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Wildlife‐vehicle collisions (WVCs) are a major source of wildlife mortality and should affect regional wildlife diversity and abundance, yet most WVC studies are locally scaled. Here, we evaluated biogeographic diversity (i.e., species richness, effective diversity) and abundance of WVCs at state parks across the Florida peninsula to answer two questions aimed to help inform wildlife conservation efforts: which parks have greatest WVC diversity, and why? We processed and compiled 9,254 WVC survey records collected by Florida State Parks personnel at 42 parks during a decade (2005–2015). Data for birds (138 species), mammals (35 species), reptiles (64 species), and all taxa combined were analyzed for patterns among parks (for the first question) and for biogeographic, climatic, ecoregion, and anthropogenic predictors of those patterns (for the second). Predictors represented nonexclusive alternative a priori hypotheses and were evaluated by model comparison. Parks differed widely in WVC diversity and abundance; we identify "hot spot" parks where management may most effectively reduce WVCs. Biogeographic and anthropogenic hypotheses were supported, but climatic and ecoregion hypotheses were not. Models for overall diversity fit data better (R2s > 0.50) than did models for specific taxa (e.g., birds). Larger parks closer to Florida's highly populated Atlantic Coast and with greater park attendance and perhaps faster speeds on adjacent roads have more WVC diversity and numbers. Of these predictors, attendance and speed limits are manageable. Traffic management in and near‐identified "hot spot" parks in Florida can most effectively reduce WVC effects on wildlife populations and diversity amidst a growing human population. [ABSTRACT FROM AUTHOR]

Road development, traffic intensification, and collisions with wildlife represent a danger both for road safety and species conservation. For planners, deciding which mitigation methods to apply is often problematic. Through a kernel density estimate, we analyzed 715 crossing locations and wildlife–vehicle collisions (WVCs) involving brown bears, lynx, wolf, red deer, roe deer, and wild boar in the Southeastern Carpathian Mountains. We identified 25 WVC hotspots, of which eight require urgent mitigation of existing infrastructure. Moreover, many of these hotspots are in Natura 2000 sites, along road sections where vegetation is in close proximity, animal movement is the highest, and driver visibility is low. Our study is the first in Romania to recommend practical solutions to remediate WVC hotspots and benefit sustainable landscape management. [ABSTRACT FROM AUTHOR]

The impact of wildlife--vehicle collisions on drivers and wildlife populations has been gaining attention in the United States. Given the established success of wildlife crossings with fencing in reducing wildlife crashes and connecting habitat, information is needed on cost-effective means of implementation for departments of transportation. When wildlife crossings are constructed, they are often built into new road projects as a series of 2 or more underpasses and/or overpass structures connected by exclusionary fencing. Given limited transportation budgets and the prevalence of maintenance activities more so than new construction in many states, enhancing existing underpasses on previously constructed roads has been recognized as a cost-effective mitigation opportunity. More research is needed, however, on the effects of adding fencing to existing underpasses, particularly those that are too far from one another to be connected with contiguous fencing. In this study, we evaluated the effectiveness of this measure when applied to isolated underpasses. Approximately 1.6 km of 2.4-m-high wildlife fencing was added to each of 2 existing underpasses, a large bridge underpass and a large box culvert, situated approximately 8 km apart from one another on Interstate 64 in Virginia, USA. We conducted a 2-year post-fencing camera monitoring study and compared the findings from a 2-year pre-fencing study with regard to collision frequencies with white-tailed deer (Odocoileus virginianus) and black bears (Ursus americanus); the use of the underpasses by wildlife; and roadside deer activity. We also evaluated deer activity data to compare different fence end designs applied at the study sites. After fencing installation, deer--vehicle collisions (DVCs) were reduced by 96.5% and 88% at the box culvert and bridge underpass, respectively, and there were no increases in DVCs within 1.6 km of the fence ends. Deer crossings increased 410% at the box culvert and 71% at the bridge underpass. Use of the culvert and bridge underpasses by other mammals increased 81% and 165%, respectively. Although deer use of the underpasses was much greater than their activity at any of the fence ends, there was relatively high deer activity at the fence ends that did not tie into a feature such as right-of-way fencing. Our study found that the addition of wildlife fencing to certain existing isolated underpasses can be a highly cost-effective means of increasing driver safety and enhancing habitat connectivity for wildlife. The benefits from crash reduction exceeded the fencing costs in 1.8 years, and fencing resulted in an average saving of >$2.3 million per site over the 25-year lifetime of the fencing. The results add to the growing body of knowledge about effective ways we can use existing infrastructure to connect wildlife habitat and increase driver safety. [ABSTRACT FROM AUTHOR]

Context: Road networks can negatively impact wildlife populations through habitat fragmentation, decreased landscape connectivity, and wildlife-vehicle collisions, thereby influencing the spatial ecology and population dynamics of imperiled species. The ocelot (Leopardus pardalis) is a federally endangered wild felid in South Texas, with a high mortality rate linked to vehicle collisions. Objectives: Using a multi-scale approach, we quantified and examined landscape spatial structure at ocelot roadkill locations, and between roadkill locations of male and female ocelots. Methods: We quantified the spatial distribution of land cover types at 26 ocelot–vehicle collision sites in South Texas that occurred from 1984–2017. We compared landscape metrics of woody, herbaceous, and bare ground cover types across multiple spatial scales at roadkill locations to those from random road locations, and between male and female ocelots. Results: Roadkill sites consisted of 13–20% more woody cover than random locations. Woody patches at roadkill sites were 7.1–11% larger (2.4 ha) closer to roads and spaced 10–16 m closer together farther away from roads compared to random locations. Percent woody cover was the best indicator of ocelot–vehicle collision sites; there were no differences in woody cover between male and female road mortality locations. Conclusion: These findings suggest that ocelots are likely struck by vehicles while crossing between habitat patches. Roads that bisect areas of woody cover have negative impacts on ocelots by increasing habitat fragmentation and vulnerability to vehicle collisions. Crossing structures should be placed in areas with ≥ 30% woody cover and 3.5 ha woody patches. [ABSTRACT FROM AUTHOR]

Systematic road-kill surveys are useful to study the impact of roads on wildlife. However, they are time-and budget-consuming, so the use of non-systematic data in road ecology is currently gaining popularity (for instance, by environmental consultants). Some data sources such as atlases (i.e., compilations of species records from a given region), which can include non-systematic and citizen-science data, can entail several intrinsic biases, mostly due to uneven sampling effort and uneven species detectability. Here, we tested this prediction by verifying if data from the Spanish Atlas of Terrestrial Mammals mirror the road-kill patterns obtained from our own systematic roadkill surveys. We focused on the Mediterranean mesocarnivore guild due to its easy identification by citizens involved in atlas-data collection. We tested if the relative abundance of each species, their richness and diversity obtained from Atlas and our systematic surveys were related, using linear models, while controlling for human population and road density (potentially confounding effects). We further compared the patterns of species abundance obtained from both sources. Our results highlight that road-kill patterns do not mirror the Atlas patterns for the three metrics evaluated. This is probably due to survey biases in typical data from wildlife atlases. When analysing species individually, we found that some species are road-killed more (or less) than expected in relation to their abundance in atlas records. These results are probably due to species-specific ecological or behavioural traits such as species morphology or species behaviour when facing the road. We suggest that abundance from atlas data should not be used as a proxy for road-kill rates. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the incidence of car accidents with cloven-hoofed game over a 5-year period in the Košice region. The highest number of accidents occurred on 1st class roads (11.18%), which are the shortest and most frequently occurring roads in Slovakia. There were a total of 4.1 animals/km found on such roads within the Košice region. Accidents occurred most frequently during April, October and November; with roe deer being the most commonly affected (62.12%). The roadkill numbers for red deer (21.59%) and wild boar (16.29%) were highest during October and November. These road traffic accidents were mostly related to the migration of game, especially during the rutting season. The time of the collision for each game species was also recorded. It was found that the majority of collisions involving roe deer occurred between 05.00–06.00 and 18.00–21.00, the collisions with red deer occurred most commonly between 21.00–22.00,and collisions involving wild boars occurred between 20–23.00. Over the 24-hour period studied (day, night, dusk and dawn), it was found that from the traffic collisions during the day, roe deer constituted the highest number of roadkill (28.35%). However, during the night, incidents involving wild boar were most frequent (84.88%). The number of car accidents involving cloven-hoofed game was the least frequent during dusk (6.25%), followed by dawn (11.37%) over the 24-hour period. [ABSTRACT FROM AUTHOR]

