is valuable to enhance the registrations of their roadkill (using targeted efforts by drivers, hunters or other citizen scientists) to obtain the extrapolated amount of roadkill and to use this knowledge in species management.

Landscape transformation favors the spread of new pathogens that can be shared between domestic and wild animals. Certain adenoviruses (e.g., canine adenovirus 1 and 2, family Adenoviridae) can infect domestic and wild carnivores. In domestic canids, these viruses are associated with hepatic and respiratory diseases (among others). Nevertheless, information regarding adenovirus pathogenicity and molecular features in wild carnivores is still limited. Herein we surveyed adenovirus in free-ranging carnivores from Brazil. Total DNA was extracted from and subsequently tested by a nested panPCR in spleen and/or lung of 52 carnivores, representing species of the following families: Canidae (n = 4), Felidae (n = 3), Mustelidae (n = 2) and Procyonidae (n = 2). The obtained sequences were compared to others available at GenBank. Available tissue samples from the positive cases were evaluated histopathologically. One out of 52 (1.9%, CI 95%, 0.0-5.7%) carnivores was positive; a roadkilled ocelot (Leopardus pardalis). The obtained sequence presented a low deduced amino acid (78.1%) similarity with the closest adenovirus, identified in a pinniped from the United States of America. This fact and its detection in a novel host suggest it may be representative of a novel species and denominated ocelot adenovirus 1. None of the gross and microscopic findings of the positive case were associated with adenovirus. To the authors' knowledge, this is the first report of adenovirus in wild felids of South America and the second worldwide. Further studies are necessary to assess the epidemiology and potential pathogenicity of this agent in wild carnivores., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Amphibians and reptiles are the most threatened vertebrates by traffic, especially near ponds and wetlands. The main aim of this study was to examine seasonal and spatial patterns of amphibian and reptile road mortality in Special Nature Reserve "Obedska bara" (Serbia). We chose a road section of 4.2 km near the largest wetland in Serbia, with two different habitat types (forest-pond and agricultural area-pond). During 2018 (32 fieldwork days) and 2019-2020 (three control fieldwork days), we found 20,457 and 2231 road-killed animals, respectively. We recorded nine amphibian and eight reptile species. Amphibians (93%) were more vulnerable to traffic than reptiles (7%). The number of killed amphibians and reptiles varied between the seasons. Generally, amphibian roadkill was most frequent during the summer, whereas reptile roadkill was most frequent in spring and at the end of the summer. Furthermore, different roadkill patterns were observed during the examined months. In addition, we found that habitat type significantly affects the vulnerability of animals towards the roads. For both amphibians and reptiles, there were significant aggregations of roadkill, and most hotspots were located at the forest pond habitat type where mitigation measures must be applied (construction of tunnels and fences).

Most primate populations are declining; 60% of species face extinction. The expansion of transportation and service corridors (T&S) (i.e., roads and railways and utility and service lines) poses a significant yet underappreciated threat. With the development of T&S corridors predicted to increase across primates' ranges, it is necessary to understand the current extent of its impacts on primates, the available options to mitigate these effectively, and recognize research and knowledge gaps. By employing a systematic search approach to identify literature that described the relationship between primates and T&S corridors, we extracted information from 327 studies published between 1980 and 2020. Our results revealed that 218 species and subspecies across 62 genera are affected, significantly more than the 92 listed by the IUCN Red List of Threatened Species. The majority of studies took place in Asia (45%), followed by mainland Africa (31%), the Neotropics (22%), and Madagascar (2%). Brazil, Indonesia, Equatorial Guinea, Vietnam, and Madagascar contained the greatest number of affected primate species. Asia featured the highest number of species affected by roads, electrical transmission lines, and pipelines and the only studies addressing the impact of rail and aerial tramways on primates. The impact of seismic lines only emerged in the literature from Africa and the Neotropics. Impacts are diverse and multifaceted, for example, animal-vehicle collisions, electrocutions, habitat loss and fragmentation, impeded movement and genetic exchange, behavioral changes, exposure to pollution, and mortality associated with hunting. Although several mitigation measures were recommended, only 41% of studies focused on their implementation, whereas only 29% evaluated their effectiveness. Finally, there was a clear bias in the species and regions benefiting from research on this topic. We recommend that government and conservation bodies recognize T&S corridors as a serious and mounting threat to primates and that further research in this area is encouraged., (© 2021 Society for Conservation Biology.)