Ungulate–vehicle collisions pose a traffic safety issue as well as wildlife-conservation issues in many countries. While fences are recommended as reliable safety measures for motorways and other high-traffic volume roads, no generally accepted measures of the same efficiency are available for secondary roads. Odour repellents are applied in many central European countries, but contradictory results are available concerning their efficiency. We tested the effect of odour repellents on both a crossing frequency and the presence near roads of six individuals of roe deer over a period of five months (April–August 2019). The odour repellents were installed along two secondary roads, and along two semi-open habitats (forest–meadow and forest–arable land) alternately, in several phases. Two hypotheses were tested. The first one focused on the change in animal presence close to the profiles where the odours were applied, while the second hypothesis concerned a change in the number of crossings of the same profiles. The results demonstrate that no clear effect of odour repellents on roe deer behaviour in both hypotheses were obtained. Apart from the obtained results, we discuss the importance of the methodology. We conclude that this kind of study design is extremely sensitive to a number of factors with a potentially negative influence on the course of the study design. [ABSTRACT FROM AUTHOR]

Road networks are increasing globally, and as such incur increased pressure on wildlife communities. Large‐scale road expansion and infrastructure development occurring throughout Asia (i.e. Belt and Road Initiative) will affect hundreds of threatened species, leading to an increase in wildlife‐vehicle collisions. However, only a limited number of studies have quantified road mortality within this threatened landscape. To rectify this, we monitored the spatial‐temporal patterns of vertebrate roadkill in the Dong Phayayen‐Khao Yai forest complex, an UNESCO World Heritage Site located in Thailand, considered a refuge for many globally threatened species. We ran 100 standardized road surveys between 2015 and 2017, on a 47.8‐km highway transect currently being expanded, and recorded a total of 1395 casualties from 124 species. After correcting for removal time and detection probability, we estimated an average of 9688 vertebrate mortalities per year. We observed a mortality peak during the dry season for almost all taxonomic groups, due to a combination of high bird and bat mortality events. All taxa showed significant spatial clustering, highlighting high‐risk road sections. We modelled the road and landscape features most likely to lead to higher mortality rates, disentangling small‐scale (250–500 m from road) from large‐scale effects (1000–2500 m). We recorded lower mortality rates and species diversity near forest sites in protected areas, representing either lower crossing events due to habitat quality or an already depleted environment. Spatial analyses provided information on hotspots and landscape factors, which can be used to inform future mitigations at multiple scales throughout the Southeast Asia region. Our study provides a baseline of the direct road impacts on vertebrate species in a tropical biodiversity hotspot, and we suggest that more studies be conducted to fully assess the direct road effects on the many threatened species in this landscape. [ABSTRACT FROM AUTHOR]

Worldwide, the persistent trend of human and animal life losses, as well as damage to properties due to wildlife–vehicle collisions (WVCs) remains a significant source of concerns for a broad range of stakeholders. To mitigate their occurrences and impact, many approaches are being adopted, with varying successes. Because of their increased versatility and increasing efficiency, Artificial Intelligence-based methods have been experiencing a significant level of adoption. The present work extensively reviews the literature on intelligent systems incorporating sensor technologies and/or machine learning methods to mitigate WVCs. Included in our review is an investigation of key factors contributing to human–wildlife conflicts, as well as a discussion of dominant state-of-the-art datasets used in the mitigation of WVCs. Our study combines a systematic review with bibliometric analysis. We find that most animal detection systems (excluding autonomous vehicles) are relying neither on state-of-the-art datasets nor on recent breakthrough machine learning approaches. We, therefore, argue that the use of the latest datasets and machine learning techniques will minimize false detection and improve model performance. In addition, the present work covers a comprehensive list of associated challenges ranging from failure to detect hotspot areas to limitations in training datasets. Future research directions identified include the design and development of algorithms for real-time animal detection systems. The latter provides a rationale for the applicability of our proposed solutions, for which we designed a continuous product development lifecycle to determine their feasibility.

Wildlife-vehicle collisions imperil humans, wildlife, and property. Collisions with moose (Alces alces ) are especially consequential and there are indications they may increase during severe winters. We tested hypotheses regarding the influence of moose movements and vehicular traffic patterns on collision risk. We first modeled daily snow depth and accumulation across 5.6 million km ^2 of the North American Arctic-Boreal region. Next, we analyzed the movements and road use of 113 GPS-collared moose in response to snow depth. Finally, we examined the influence of these snow properties on vehicular traffic and 7680 moose-vehicle collisions. As winter progressed and the snowpack deepened in each study area, GPS-collared moose migrated to lower elevations, leading them into areas with shallower snow but higher road densities. This elevational migration corresponded with a higher probability of road-use by moose (by up to ten-fold) in winter than in summer. Corresponding to these patterns, moose-vehicle collisions were 2.4–5.7 times more frequent from December through February (compared to early summer). Collision risk was highest when and where snow depth was less than 120 cm, indicating that migration into areas with shallower snow increased collision risk in those areas. Most (82%) moose-vehicle collisions occurred after dark. This pattern was strongest during winter, when nighttime traffic volumes were eight times higher than summer due to longer nights. Overall, our findings suggest that concurrent seasonal changes in human and wildlife behavior increase the frequency of moose-vehicle collisions during winter. Snow depth influences collisions primarily through its impacts on moose movement, while strong seasonal changes in daylight hours cause an increase in nighttime traffic that further contributes to risk. This information may help predict times and places where risk of moose-vehicle collisions are highest and to develop seasonally dynamic mitigation strategies.

Vehicle collisions with animals pose serious issues in countries with well-developed highway networks. Both expanding wildlife populations and the development of urbanised areas reduce the potential contact distance between wildlife species and vehicles. Many recent studies have been conducted to better understand the factors that influence wildlife–vehicle collisions (WVCs) and provide mitigation methods. Most of these studies examined road density, traffic volume, seasonal fluctuations, etc. However, in analysing the distribution of WVC, few studies have considered a spatial and significant distance geostatistical analysis approach that includes how different land-use categories are associated with the distance to WVCs. Our study investigated the spatial distribution of agricultural land, meadows and pastures, forests, built-up areas, rivers, lakes, and ponds, to highlight the most dangerous sections of roadways where WVCs occur. We examined six potential ‘hot spot’ distances (5–10–25–50–100–200 m) to evaluate the role different landscape elements play in the occurrence of WVC. The near analysis tool showed that a distance of 10–25 m to different landscape elements provided the most sensitive results. Hot spots associated with agricultural land, forests, as well as meadows and pastures, peaked on roadways in close proximity (10 m), while hot spots associated with built-up areas, rivers, lakes, and ponds peaked on roadways farther (200 m) from these land-use types. We found that the order of habitat importance in WVC hot spots was agricultural land < forests < meadows and pastures < built-up areas < rivers < lakes and ponds. This methodological approach includes general hot-spot analysis as well as differentiated distance analysis which helps to better reveal the influence of landscape structure on WVCs.

Ungulate-proof fencing has been used successfully to mitigate the incidence of wildlife-vehicle collisions on highways throughout North America. And while fencing is often regarded as an integral component of effective wildlife passage structures, limited information or guidelines exist for the application of fencing in conjunction with wildlife passages. Fencing itself may limit wildlife permeability across highways and exacerbate the barrier effect of highways on wildlife populations. An 8-km section of highway reconstructed from a two- to four-lane divided highway in central Arizona was opened to traffic six months before ungulate-proof fencing was erected linking four wildlife underpasses (UP) and three bridges. To assess the role of strategically placed fencing along 49% of the section, we compared before and after fencing Rocky Mountain elk (Cervus elaphus nelsoni)-vehicle collision incidence, wildlife use of UP, and elk highway permeability. From 2002–2006, we documented 110 elk-vehicle collisions. The incidence of collisions increased over three fold after highway reconstruction was completed but before fencing was erected. After fencing, the incidence of elk collisions declined 87%. We employed video camera surveillance systems at two UP to compare wildlife use for nine months before and 11 months after fencing was erected. Before fencing, we recorded 500 elk and deer (Odocoileus spp.) at the UP, of which only 12% successfully passed through the UP; 81% of animals continued to cross the highway at grade. After fencing, of 595 elk and deer recorded, 56% crossed successfully and no animals crossed the highway at grade. The probability of an approaching animal crossing through an UP increased from 0.09 to 0.56 with fencing, and the combined odds of a crossing through the UP after fencing was 13.6:1 compared to before fencing. We used Global Positioning System (GPS) telemetry to assess highway permeability and crossing patterns. We instrumented 22 elk (16 female, 6 male) with GPS receiver collars April 2004–October 2005, during which time our collars accrued 87,745 GPS fixes. The elk highway passage rate, our measure of permeability, after the highway was opened to traffic but before fencing was erected (0.54 crossings/approach) was 32% lower than the level determined from a previous study for the section during reconstruction (0.79 crossings/approach). Once fencing was erected, the passage rate increased 52% to 0.82 crossings/approach. The proportion of elk crossings that occurred along fenced highway stretches declined 50% while the proportion of crossings along unfenced highway increased 40%. Fencing plays an important role in reducing the incidence of wildlife-vehicle collisions and increasing the effectiveness of wildlife passage structures. Furthermore, fencing in combination with a relatively high density of passages (1 struc¬ture/1.1 km) promoted elk highway permeability by funneling animals toward the UP where resistance to crossing was lower than that associated with crossings at grade.

Roads have been recognized as a threat to wildlife species for over 80 years. Studies on the effects of roads on ungulates species did not begin till the 1970’s. We identified 53 literature sources that suggested or examined traffic levels or road types and their effects on ungulate-vehicle collisions, ungulate distribution and roadway perme¬ability. Seventy-one percent of these suggested an effect of traffic level on ungulates. Only 47% of the papers suggested deer (Odocoileus spp.) were affected by traffic while in contrast studies on elk (Cervus elaphus) and moose (Alces alces) were at 84% and 82%, respectively. In studies that suggested no effect of traffic, other factors such as ungulate populations, ungulate behavior, driver behavior, and landscape variables were generally considered reasons for fluctuations in collisions. Although several studies examined ungulate distribution along roads, very few adequately looked at fluctuating traffic levels along highways. Highways have a greater potential for ungulate-vehicle collisions and are more likely to provide a barrier to ungulates than low traffic roads. Our further understanding of ungulate move¬ments and behavior in relationship to highways may be important in helping to mitigate ungulate-vehicle collisions and ungulate habitat fragmentation. Our State Route 260 project in central Arizona has provided a unique opportunity to examine elk movements in relation to traffic along a highway. We documented distinct shifts in distribution associated with fluctuating traffic levels as well as reductions in probabilities of at-grade crossings during increasing traffic levels. During the same study we found that increased traffic levels did not alter elk use of wildlife underpasses. Overall, properly designed wildlife underpasses and adequate funnel fencing adequately reduced elk-vehicle collisions while si¬multaneously promoting highway permeability during increasing traffic levels. Further research is needed to determine if these trends hold true for other ungulate species. Currently, research of fluctuating hourly traffic levels on ungulate behavior associated with highways is underway in Arizona, including American pronghorn (Antilocapra americana), mule deer (O. hemionus), Coues’ white-tailed deer (O. virginianus couseii) and further research on elk along highways with different geographical areas and traffic level ranges.

ABSTRACT Collisions between wildlife and vehicles are detrimental to both wildlife and human safety. A variety of mitigation methods have been deployed with the intent of increasing ungulate awareness of approaching vehicles. Wildlife warning reflectors are one such method. Roadside reflectors are designed to reflect headlights into the right‐of‐way and alert ungulates to approaching vehicles. Studies of the effectiveness of these reflectors have yielded mixed results. We conducted a robust test of reflectors in central Wyoming, USA, during 2013 and 2014, and unexpectedly discovered a potentially more effective method than the reflectors for reducing collisions between vehicles and mule deer (Odocoileus hemionus). In our initial experiment, we manipulated 10 1.6‐km segments of highway by leaving their reflectors exposed or covering them with a white canvas bag with the intention of neutralizing the reflector. The treatment configuration was swapped monthly. We counted deer carcasses under each treatment for 1 year and observed deer road‐crossing behavior using thermal video cameras. Carcass rates were 33% less in the white canvas treatment relative to uncovered reflectors. Deer in the white canvas treatment also stopped before entering the road 20% more often, ran into the road from the right‐of‐way 11% less often, and fled from the road 12% more often than when reflectors were uncovered. In a follow‐up experiment, we found that deer carcass rates were 32% less when reflectors were exposed versus covered with black canvas. We further found that deer road‐crossing behavior was least risky in a white canvas treatment, intermediate in a reflectors treatment, and most risky when reflectors were removed from posts. Taken together, these results indicate that, although reflectors were moderately effective, white canvas was substantially more effective in reducing deer–vehicle collisions. This unexpected finding suggests that new vigilance‐enhancing mitigation methods should be explored as a way to reduce wildlife–vehicle collisions. © 2018 The Wildlife Society.

The construction and continued use of transportation infrastructure, specifically roads, has had a significant global impact on biodiversity and the environment. The Republic of Korea, or South Korea, has a road density of 1.13 km/km2. So far, three nationwide studies about vertebrate road-killed species have been reported, showing bias towards medium to large mammals, the most common victims being the Korean water deer (Hydropotes inermis), Korean hare (Lepus coreanus), Siberian roe deer (Capreolus pygargus), and the common raccoon dog (Nyctereutes procyonoides). Road-kills, or wildlife-vehicle collisions (WVCs), tend to occur in or near preferred habitat types or in highly fragmented areas, with roads additionally being linked to habitat fragmentation and loss. Alongside WVCs and habitat effects, information about other adverse effects on biodiversity is scant, although there are reports that heavy metals and other pollutants from road runoff impact marine biodiversity, vegetation, soil, and groundwater. Furthermore, roads have been linked to a prevalence of invasive plant species. To mitigate road impacts, the South Korean government has constructed, with mixed results, 530 wildlife crossing structures, mainly including overpasses and tunnels. To mitigate road impacts more effectively, the country will need more construction, monitoring, and consistent management of wildlife crossing structures. Further, incorporating plans for wildlife crossing structures in early stages of road development will be required.

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.

I reviewed published and unpublished papers, government reports, and websites to estimate how many people are injured or killed each year by wildlife or stricken by a zoonotic disease. Over 47,000 people annually in the United States sought medical attention after being attacked or bitten by wildlife, and approximately 8 people died annually. Most bites were by snakes, birds, rodents, and raccoons (Procyon lotor). Each year, wildlife–vehicle collisions resulted in >59,000 human injuries and >440 human fatalities, while wildlife–aircraft collisions added 16 more injuries and 10 fatalities. I also found that >68,000 people each year sought medical assistance for a zoonotic disease, and 243 of these cases were fatal. When wildlife-related casualties and fatalities are summed, >174,000 people were injured or sickened and >700 were killed by wildlife annually. These figures do not mean that wildlife populations should be reduced; they do indicate, however, that wildlife biologists have an opportunity to serve society by preventing human injuries, morbidities, and fatalities resulting from wildlife. In doing so, wildlife biologists will also be protecting the future of wildlife.