In times of massive biodiversity loss and ongoing environmental crises, it is extremely important to ensure long-term conservation efforts of threatened species like Eurasian otters ( Lutra lutra ). To gain insights into the status of Northern Germany's otter population, 92 otters found dead in Schleswig-Holstein between 2015-2020 were collected and underwent detailed dissection with the aim to establish a monitoring program for this population. Examinations followed a protocol especially designed for otters, including various biological data assessments and extended sampling. The finding sites showed a clear concentration in the Continental region. Seasonal concentration differed among the years, yet peaks were seen from fall to winter. Overall, more males than females were found, although this differed among the years. The majority of otters that could be aged were between 1-3 years. Placental scars and pregnancy were recorded in only few females. Nutritional status was good in most cases. Infectious diseases found included Vagococcus lutrae , Toxoplasma gondii , and Emmonsia spp. A major cause of death was roadkill. Known sample bias in studies focusing on roadkill was considered in the finding interpretation. Continuation of the population health investigations is mandatory to analyze potential trends and to establish an actual monitoring program for Eurasian otters in Schleswig-Holstein.

Background: To avoid the uncontrolled spread of COVID-19 in early 2020, many countries have implemented strict lockdown measures for several weeks. In Austria, the lockdown in early spring has led to a significant drop in human outdoor activities, especially in road traffic. In Project Roadkill, a citizen science project which aims to collect data on road-killed animals, we observed a significant decrease in reported roadkills., Methods: By asking the citizen scientists through a survey how their travelling routines were affected, we investigated if the observed decrease in roadkills was grounded in less animals being killed by traffic, or in citizen scientists staying at home and thus reporting less road-killed animals., Results: A majority of the respondents stated that they felt to have reported less roadkills during the lockdown, regardless if they changed their travelling routine or not. This observation in combination with the overall decrease in road traffic indicates that fewer animals were killed during the lockdown. We conclude that when analyzing citizen science data, the effects of lockdown measures on reporting behaviour should be considered, because they can significantly affect data and interpretation of these data., Competing Interests: The authors declare that they have no competing interests., (© 2021 Dörler and Heigl.)

Vehicles collide with hundreds of thousands of deer on European roads each year. This leads to animal deaths and suffering, economic damage and risks for human safety, making the reduction of road mortality a major field in conservation biology. In order to successfully reduce roadkill, we need improved knowledge regarding spatio-temporal patterns of deer-vehicle collisions (DVCs) on a landscape scale. Here, we analyzed >85,000 DVCs collected over 17 years in Denmark to investigate changes in the number of DVCs over time and to find spatio-temporal patterns of DVC occurrence. We used a use-availability design - originally developed for habitat selection analyses - to compare DVCs involving roe deer (Capreolus capreolus), red deer (Cervus elaphus) and fallow deer (Dama dama) with random road locations on a landscape scale. This approach enabled us to combine temporal (seasonal and diel variation), spatial (land cover, road density and type) and other relevant variables (deer population density, traffic, and deer activity) within the same analysis. We found that factors related to infrastructure and land cover were most important in explaining patterns of DVCs, but seasonal and diel changes, deer activity, and population density were also important in predicting the occurrence of DVCs. Importantly, patterns of DVCs were largely similar between the three deer species, with more DVCs occurring at intermediate traffic density, increasing forest cover, during dusk and dawn, and with increasing deer activity and population density. The strong and consistent patterns found here will allow the development of flexible mitigation measures. We propose that our findings could be used to develop a spatio-temporally flexible warning system for smartphones and navigation systems that is based on existing map providers, making it a widely available and cheap mitigation measure., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Accurate information provided by reliable models is essential for identifying hotspots and mitigating roadkill. However, existing methods, such as kernel density estimation (KDE) and maximum entropy modeling (ME) may individually identify only a subset of the suitable locations for mitigation, because KDE cannot detect hotspots once local abundances are depressed, and ME may only partially identify current hotspots due to imperfect discrimination skill. Here, we propose a hybrid consensus modeling (HCM) approach that leverages the strengths of both KDE and ME by using their consensus to identify the core subset of hotspots. We collected herpetofauna (amphibians and reptiles) roadkill data (N = 839) along four roads in Taiwan (R.O.C.) to evaluate the statistical performance and theoretical mitigation efficiency of HCM, KDE and ME, and to compare the allocation among roads, spatial clustering, and environmental conditions in the identified hotspots. HCM was applied on the herpetofauna dataset as well as separately on amphibians and reptiles. Although the discrimination skill of KDE and ME models for both target clades together was good to excellent (AUC KDE  = 0.944, AUC ME  = 0.822), the highest theoretical mitigation efficiency, was displayed by HCM Consensus (2.89), followed by KDE (2.58), and ME (1.91). Furthermore, we show that theoretical mitigation efficiency increases with decreasing spatial clustering (Moran's I). Given pervasive budget constraints, we recommend to limit permanent mitigation measures such as fenced culverts to HCM Consensus hotspots, temporary measures to KDE hotspots, and to target additional monitoring at ME hotspots., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