Road development, traffic intensification, and collisions with wildlife represent a danger both for road safety and species conservation. For planners, deciding which mitigation methods to apply is often problematic. Through a kernel density estimate, we analyzed 715 crossing locations and wildlife–vehicle collisions (WVCs) involving brown bears, lynx, wolf, red deer, roe deer, and wild boar in the Southeastern Carpathian Mountains. We identified 25 WVC hotspots, of which eight require urgent mitigation of existing infrastructure. Moreover, many of these hotspots are in Natura 2000 sites, along road sections where vegetation is in close proximity, animal movement is the highest, and driver visibility is low. Our study is the first in Romania to recommend practical solutions to remediate WVC hotspots and benefit sustainable landscape management.

Context: Examining land cover's influences on roadkills at single predetermined scales is more common than evaluating multiple scales, but examining land cover at the appropriate scale may be necessary for efficient design of mitigation measures, and that appropriate scale may be difficult to discern a priori. In addition, the taxonomic rank at which data is analysed may influence results and subsequent conclusions concerning mitigation. Aims: The objective of the present study was to assess the influence of variation in spatial scales of land cover explanatory variables and taxonomic rank of response variables in models of wildlife–vehicle collisions (WVCs). Research questions include: (1) do the scales of land cover measurement that produce the highest quality models differ among species; (2) do the factors that influence roadkill events differ within species at different scales of measurement and among species overall; and (3) does the taxonomic rank at which data is analysed influence the selection of explanatory variables? Methods: Four frequent WVC species representing diverse taxonomic classes, i.e. two mammals (Cerdocyon thous and Hydrochaeris hydrochaeris), one reptile (Caiman yacare) and one bird (Caracara plancus), were examined. WVCs were buffered, land cover classes from classified satellite imagery at three buffer radii were extracted, and logistic regression model selection was used. Key results: The scale of land cover variables selected for the highest quality models (and the selected variables themselves) may vary among wild fauna. The same explanatory variables and formulae are not always included in the candidate models in all compared scales for a given species. Explanatory variables may differ among taxonomically similar species, e.g. mammals, and pooling species at higher taxonomic ranks can result in models that do not correspond with species-level models of all pooled species. Conclusions: The most accurate analyses of WVCs will likely be found when species are analysed individually and multiple scales of predictor variable collection are evaluated. Implications: Mitigating the effects of roadways on wildlife population declines for both common and rare species is resource intensive. Resources spent optimising models for spatially targeting management actions may reduce the amount of resources used and increase the effectiveness of these actions. Our aim was to examine how scale and taxonomic rank of analysis of wildlife–vehicle collisions (WVCs) may influence model selection and interpretations. We found that species may not agree on scale of analysis and explanatory variables in the highest quality models, and analysis of pooled species may not include explanatory variables that are significant at the individual species level. Accurate analyses of WVCs occur when species are analysed individually and multiple scales of land over variable collection are evaluated. Photograph by Julio Cesar de Souza. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop a new model for the prediction of wildlife-vehicle collisions (WVC) in urban areas, more specifically in the city of Lublin (Poland) and its surroundings. Prediction new model probability of WVC will be a valuable tool for city planners and will increase road safety for drivers and animals. The number of WVC was compared with data on traffic intensity in the same period, land use forms and seasons of the year. The data were analyzed statistically and the values of the parameters were presented as the mean value and standard error or standard deviation. Almost half (42.7%) of the analyzed collisions took place on roads characterized by traffic that does not exceed 100 vehicles/day. The highest number of collisions with animals was reported in summer and spring, i.e. 91 and 78 events, respectively. There was also a highly significant positive correlation between the increase in the number of accidents with animals and the traffic intensity of 501-600 and 1101-1200 vehicles/day on the roads. The distances from river valleys, residential buildings, and industrial development turned out to be significant predictor variables for WVC. [ABSTRACT FROM AUTHOR]

Roadkill is among the most severe and insidious causes of impoverishment of vertebrate populations. As large roadkill databases develop, inferences from roadkill data can inform landscape-scale studies with broad conservation aims. The Taiwan Roadkill Observation Network (TaiRON) is one of the largest roadkill databases, and we elucidated taxonomic, seasonal, and temporal trends of roadkill in Taiwan, as well as patterns of protected species roadkill. Notably, the study revealed that snakes were the largest proportion of all roadkill (35%) and 26% of snake roadkills were of protected species. Additionally, the top 23 species of a total 496 species ranked by roadkill abundance made up 50% of the observations. During winter, there were significantly fewer roadkill observations of bats, lizards, and snakes, but birds and mammals had fairly consistent roadkill across seasons. Additionally, 19% percent of the observations were of protected species. The staggering magnitude and extent of roadkill observations collected by TaiRON indicates a clear impact of roads of on Taiwan's vertebrate fauna. The patterns demonstrate that certain taxonomic groups are disproportionately killed on roads, and a small number of species account for most of the mortality. Additionally, certain seasons account for higher frequency of road kills, especially for ectothermic taxa. These are important insights, as this means that there are groups that are highly and disproportionately affected by roads. We hope this first synthesis of all data from TaiRON provides an understanding of the magnitude of roadkill in Taiwan to inform conservation action. [ABSTRACT FROM AUTHOR]

I reviewed published and unpublished papers, government reports, and websites to estimate how many people are injured or killed each year by wildlife or stricken by a zoonotic disease. Over 47,000 people annually in the United States sought medical attention after being attacked or bitten by wildlife, and approximately 8 people died annually. Most bites were by snakes, birds, rodents, and raccoons (Procyon lotor). Each year, wildlife-vehicle collisions resulted in >59,000 human injuries and >440 human fatalities, while wildlife-aircraft collisions added 16 more injuries and 10 fatalities. I also found that >68,000 people each year sought medical assistance for a zoonotic disease, and 243 of these cases were fatal. When wildliferelated casualties and fatalities are summed, >174,000 people were injured or sickened and >700 were killed by wildlife annually. These figures do not mean that wildlife populations should be reduced; they do indicate, however, that wildlife biologists have an opportunity to serve society by preventing human injuries, morbidities, and fatalities resulting from wildlife. In doing so, wildlife biologists will also be protecting the future of wildlife. [ABSTRACT FROM AUTHOR]

The growing wildland‐urban interface is a frontier of human‐wildlife conflict worldwide. Where natural and developed areas meet, there is potential for negative interactions between humans and wild animals, including wildlife‐vehicle collisions. Understanding the environmental and anthropogenic factors leading to these collisions can inform transportation and habitat planning, with an objective of reducing animal mortality and human costs. We investigated spatial, temporal, and species‐specific patterns of roadkill on Interstate‐280 (I‐280) in California, USA, and examined the effects of land cover, fencing, lighting, and traffic. The highway is situated just south of San Francisco, dividing a large wildlife refuge to the west from dense residential areas to the east, and therefore presents a major barrier to wildlife movement. Areas with a higher percentage of developed land east of I‐280 and areas with more open space on the west side of I‐280 were associated with an increase in overall roadkill, suggesting that hard boundaries at the wildland‐urban interface may be zones of high risk for dispersing animals. This pattern was especially strong for raccoons (Procyon lotor) and black‐tailed deer (Odocoileus hemionus). The presence of lighting correlated with increased roadkill with the exception of coyote (Canis latrans). Contrary to our expectations, we found weak evidence that fencing increases roadkill, perhaps because animals become trapped on roadways or because fencing is not sufficient to block access to the road by wildlife. Finally, we found strong evidence for roadkill seasonality, correlated with differences in movement and dispersal across life‐history stages. We highlight the value of citizen‐science datasets for monitoring human‐wildlife conflict and suggest potential mitigation measures to reduce the negative effects of wildlife‐vehicle collisions for people and wildlife. © 2019 The Wildlife Society. Using citizen science data on roadkill distribution, we evaluated spatial and seasonal patterns of wildlife‐vehicle collisions on a major highway that separates undeveloped wildlands from dense urban infrastructure in the San Francisco Bay Area, California, USA. We documented spatial hotspots and seasonal peaks in roadkill, likely associated with wildlife dispersal patterns at the wildland‐urban interface. [ABSTRACT FROM AUTHOR]

Abstract Wildlife-vehicle collisions (WVCs) pose a serious global issue. Factors influencing the occurrence of WVC along roads can be divided in general into two groups: spatially random and non-random. The latter group consists of local factors which act at specific places, whereas the former group consists of globally acting factors. We analyzed 27,142 WVC records (roe deer and wild boar), which took place between 2012 and 2016 on Czech roads. Statistically significant clusters of WVCs occurrence were identified using the clustering (KDE+) approach. Local factors were consequently measured for the 75 most important clusters as cases and the same number of single WVCs outside clusters as controls, and identified by the use of odds ratio, Bayesian inference and logistic regression. Subsequently, a simulation study randomly distributing WVC in clusters into case and control groups was performed to highlight the importance of the clustering approach. All statistically significant clusters with roe deer (wild boar) contained 34% (27%) of all records related to this species. The overall length of the respective clusters covered 0.982% (0.177%) of the analyzed road network. The results suggest that the most pronounced signal identifying the statistically significant local factors is achieved when WVCs were divided according to their occurrence in clusters and outside clusters. We conclude that application of a clustering approach should precede regression modeling in order to reliably identify the local factors influencing spatially non-random occurrence of WVCs along the transportation infrastructure. Highlights • Factors influencing WVCs can be divided in into two groups: spatially random and non-random. • Local (spatially non-random) factors were measured for the 75 clusters and 75 controls. • WVCs divided according to cluster occurrence returned the best signal for local factors. • Coldspots should not be used as controls and single WVCs as cases. • Application of the KDE+ approach to WVC data should precede regression modeling. [ABSTRACT FROM AUTHOR]

Abstract Road mortality is the most easily visible effect of roads and traffic on wildlife populations. Mitigation measures such as fences and wildlife passages have been applied to reduce these effects. During the widening of Quebec's Highway 175 from two to four lanes between 2006 and 2012, 33 wildlife passages designed specifically for small and medium-sized mammals were installed under the road in combination with short fences. This study examined the effectiveness of the fences at reducing the number of small and medium-sized mammals killed along a 68 km section of the road while controlling for the potential confounding effects of landscape variables. Repeated daily mortality surveys were conducted by car during the summers of 2012–2015 to measure roadkill occurrence and detection probability. A total of 893 dead animals from 13 taxa were detected. Roadkill occurrence was significantly greater at fence ends than in fenced sections and unfenced sections (fence-end effect), indicating that the fences were not long enough to discourage animals from moving along the fence to the fence ends. Greater length would be required to meet the target of reduced road mortality. Shrubby vegetation in the median strip separating the two directions of the highway was associated with high roadkill occurrence for medium-sized species. Roadkill detection probability for all species combined was 0.72, ranging from 0.17 for small mammals (<1 kg) to 0.82 for medium-sized mammals (>1 kg). To reduce road mortality, when wildlife passages are constructed along with new highways or retrofitted to old highways, fences either should be continuous or sufficiently long to encourage passage use rather than movement around the fence ends. Future road mortality studies should be combined with data about wildlife abundance and detection probability to more accurately estimate the effects at the population level. Graphical abstract Image Highlights • The study addresses the effectiveness of mitigation measures at reducing roadkill. • Detection probability ranged from 0.17 (small) to 0.82 (medium-sized mammals). • Landscape variables (distance to forest, etc.) influenced spatial roadkill patterns. • Roadkill levels were higher at fence ends than within fenced and unfenced sections. • The fences were not long enough to meet the target of road mortality reduction. [ABSTRACT FROM AUTHOR]

After reconstruction of a highway section with three wildlife underpasses, but only limited wildlife exclusion fencing, elk (Cervus canadensis)-vehicle collisions (EVC) increased 21%. We retrofitted an existing 1-m right-of-way fence along 4.2 km, raising it to 2.2−2.4 m in height and tying it into underpasses at the project's east end. With no logical western fence terminus, we installed an animal-activated detection system (AADS) and motorist alert signage at a designated at-grade crosswalk to prevent collisions when animals crossed. Our goal was to achieve modified motorist behavior without long-term habituation while allowing wildlife to cross via the crosswalk, promoting highway safety and landscape connectivity. Before-project EVC (9.33/year) declined 97% after the new fencing. Our AADS achieved reduced vehicle speeds (13%) and increased motorist alertness (5.5-fold increase) with signs activated. Average speed reduction and braking response remained significantly higher with sign activation across all 9 years of our evaluation. Thus, our place- and time-specific AADS design successfully modified motorist behavior without habituation. [ABSTRACT FROM AUTHOR]

Highway programmes typically focus on reducing vehicle collisions with large mammals because of economic or safety reasons, while overlooking the millions of birds that die annually from traffic. We studied wildlife–vehicle collisions along an interstate highway in southern Idaho, USA, with among the highest reported rates of American Barn Owl Tyto furcata road mortality. Carcass data from systematic and ad hoc surveys conducted in 2004–2006 and 2013–2015 were used to explore the extent to which spatial, road geometric and biotic factors explained Barn Owl–vehicle collisions. Barn Owls outnumbered all other identified vertebrate species of roadkill and represented > 25% of individuals and 73.6% of road‐killed birds. At a 1‐km highway segment scale, the number of dead Barn Owls decreased with increasing numbers of human structures, cumulative length of secondary roads near the highway and width of the highway median. The number of dead Barn Owls increased with higher commercial average annual daily traffic (CAADT), small mammal abundance index and grass rather than shrubs in the roadside verge. The small mammal abundance index was also greater in roadsides with grass vs. mixed shrubs, suggesting that Barn Owls may be attracted to grassy portions of the highway with more abundant small mammals for hunting prey. When assessed at a 3‐km highway segment scale, the number of dead Barn Owls again increased, with higher CAADT as well as with greater numbers of dairy farms. At a 5‐km scale, the number of dead Barn Owls increased with a greater percentage of cropland near the highway. Although human conversion of the environment from natural shrub‐steppe to irrigated agriculture in this region of Idaho has probably enhanced habitat for Barns Owls, it simultaneously has increased risk for owl–vehicle collisions where an interstate highway traverses the altered landscape. We review some approaches for highway mitigation and suggest that reducing wildlife–vehicle collisions involving Barn Owls may contribute to the persistence of this species. [ABSTRACT FROM AUTHOR]

This study examined whether the rising trends of wild boar (Sus scrofa)-vehicle accidents in Sweden are accompanied by a higher amount of personal injuries and costs. Temporal trends in accident frequencies and the number of persons injured in wild boar-vehicle accidents were examined for 2003-2016, and the cost of wild boar-vehicle accidents was calculated. Results show increases in the number of personal injuries, and increased costs, particularly after 2010-2012. The total number of wild boar accidents correlated with the number of injured persons as well as with the number of accidents with personal injuries. Approximately one person (1.13%) is injured per 100 wild boar-vehicle accidents, and approximately one accident per 200 wild boar-vehicle accidents will result in one or more persons with injuries (0.5%). However, most of the persons injured have slighter injuries. Although the number of wild boar-vehicle accidents and the number of persons injured in the accidents have increased, the frequency of accidents resulting in personal injuries is still at low levels in comparison with, for example, frequencies of personal injuries for moose accidents. The cost for wild boar-vehicle accidents has increased between 2003 to 2016 and is currently estimated to vary between approximately EUR 9.66-12.31 million per year. [ABSTRACT FROM AUTHOR]