High traffic volume is one of the main contributors to wildlife-vehicle collision (WVC) and wildlife mortality on roads. Government shelter-in-place (SIP) orders have been used to help mitigate the spread of COVID-19, resulting in unprecedented reductions in global traffic volumes. Using traffic and collision data from four US states (California, Idaho, Maine, and Washington), we investigated changes in total WVC, following the state and local SIP orders. From mid-March to mid-April 2020, these orders have resulted in up to 71%, 63%, 73%, and 72% reduction in driving, as measured by vehicle miles traveled (VMT), in CA, ID, ME, and WA respectively. The daily WVC rates from the 4 weeks prior to SIP orders going into effect, to the 4 weeks after, declined 34%, with 21, 36, 44, and 33% declines for CA, ID, ME, and WA, respectively. For mountain lions ( Puma concolor) in CA, there was a 58% decline in mortality during the traffic reduction. The changes in WVC from 1 month pre-SIP orders to 1 month post-order only occurred in 2020 and not 2015, 2016, 2017, 2018, or 2019, suggesting that the reductions were associated with the reductions in traffic. The measured declines in WVC reversed in ME and WA during May, June and July 2020, paralleling reversals in traffic volumes. A 34% reduction in WVC would potentially equate to 10s of millions fewer vertebrates killed on US roadways during one month of traffic reduction, representing an unintentional conservation action unprecedented in modern times., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Elsevier Ltd. All rights reserved.)

Fences have been widely implemented to reduce the risk of wildlife-vehicle collisions, wildlife disease spread, and crop damage. To manufacture fences, it is imperative to assess the behavioural responses of the target species. Here, we investigated the success rate of fences and classified eight behavioural responses of Korean water deer ( Hydropotes inermis argyropus ) to different fence heights. We explored the association of 801 behavioural responses and defined a threshold based on 40 events by applying non-metric multidimensional scaling and a binary logistic generalised linear mixed model. With fences lower and higher than 1.2 m, recession and rest were the dominant behaviours, respectively, before the deer crossed the fences by performing vertical and running jumps. Considering all independent events, 0.9 m was the marginal threshold, with highly variable outliers over this value. Placing exit pathways for deer and eliminating possible resting areas outside fences are essential for reducing the number of successful jump attempts. The optimal fence height could differ based on conditional factors; however, we recommend a height of 1.5 m considering the cost and roadkill risk. In conclusion, exploring and classifying the behavioural responses of the target species may be critical for establishing appropriate fence protocols.

Globally, wildlife is affected by unprecedented changes related to the COVID-19 pandemic. In this paper, the lockdown effect on the traffic-related mortality in hedgehogs in an urban area was studied. Comparing the pre-pandemic (2018 and 2019) and pandemic (2020) years, we showed that hedgehog roadkill levels during the lockdown period were over 50% lower (which means a decrease greater than the decrease in road traffic in the same period measured by the number of accidents or the average number of vehicles per day). Based on literature data, we showed that this may mean at least tens of thousands of hedgehogs have survived on a national scale. We report the need to start intensive research on the possible demographic and genetic effects of this unique phenomenon. We also ask how stable the effect of the COVID-19 pandemic will be on wildlife and whether the lockdown (which is an anthropause) may reverse the negative trends in the decline in the number of wild species, including hedgehogs.

In a context of ongoing biodiversity erosion, obtaining genomic resources from wildlife is essential for conservation. The thousands of yearly mammalian roadkill provide a useful source material for genomic surveys. To illustrate the potential of this underexploited resource, we used roadkill samples to study the genomic diversity of the bat-eared fox ( Otocyon megalotis ) and the aardwolf ( Proteles cristatus ), both having subspecies with similar disjunct distributions in Eastern and Southern Africa. First, we obtained reference genomes with high contiguity and gene completeness by combining Nanopore long reads and Illumina short reads. Then, we showed that the two subspecies of aardwolf might warrant species status ( P. cristatus and P. septentrionalis ) by comparing their genome-wide genetic differentiation to pairs of well-defined species across Carnivora with a new Genetic Differentiation index (GDI) based on only a few resequenced individuals. Finally, we obtained a genome-scale Carnivora phylogeny including the new aardwolf species., Competing Interests: RA, MT, CS, NA, AK, EC, BN, FD No competing interests declared, (© 2021, Allio et al.)

Roadkill estimates for different species and species groups are available for many countries and regions. However, there is a lack of information from tropical countries, including from Latin America. In this study, we analyzed medium and large-sized mammal roadkill data from 18 toll road companies (TRC) in São Paulo State (6,580 km of monitored toll roads), Brazil. We extrapolated these roadkill numbers to the entire system of major paved roads in the State (36,503 km). The TRC collected mammal-road- mortality data both before (2-lanes) and after (4-lanes) road reconstruction. We used the "before" data from the TRC to estimate annual mammal-road-mortality along 2-lane roads that remained public roads. Combined with the data for the new 4-lane highways, this allowed us to estimate annual mammal road mortality for all the paved roads in the State. During 10 years of roadkill monitoring along toll roads, a total of 37,744 roadkilled mammals were recorded, representing a total of 32 medium to large-sized mammal species (average number of roadkilled individuals/year = 3,774 ± 1,159; min = 1,932; max = 5,369; 0.6 individuals roadkilled/km/year). Most roadkilled species were common generalists, but there were also relatively high roadkill numbers of threatened and endangered species (4.3% of the data), which is a serious conservation concern. Most of the roadkill was reported occurred during the nocturnal period (66%, n = 14,189) and in the rainy months (October-March) (55%, n = 15,318). Reported mammal roadkill tended to increase between 2009 and 2014 (R 2 = 0.614; p = 0.065), with an average increase of 313.5 individuals/year. Extrapolation of the results to the entire São Paulo State, resulted in an average estimate of 39,605 medium and large-sized mammals roadkilled per year. Our estimates of the number of roadkilled individuals can be used as one of the input parameters in population viability analyses to understand the extinction or extirpation risk, especially for threatened and endangered species., Competing Interests: The authors declare no conflict of interest., (© 2021 Published by Elsevier Ltd.)