We monitored reptile and bird roadkills in Cerrado-Pantanal landscapes along the Campo Grande to Corumbá highway BR-262. We describe species distribution in different landscape zones, including the first geographic record for Hydrodynastes bicinctus Herrmann, 1804 in the Pantanal basin. The roadkill occurrence of Spizaetus melanoleucus (Vieillot, 1816) is an outstanding record. We recorded 930 individuals belonging to 29 reptile and 47 bird species; 20 of these species are new roadkill records in Brazil. The 8 new records of reptile species include Eunectes notaeus Cope, 1862, Bothrops mattogrossensis Amaral,1925, Dracaena paraguayensis Amaral,1950 and H. bicinctus; and 12 new records of bird species include S. melanoleucus, Heterospizias meridionalis Latham, 1790, Urubitinga urubitinga (Gmelin, 1788), Pulsatrix perspicillata (Latham, 1790), Aramus guarauna (Linnaeus, 1766), and Jabiru mycteria (Lichtenstein, 1819). Richness of road-killed species on the BR-262 highway seemed to be high, reinforcing concerns about wildlife-vehicle collisions where these accidents occur, as they lead to long term and chronic impacts on wildlife and road safety in the Pantanal region. [ABSTRACT FROM AUTHOR]

Wildlife-vehicle collisions are a human safety issue and may negatively impact wildlife populations. Most wildlife-vehicle collision studies predict high-risk road segments using only collision data. However, these data lack biologically relevant information such as wildlife population densities and successful road-crossing locations. We overcome this shortcoming with a new method that combines successful road crossings with vehicle collision data, to identify road segments that have both high biological relevance and high risk. We used moose (Alces americanus) road-crossing locations from 20 moose collared with Global Positioning Systems as well as moose-vehicle collision (MVC) data in the state of Massachusetts, USA, to create multi-scale resource selection functions. We predicted the probability of moose road crossings and MVCs across the road network and combined these surfaces to identify road segments that met the dual criteria of having high biological relevance and high risk for MVCs. These road segments occurred mostly on larger roadways in natural areas and were surrounded by forests, wetlands, and a heterogenous mix of land cover types. We found MVCs resulted in the mortality of 3% of the moose population in Massachusetts annually. Although there have been only three human fatalities related to MVCs in Massachusetts since 2003, the human fatality rate was one of the highest reported in the literature. The rate of MVCs relative to the size of the moose population and the risk to human safety suggest a need for road mitigation measures, such as fencing, animal detection systems, and large mammal-crossing structures on roadways in Massachusetts. [ABSTRACT FROM AUTHOR]

Wildlife-vehicle collisions (WVC) pose a serious socio-economic and traffic safety issue. We investigated factors affecting the location and number of WVC on the expressway "Tri-City Bypass" in a suburban area in N Poland. We analysed WVC with large-sized (LSM; ungulates; 54% of roadkills) and small-sized mammals (SSM; mainly carnivores; 46% of roadkills) and both groups combined (AM). We identified WVC hotspots and analysed factors affecting their spatial distribution with Poisson regression based on four sets of landscape and road-related features (area, patchiness, presence and other features). The most frequent mammal victims of WVCs were wild boar Sus scrofa (31%), roe deer Capreolus capreolus (21%) and European badger Meles meles (13%), among LSM, and red fox Vulpes vulpes (27%) among SSM. In general, our results indicated that most WVCs occurred in areas with a higher number of forest patches and a higher total length of forest edge (AM, LSM), in curvy sections of the road (LSM). The number of WVCs was lower in locations covered by urbanized areas and grassland (LSM), in the sections with fences, exits and overpasses (LSM, AM). The road sections where there is a higher risk of severe collisions (involving large species) are situated in areas where the Tri-City Bypass bisects a highly forested area, which serve as movement corridors for LSM between fragmented forest complexes. We conclude that the number of WVCs can be reduced by preventing animals from accessing the road and ensuring a safe road crossing. This could be achieved by extending fencing and retrofitting some existing underpasses. [ABSTRACT FROM AUTHOR]

Roads impact wildlife through a range of mechanisms from habitat loss and decreased landscape connectivity to direct mortality through wildlife-vehicle collisions (roadkill). These collisions have been rated amongst the highest modern risks to wildlife. With the development of “citizen science” projects, in which members of the public participate in data collection, it is now possible to monitor the impacts of roads over scales far beyond the limit of traditional studies. However, the reliability of data provided by citizen scientists for roadkill studies remains largely untested. This study used a dataset of 2,666 roadkill reports on national and regional roads in South Africa (total length ~170,000 km) over 3 years. We first compared roadkill data collected from trained road patrols operating on a major highway with data submitted by citizen scientists on the same road section (431 km). We found that despite minor differences, the broad spatial and taxonomic patterns were similar between trained reporters and untrained citizen scientists. We then compared data provided by two groups of citizen scientists across South Africa: (1) those working in the zoology/conservation sector (that we have termed “regular observers,” whose reports were considered to be more accurate due to their knowledge and experience), and (2) occasional observers, whose reports required verification by an expert. Again, there were few differences between the type of roadkill report provided by regular and occasional reporters; both types identified the same area (or cluster) where roadkill was reported most frequently. However, occasional observers tended to report charismatic and easily identifiable species more often than road patrols or regular observers. We conclude that citizen scientists can provide reliable data for roadkill studies when it comes to identifying general patterns and high-risk areas. Thus, citizen science has the potential to be a valuable tool for identifying potential roadkill hotspots and at-risk species across large spatial and temporal scales that are otherwise impractical and expensive when using standard data collection methodologies. This tool allows researchers to extract data and focus their efforts on potential areas and species of concern, with the ultimate goal of implementing effective roadkill-reduction measures.

ABSTRACT: Collisions between wildlife and vehicles are detrimental to both wildlife and human safety. A variety of mitigation methods have been deployed with the intent of increasing ungulate awareness of approaching vehicles. Wildlife warning reflectors are one such method. Roadside reflectors are designed to reflect headlights into the right‐of‐way and alert ungulates to approaching vehicles. Studies of the effectiveness of these reflectors have yielded mixed results. We conducted a robust test of reflectors in central Wyoming, USA, during 2013 and 2014, and unexpectedly discovered a potentially more effective method than the reflectors for reducing collisions between vehicles and mule deer (Odocoileus hemionus). In our initial experiment, we manipulated 10 1.6‐km segments of highway by leaving their reflectors exposed or covering them with a white canvas bag with the intention of neutralizing the reflector. The treatment configuration was swapped monthly. We counted deer carcasses under each treatment for 1 year and observed deer road‐crossing behavior using thermal video cameras. Carcass rates were 33% less in the white canvas treatment relative to uncovered reflectors. Deer in the white canvas treatment also stopped before entering the road 20% more often, ran into the road from the right‐of‐way 11% less often, and fled from the road 12% more often than when reflectors were uncovered. In a follow‐up experiment, we found that deer carcass rates were 32% less when reflectors were exposed versus covered with black canvas. We further found that deer road‐crossing behavior was least risky in a white canvas treatment, intermediate in a reflectors treatment, and most risky when reflectors were removed from posts. Taken together, these results indicate that, although reflectors were moderately effective, white canvas was substantially more effective in reducing deer–vehicle collisions. This unexpected finding suggests that new vigilance‐enhancing mitigation methods should be explored as a way to reduce wildlife–vehicle collisions. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Understanding road-kill patterns is the first step to assess the potential effects of road mortality on wildlife populations, as well as to define the need for mitigation and support its planning. Reptiles are one of the vertebrate groups most affected by roads through vehicle collisions, both because they are intentionally killed by drivers, and due to their biological needs, such as thermoregulation, which make them more prone to collisions. We conducted monthly road surveys (33 months), searching for carcasses of freshwater turtles, lizards, and snakes on a 277-km stretch of BR-101 road in Southernmost Brazil to estimate road-kill composition and magnitude and to describe the main periods and locations of road-kills. We modeled the distribution of road-kills in space according to land cover classes and local traffic volume. Considering the detection capacity of our method and carcass persistence probability, we estimated that 15,377 reptiles are road-killed per year (55 reptiles/km/year). Road-kills, especially lizards and snakes, were concentrated during summer, probably due to their higher activity in this period. Road-kill hotspots were coincident among freshwater turtles, lizards, and snakes. Road-kill distribution was negatively related to pine plantations, and positively related to rice plantations and traffic volume. A cost-benefit analysis highlighted that if mitigation measures were installed at road-kill hotspots, which correspond to 21% of the road, they could have avoided up to 45% of recorded reptile fatalities, assuming a 100% mitigation effectiveness. Given the congruent patterns found for all three taxa, the same mitigation measures could be used to minimize the impacts of collision on local herpetofauna. [ABSTRACT FROM AUTHOR]

Wildlife-vehicle collisions on the roads lead to mortality of a range of animal taxa both within and around wildlife reserves. Quantifying and understanding impacts of roads on wildlife mortality are essential for identifying vulnerable taxa and suitable mitigation measures. We studied animal mortality on roads in relation to habitat and season in the Anamalai Tiger Reserve and adjoining Valparai plateau in the Western Ghats, India. Habitats were broadly classified as forest, monoculture plantations (tea, coffee, eucalyptus) and mixed. Eleven road transects of 3-12 km length were surveyed between 9 and 12 times each during monsoon (2011) and summer (2012). We recorded 2969 roadkills (mean = 2.01/km) during the 1473.4 km of road surveys carried out. The overall roadkill rate was 21.2 (± 3.87 SE) individual kills/10 km. Amphibians were most frequent in roadkills (overall roadkill rate of 9.3 ± 2.17 SE kills/10 km, n = 1307), followed by invertebrates and unidentified taxa (7.6 ± 1.81 SE kills/10 km, n = 1066). Roadkill rate was 2.4 times higher in monsoon than summer, with amphibians particularly averaging higher kill rate during monsoon. Frequency of roadkills of various animal groups differed between seasons in different habitats. In both the seasons, most roadkills were recorded mainly in tea, forest, and forest-tea habitats. Relative to length of roads through forest, a disproportionately large number of roadkills of herpetofauna and mammals were recorded in forest habitat. Higher vehicular movements, including tourist traffic, road widening, removal of native plants along roads and construction of sidewalls without breaks obstruct animal movements and may be responsible for roadkills. Designing roads to be more permeable for safe animal movement, particularly where roads pass through forest, and sensitizing highways authorities are essential to reduce animal mortality and make roads more wildlife- friendly in this region. [ABSTRACT FROM AUTHOR]

Roads can have negative impacts on wildlife through indirect effects such as fragmentation of habitat, or through direct effects such as fatal collisions with vehicles. Wildlife deaths on British roads number in the millions per year, so the resulting carcasses represent a substantial carrion biomass available as food for scavengers. By removing roadkill in urban areas, scavengers perform a valuable ecosystem service, but the rapid removal of these carcasses by scavengers could bias estimates of the impacts of roads on wildlife. In order to evaluate the scale and context of urban roadkill scavenging, we examined: (i) which species scavenge on roadkill in urban areas, (ii) the likelihood of roadkill being removed by scavengers, and (iii) whether spatial and temporal factors (habitat type and time of day) influenced the rate of removal. Camera traps baited with chicken heads as simulated 'roadkill corpses' were deployed in six residential and six parkland sites in the city of Cardiff, UK. Seven species were observed removing the roadkill, with corvids being the most common scavengers, responsible for 42% of removals. Of the 120 corpses, 90 (76%) were removed within 12 h. Time of day had a significant effect on the rate of removal, with the number of carcass removals peaking in the first few hours of daylight. Of roadkill placed at 9 am, 62% of carcasses had been removed after only 2 h. Removal of corpses by scavengers could mean that the actual number of road deaths is six times more than that observed during surveys. [ABSTRACT FROM AUTHOR]

Road mortality is identified as a threat to American badger ( Taxidea taxus (Schreber, 1777)) populations across Canada. Understanding habitat selection and movement in relation to roads is therefore vital to their conservation. Using telemetry data and road-kill locations of badgers in southwestern Ontario, we examined the relationship between habitat selection, movement patterns, and roads at three spatial scales. At the study-area scale, we assessed the effects of habitat attributes on burrow site selection. Several individuals placed their burrows closer to primary highways than expected, suggesting that badgers are not sensitive to human disturbances at this scale. Using straight-line movement trajectories between burrows, we analyzed individual movement patterns within home ranges. All badgers showed some degree of road avoidance, either crossing fewer roads or roads that posed lower mortality risk. At the road-crossing scale, we compared landscape features surrounding road-kill locations to random locations along the same roadway. There was a positive relationship between road-kill locations and number of water-based linear features and higher density of hedgerow cover. Our results provide evidence that badger movement is influenced by roads at multiple scales, which has important implications for managers interested in developing road-mitigation strategies for this endangered population. [ABSTRACT FROM AUTHOR]

The effectiveness of measures installed to mitigate wildlife road-kill depends on their placement along the road. Road-kill hotspots are frequently used to identify priority locations for mitigation measures. However, in situations where previous road mortality has reduced population size, road-kill hotspots may not indicate the best sites for mitigation., The purpose of this study was to identify circumstances in which road-kill hotspots are not appropriate indicators for the selection of the best road-kill mitigation sites. We predicted that: (i) road-kill hotspots can move in time from high-traffic road segments to low-traffic segments, due to population depression near the high-traffic segment caused by road mortality; (ii) this shift will occur earlier for more mobile species because they should interact more often with the road; (iii) this shift can occur even if the low-traffic segment runs through lower quality habitat than the high-traffic segment. To test these predictions, we simulated population size and road-kill over time for two populations, one exposed to a road segment with high traffic and the other to a road segment with low traffic., Our simulation results supported Predictions 1 and 3, while Prediction 2 was not supported., Synthesis and applications. Our results indicate that, for new roads, road-kill hotspots can be useful to indicate appropriate sites for mitigation. On older roads, road-kill hotspots may not indicate the best sites for road mitigation due to population depression caused by road mortality. Direct measures of the road impact on the population, such as per capita mortality, are better indicators of appropriate mitigation sites than road-kill hotspots. [ABSTRACT FROM AUTHOR]

• High-beam headlights increased detection probability and detection distances of deer. • The amount of time spent driving decreased detection distances of deer. • Detection probability decreased when deer were in vegetation and not at road level. • Nearly all encounters with wild pigs and small mammals were deemed dangerous. • Most drivers could not detect wildlife at safe distances to avoid a collision. Wildlife-vehicle collisions are dangerous for motorists; however, few studies have addressed driver detection of roadside animals, and none have evaluated detection of free-ranging wildlife. We used 24 volunteer drivers, infrared videography, a 75-km route, and free-ranging wildlife to quantify factors influencing (1) probability of wildlife detection, (2) detection distance, and (3) probability of dangerous encounters (i.e., detection distance < distance required for braking) for multiple species at night in South Carolina, USA. Detection probability of white-tailed deer (Odocoileus virginianus) was impacted by multiple driver, animal, and roadside factors. Deer detection distances increased by 20.99 m when drivers used high-beam headlights and 23.36 m when deer were moving but decreased by 0.71 m for every minute into a drive. Every encounter with wild pigs (Sus scrofa) and most encounters with small mammals were considered dangerous. Our findings suggest most drivers cannot safely detect deer, wild pigs, and small mammals at night. [ABSTRACT FROM AUTHOR]

Wildlife warning signs are the most commonly used and widespread form of road impact mitigation, aimed at reducing the incidence of wildlife–vehicle collisions. Evidence of the effectiveness of currently used signs is rare and often indicates minimal change in driver behaviour. Improving the design of these signs to increase the likelihood of appropriate driver response has the potential to reduce the incidence of wildlife–vehicle collisions. This study aimed to examine and assess the opinions of drivers on wildlife warning sign designs through a public opinion survey. Three currently used sign designs and five alternative sign designs were compared in the survey. A total of 134 drivers were surveyed. The presence of temporal specifications and an updated count of road-killed animals on wildlife warning signs were assessed, as well as the position of the sign. Drivers’ responses to the eight signs were scaled separately at three speed limits and participants indicated the sign to which they were most likely to respond. Three signs consistently ranked high. The messages conveyed by these signs and their prominent features were explored. Animal-activated and vehicle speed-activated signs were ranked very highly by participants. Extensive field trials of various sign designs are needed to further this research into optimizing wildlife warning sign designs.