Many approaches have been developed in order to mitigate wildlife-vehicle collisions (WVC), their causes and consequences. Reliable data on the amount and location of killed animals along roads are therefore necessary. The existing WVC databases are usually, however, far from complete. This data underreporting causes problems when identifying the riskiest places along a transportation infrastructure. WVC data underreporting can distort the results of WVC hotspots determination. In this work, we simulated WVC hotspots identification and stability under various rates of WVC data underreporting. Our aim was to investigate whether WVC hotspots can be found at the original locations even when data are strongly underreported. We applied the KDE + method for WVC hotspots identification. The KDE + method also allows for hotspots ranking according to cluster strength and collective risk. These two measures were then used for detection of diminishing hotspot signals with a rising level of underreporting. We found that WVC hotspots with a greater cluster strength suffered less from underreporting whereas hotspots will lower values of both cluster strength and collective risk were not detected when underreporting in the data increased. Hotspots with a cluster strength above 0.5 were almost always detected when data underreporting remained below 50%. More than 50% of these hotspots (with cluster strength above 0.5) were detectable even when underreporting rate was between 50 and 80%. We further studied the effects of both spatial and temporal underreporting. Whereas temporal change of underreporting was not a problem in hotspots detection, spatial underreporting introduced significant errors producing both false positive and false negative results (hotspots). We conclude that both researchers and practitioners should be aware of the phenomenon of underreporting and should also try to maintain the same sampling effort of spatial reporting., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Wildlife mortality caused by vehicles is a serious conservation and economic problem as collisions with large mammals are global, pervasive and increasing. We analysed 14,989 reports of ungulate-vehicle collisions (UVC) that occurred in Lithuania from 2002 to 2017. We analysed UVC data for four major ungulate species (roe deer, red deer, moose and wild boar) and checked for potential seasonal or daily trends. The temporal distribution of collisions was species-dependent. UVC analysis showed strong monthly and hourly pattern. Most occurrences took place before or during sunrise (dawn) and after or during sunset (dusk) during the year. In spring, the highest UVC peaks occurred early in the morning and late in the evening, while in winter these peaks occurred in late mornings and early evenings. With most UVC occurring on Fridays, daily variations were weak. We conclude that temporal variations of UVC distributions are result of a complex interaction of phenological factors and animal behaviour. The information provided in this study reinforces the knowledge on the dynamics and patterns of UVC and represents an important element for the identification of mitigation measures. Our findings suggest that efforts to reduce UVC should also focus on driver attitudes considering the seasonal and daily variations in UVC., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The fragmentation of forests by agricultural expansion, urbanization, and road networks is an ongoing global biodiversity crisis. In Southeast Asia and other tropical regions, wildlife populations are being isolated into pockets of natural habitat surrounded by road networks and monoculture plantations. Mortality from wildlife-vehicle collisions (WVCs) is contributing to a decline in many species of conservation priority in human-modified landscapes. This study is the first in Malaysia to investigate factors affecting the occurrence of WVCs. We assessed roadkill data gathered by the Department of Wildlife and National Parks on small-, medium-, and large-sized mammals in Peninsular Malaysia. We examined the relationship between wildlife road accidents and several environmental factors. We found a total of 605 roadkill animals, involving 21 species, which included three species classified as Endangered. Road type (plantation road or highway), year, and distance of the road from continuous and fragmented forests were significant in determining mammal mortality. Unexpectedly, the majority of road mortality occurred on palm oil plantation roads compared to highways. Mortality of small- and medium-sized mammals was greater at locations further from continuous forest than those closer to fragmented forests. Segmentation of continuous forest by roads should be avoided wherever possible to reduce the threat of roads on crossing wildlife., Competing Interests: The authors declare that they have no conflict of interest., (© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

One of the most evident and direct effects of roads on wildlife is the death of animals by vehicle collision. Understanding the spatial patterns behind roadkill helps to plan mitigation measures to reduce the impacts of roads on animal populations. However, although roadkill patterns have been extensively studied in temperate zones, the potential impacts of roads on wildlife in the Neotropics have received less attention and are particularly poorly understood in the Western Amazon. Here, we present the results of a study on roadkill in the Amazon region of Ecuador; a region that is affected by a rapidly increasing development of road infrastructure. Over the course of 50 days, in the wet season between September and November 2017, we searched for road-killed vertebrates on 15.9 km of roads near the city of Tena, Napo province, for a total of 1,590 surveyed kilometers. We recorded 593 dead specimens, predominantly reptiles (237 specimens, 40%) and amphibians (190, 32%), with birds (102, 17%) and mammals (64, 11%) being less common. Recorded species were assigned to three functional groups, based on their movement behavior and habitat use ("slow," "intermediate," and "fast"). Using Ripley's K statistical analyses and 2D HotSpot Identification Analysis, we found multiple distinct spatial clusters or hotspots, where roadkill was particularly frequent. Factors that potentially determined these clusters, and the prevalence of roadkill along road segments in general, differed between functional groups, but often included land cover variables such as native forest and waterbodies, and road characteristics such as speed limit (i.e., positive effect on roadkill frequency). Our study, which provides a first summary of species that are commonly found as roadkill in this part of the Amazon region, contributes to a better understanding of the negative impacts of roads on wildlife and is an important first step toward conservation efforts to mitigate these impacts., Competing Interests: None declared., (© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Road vehicle collisions are likely to be an important contributory factor in the decline of the European hedgehog ( Erinaceus europaeus) in Britain. Here, a collaborative roadkill dataset collected from multiple projects across Britain was used to assess when, where and why hedgehog roadkill are more likely to occur. Seasonal trends were assessed using a Generalized Additive Model. There were few casualties in winter-the hibernation season for hedgehogs-with a gradual increase from February that reached a peak in July before declining thereafter. A sequential multi-level Habitat Suitability Modelling (HSM) framework was then used to identify areas showing a high probability of hedgehog roadkill occurrence throughout the entire British road network (∼400,000 km) based on multi-scale environmental determinants. The HSM predicted that grassland and urban habitat coverage were important in predicting the probability of roadkill at a national scale. Probabilities peaked at approximately 50% urban cover at a one km scale and increased linearly with grassland cover (improved and rough grassland). Areas predicted to experience high probabilities of hedgehog roadkill occurrence were therefore in urban and suburban environments, that is, where a mix of urban and grassland habitats occur. These areas covered 9% of the total British road network. In combination with information on the frequency with which particular locations have hedgehog road casualties, the framework can help to identify priority areas for mitigation measures., Competing Interests: Patrick Graham Ross Wright is employed by the Mammal Society. Frazer Guy Coomber and Prof Fiona Mathews are both honorary members of the Mammal Society. Chloe Bellamy is employed by Forest Research., (© 2019 Wright et al.)

We modelled the spatiotemporal patterns of road mortality for seven medium-large mammals, using a roadkill dataset from Mato Grosso do Sul, Brazil (800 km of roads surveyed every two weeks, for two years). We related roadkill presence-absence along the road sections (1000 m) and across the survey dates with a collection of environmental variables, including land cover, forest cover, distance to rivers, temperature, precipitation and vegetation productivity. We further included two variables aiming to reflect the intrinsic spatial and temporal roadkill risk. Environmental variables were obtained through remote sensing and weather stations, allowing the estimate of the roadkill risk for the entire surveyed roads and survey periods. Overall, the models could explain a small fraction of the spatiotemporal patterns of roadkills (<0.23), probably due to species being habitat generalists, but still had reasonable discrimination power (AUC averaging 0.70 ± 0.07). The intrinsic spatial and temporal roadkill risk were the most important variables, followed by land cover, climate and NDVI. We show that identifying spatiotemporal roadkill patterns may provide valuable information to define specific management actions focused on road sections and time periods, in complement to permanent road mitigation measures. Our approach thus offers a new insight into the understanding of road effects and how to plan and strategize monitoring and mitigation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Adjustment for spatial and temporal trends using a Generalised Additive Model with Poisson error also failed to detect a significant VF effect. A simulation study used to estimate the power to detect a statistically significant reduction in roadkill rate gave, for median estimates of reduction of 21%, 48%, and 57%, estimates of power of 0.24, 0.78, and 0.91, respectively. Therefore, this study failed to confirm previously reported estimates of reduction in roadkill rates claimed for this VF of 50%-90%, despite having adequate power to do so. However, point estimates obtained for these three species of reductions ranging from 13% to 32% leave open the question of there being a real but modest effect that was below statistical detection limits., Competing Interests: The authors declare no conflict of interest.

Schemes to reduce road impacts on amphibians have been implemented for decades in Europe, yet, several aspects on the effectiveness of such schemes remain poorly understood. Particularly in northern Europe, including Sweden, there is a lack of available information on road mitigation for amphibians, which is hampering implementation progress and cost-effectiveness analyses of mitigation options. Here, we present data derived from systematic counts of amphibians during spring migration at three previous hot-spots for amphibian roadkill in Sweden, where amphibian tunnels with guiding fences have been installed. We used the data in combination with a risk model to estimate the number of roadkills and successful crossings before vs. after mitigation and mitigated vs. adjacent non-mitigated road sections. In mitigated road sections, the estimated number of amphibians killed or at risk of being killed by car traffic decreased by 85-100% and the estimated number successfully crossing the road increased by 25-340%. Data, however, suggested fence-end effects that may moderate the reduction in roadkill. We discuss possible explanations for the observed differences between sites and construction types, and implications for amphibian conservation. We show how effectiveness estimates can be used for prioritizing amphibian passages along the existing road network. Finally, we emphasize the importance of careful monitoring of amphibian roadkill and successful crossings before and after amphibian passages are constructed., Competing Interests: Silviu O. Petrovan is non-paid trustee (board of directors) of Froglife, a charity (non-profit) NGO.