Collisions with large ungulates cause serious human and animal injuries and significant property damage. Therefore, wildlife crossing structures are increasingly included in new road construction to reduce wildlife–vehicle collisions, while still allowing wildlife to safely cross roads. Recently, state and federal transportation budgets have declined, concomitantly reducing the construction of wildlife crossing structures, which are generally tied to large-scale reconstruction projects that are delayed for decades into the future. Nevertheless, even during times of fiscal constraint or temporal delay, it is still necessary to reduce collisions with wildlife and maintain habitat connectivity. Therefore, it is important to find cost-effective and functional alternatives. Retrofitting roadways with wildlife exclusion fencing that directs animals to existing highway structures (e.g., sufficiently sized bridges and culverts) is a possible cost effective, interim solution that needs further testing. Along Interstate-17 in northern Arizona, we heightened 9.17 km of right-of-way barbed wire fence to 2.4 m to guide elk (Cervus canadensis) to 2 large bridges and 2 modified transportation interchanges. We evaluated occurrence of elk–vehicle collisions, elk use of existing structures, and GPS movements of elk pre- and post-fencing retrofit. Post retrofit, there was a 97% reduction in elk–vehicle collisions for the 9.17 km stretch of road. There were also no increases in collisions at the fence termini (area within 1.61 km from fence ends) nor in the remaining sections, indicating that elk were not simply forced to those areas. We documented a 217% and 54% increase in elk use of the 2 large bridges, but no elk use of the transportation interchanges. GPS relocation data from 31 elk showed a statistically insignificant decrease, from 0.07 to 0.03 crossings per approach pre- and post-fence modification, respectively. Elk road crossings, determined through GPS relocations, were concentrated around the bridge structures rather than being evenly distributed across the treatment sections, and similar to collisions, crossings did not increase on adjacent fence termini. Using the Huijser et al. (2009) estimate of $17,483 for the cost to society of an elk–vehicle collision, the level of collision reduction on this stretch of road will recoup project costs inthat, under certain circumstances, retrofits can in the short-term reduce wildlife–vehicle collisions on roadways that are not scheduled to be reconstructed in the near future. However, for the long-term, areas with significant wildlife– vehicle collisions or habitat fragmentation should have appropriately designed, located, and maintained wildlife crossings with exclusionary funnel fencing.

This study examined whether the rising trends of wild boar (Sus scrofa)-vehicle accidents in Sweden are accompanied by a higher amount of personal injuries and costs. Temporal trends in accident frequencies and the number of persons injured in wild boar-vehicle accidents were examined for 2003⁻2016, and the cost of wild boar-vehicle accidents was calculated. Results show increases in the number of personal injuries, and increased costs, particularly after 2010⁻2012. The total number of wild boar accidents correlated with the number of injured persons as well as with the number of accidents with personal injuries. Approximately one person (1.13%) is injured per 100 wild boar-vehicle accidents, and approximately one accident per 200 wild boar-vehicle accidents will result in one or more persons with injuries (0.5%). However, most of the persons injured have slighter injuries. Although the number of wild boar-vehicle accidents and the number of persons injured in the accidents have increased, the frequency of accidents resulting in personal injuries is still at low levels in comparison with, for example, frequencies of personal injuries for moose accidents. The cost for wild boar-vehicle accidents has increased between 2003 to 2016 and is currently estimated to vary between approximately EUR 9.66⁻12.31 million per year.

Context. Brazil has one of the richest biodiversity and one of the most extensive road networks in the world. Several negative impacts emerge from this interaction, including wildlife-vehicle collisions (WVC), which may represent a significant source of non-natural mortality in several species. The understanding of the main drivers of WVC is, therefore, crucial to improve the safe coexistence between human needs (transportation of goods and people) and animal populations. Aims. We aimed to (1) evaluate the relative influence of land-cover patterns on the distribution of WVC, (2) assess whether WVCs are clustered forming hotspots of mortality, and, if so, (3) evaluate the benefits of mitigating only hotspot sections. Methods. We collected WVC data involving medium-large mammals (4-260 kg) along three road transects (920 km), fortnightly over 1 year (n = 1006 records). We used boosted regression trees to relate the WVC locations with a set of environmental variables including a roadkill index, reflecting overall habitat suitability and landscape connectivity, while accounting for spatial autocorrelation effects. We identified hotspots of mortality using Ripley's K statistic and testing whether data follow a random Poisson distribution correcting for Type I error. Key results. We found a strong association between WVC probability and roadkill index for all focal species. Distance to riparian areas, tree cover, terrain ruggedness and distance to urban areas were also important predictors, although to a lesser extent. We detected 21 hotspots of mortality, yet with little spatial overlapping as only four road sections (2%) were classified as hotspot for more than one species. Conclusions. Our results supported that WVC mainly occur in road sections traversing areas with more abundant and diverse mammal communities. Hotspots of mortality may provide important information to prioritise road sections for mitigation, but this should be used in complement with roadkill indexes accounting for overall mortality. Implications. The results support focusing on hotspots and habitat quality and landscape connectivity for a better assessment of road mortality. At the local scale, a larger number and improved road passages with exclusionary fencing of appropriate mesh size in riparian areas may provide safe crossings for many species and constitute a promising mitigation measure. [ABSTRACT FROM AUTHOR]

The magnitude, composition, temporal and spatial patterns of mammal road mortality were assessed along some sections of two different road types (I/51 and R1) connecting the towns of Banská Bystrica, Zvolen and Banská Štiavnica (Central Slovakia). Road kills were surveyed using a car, three or four times per week from March 2008 to December 2012. We conducted 440 surveys, traveling a total of 39,700 km, and recorded 5,416 road mortality events (120 kills per km on average). Mammals were represented by 693 individuals (12.8% of the total number of carcasses) identified into 20 species and categories, respectively. The most frequently identified species were fox, hedgehog and domestic cat, a substantial part fell into the category of small mammals, as they could not be mostly identified to a genus. We found significant temporal and spatial differences in the magnitude of road-kills and identified several road segments as mortality hotspots both for all observations and for each season. Using logistic models we found significant relationships between the number and composition of the mammal casualties and higher proportion of arable land, built-up areas and roads in the landscape bordering the roads. Road topography was found to be among the important variables in explaining road-kills as carnivores were most susceptible to be killed on the raised segments and insectivores and herbivore mammals on the raised or buried segments of the roads. Construction of the fence along the R1 expressway in 2010 was related to significant decrease in road-kills, however, significantly higher mortality level was recorded at the segments with the underpass where streams with line riparian vegetation are crossed by the road. This effect was not identified at segments with expressway feeders. This finding suggests that the line vegetation continues to serve as migration corridor and leads animals to the R1 road where they find defects in fencing and try to cross through them and enter the road. [ABSTRACT FROM AUTHOR]

Roads have important effects on wildlife, such as natural habitat fragmentation and degradation and direct killing of fauna, which leads to reductions in wildlife population size. We focused on a principal road in Northwest Argentina to test for the effect of seasonality and landscape features on the composition of road-killed wildlife. We conducted regularly scheduled road trips during the dry and wet seasons. We recorded the presence or absence of a vegetation curtain or hedge along the road. We measured land use by remote sensing in a 500 m buffer along the road. We compared the abundance of animals killed between seasons (dry and wet) for different taxonomic groups (mammals, birds and reptiles) and for different origins (domestic and native). We built linear mixed models to test the effect of landscape features on the abundance of killed animals. Two hundred and ninety-three individuals were killed, belonging to 35 species; 75.8 % were native and 24.2 % domestic species. The majority of animals killed were mid-sized mammals. More animals were killed during the dry season. The most important factors to explain the wildlife road-killing were the season and the proportion of agricultural landscape. The composition of the killed animals changed with the season. The proportion of agricultural landscape incremented the number of killed birds and mammals during both seasons, without affecting reptiles. The ratio of wild to domestic animals killed was dependent on the season. This study sets a precedent as the first in road ecology in Northwest Argentina and should be taken into account for road planning and regulation. [ABSTRACT FROM AUTHOR]