In contrast to other fields, environmental protection (e.g., habitat protection) often fails to include quantitative evaluation as part of the existing environmental impact assessment (EIA) process, and therefore the EIA is often a poor forecasting tool, which makes selecting a reasonable plan of action difficult. In this study, we used the Habitat Evaluation Procedure (HEP) to quantify the long-term effects of a road construction project on an ecosystem. The water deer ( Hydropotes inermis ) was selected as the species of study since it uses an optimum habitat; water deer habitat data were collected on vegetation cover, stream water density, geographic contour, land use class, and road networks. The Habitat Suitability Index (HSI) and Cumulative Habitat Unit (CHU) values for the water deer were estimated to investigate the major land cover classes, the national river systems, and vegetation cover. Results showed that the environmental impact in the road construction project area would result in a net ecological loss value of 1211 without installation of an eco-corridor, which reduced to 662 with an eco-corridor, providing a 55% increase in the net value after 50 years of the mitigation plan. Comparing the 13 proposed ecological mitigation corridors, the corridor that would result in the highest net increase (with an increase of 69.5), was corridor #4, which was regarded as the most appropriate corridor to properly connect water deer habitat. In sum, the study derived the net increase in quantitative values corresponding with different mitigation methods over time for a road construction project; this procedure can be effectively utilized in the future to select the location of ecological corridors while considering the costs of constructing them.

Small- and medium-sized mammals play an important role in the life cycle of tick-borne pathogens in urban habitats. Our aim was to apply the general protocol, DAMA (documentation-assessment-monitoring-action), which is an integrated proposal to build a proactive capacity to understand, anticipate, and respond to the outcomes of accelerating environmental change. Here we tested whether road-killed carcasses in urban areas are useful sources of tissue and parasite samples to investigate these species' contribution to the epidemiology of vector-borne diseases. We collected 29 road-killed and 6 carcasses with different causes of mortality (23 northern white-breasted hedgehogs and 12 from seven other mammal species) mainly from Budapest, Hungary. We used quantitative and conventional PCRs to determine pathogens in 90 collected tissues (52 from hedgehogs; 38 from other species) and 417 ticks that were only found on hedgehogs. Tissue samples revealed a wide range of bacteria including human zoonotic pathogens identified as Anaplasma phagocytophilum ecotype I, Borrelia afzelii, B. spielmanii, Borrelia miyamotoi, Rickettsia helvetica, and Bartonella species. Among the 23 collected hedgehog carcasses, 17 (74%) were infected with A. phagocytophilum, 6 (26%) with Borrelia burgdorferi s.l., 12 (52%) with R. helvetica, and 15 (65%) with Rickettsia sp. Furthermore, we report the first detection of Rickettsia sp. infection in European moles and lesser weasel and R. helvetica in stone marten. Through sequencing B. afzelii, R. helvetica, R. monacensis and A. phagocytophilum ecotype I were identified in the ticks removed from the carcasses. We showed that road-killed urban mammal species are exposed to multiple tick-borne pathogens but further studies have to clarify whether they, in fact, also have a role in their maintenance and spread. Our study also demonstrates that roadkill can be used in the risk assessment of potential human infection and in the implementation of the DAMA protocol., (© 2018 Blackwell Verlag GmbH.)

Pheasants ( Phasianus colchicus ) are commonly killed on UK roads, presenting a threat to motorists and a loss to the game shooting industry. Pheasants may be inherently susceptible, or the recent increase in their artificial rearing and release may have exacerbated the situation, either through population increases or because artificial rearing has altered movement behaviour. We compared intra-annual patterns of roadkill reported in the UK from the 1960s (prior to the onset of mass release programmes) with that from the 2010s (when pheasant release was well established and widespread), considering roadkill sex and locations and accounting for changes in traffic levels. Pheasants in the UK are disproportionately likely to be reported killed on roads. However, this likelihood has not changed notably over the past 50 years. Instead, the timing of roadkill has changed. Pheasants in the 2010s are no longer susceptible during their breeding season, unlike in the 1960s, perhaps because relatively few breed successfully. Instead, roadkill first peaks in September-November as pheasants disperse from release pens, females first. Roadkill declines over winter, but when supplementary feeding ceases in February, we see a second peak in roadkill. Roadkill rates are higher in regions of the UK where there is little arable farming and hence natural food supplies are scarce., Competing Interests: We have no competing interests to declare.

Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application., Competing Interests: The authors declare they have no competing interests. All authors are employees of Data61, Commonwealth Scientific and Industrial Research Organisation.