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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]

The development of transportation infrastructure has been identified as one of the main pressures on biodiversity. The effects of transport infrastructure are more documented for terrestrial mammals, birds and amphibians than for bats. To assess the impacts of roads on bat activity, we carried out full-night acoustic recordings of bat calls at 306 sampling points at different distances from a major road at three study sites in France. To assess the relationship between bat activity and the distance to the major road, we performed generalized linear mixed model analyses for thirteen different species or groups and additionally explored the non-linear effect with generalized additive mixed models. Our results showed that low-flying species are more affected than high-flying species. Indeed, we found a significant negative effect of major roads on bat activity for the 'clutter-adapted' species, Eptesicus serotinus , Myotis spp., Pipistrellus pipistrellus and Rhinolophus hipposideros. These results demonstrate that the road-effect zone of major roads extends up to five kilometres. Extrapolating those road-effects zones to the major roads in the European Union, we estimated that 35% of the European Union is potentially negatively impacted. Finally, it seems urgent to consider these road effects with the cumulative effects of other roads by improving habitat connectivity and foraging areas in land use policies. Additionally, to implement drastic conservation practices for species of conservation concern in environmental impact assessment studies, efficient mitigation and offset measures implemented should be sized proportionally to the disturbance caused. • Major roads affect activity in five of the thirteen studied taxa. • Low-flying species are more affected than those that fly in the open. • Road impacts may be due to road kills, traffic disturbance and ruptured connectivity. [ABSTRACT FROM AUTHOR]

Abstract Road mortality may contribute to the population decline of eastern monarch butterflies (Danaus plexippus L.). We estimated autumn monarch roadkill rates within the primary Oklahoma to Mexico southern migration corridor (i.e., Central Funnel). Dead monarchs were surveyed along Texas roadsides during four weeks of autumn migration in 2016 and 2017. Roadkill averaged 3.4 monarchs per 100 m transect, reaching 66 per 100 m in a roadkill hotspot in southwestern Texas. Extrapolations of Central Funnel roadkill based on survey data and road types were 3.6 and 1.1 million in 2016 and 2017, respectively. Spatial distribution of roadkill across the Central Funnel was projected from Texas survey data using 30 m resolution MaxEnt niche models. Highest roadkill probability was linked to arid climate and low human population density. The latter variables may not be directly related to roadkill, but instead represent indirect correlates of increased densities of monarchs where the migration corridor narrows southwards. The higher roadkill projected in southwest Texas and Mexico by MaxEnt models agrees with previously reported monarch roadkill hotspots. MaxEnt-based 2016–2017 projections for annual roadkill rates throughout the Central Funnel averaged 2.1 million. This figure is similar to the result by simple extrapolation, and represents about 3% of the overwintering monarch population for these years. Mitigation at roadkill hotspots in the Central Funnel could reduce monarch roadkill mortality during migration and contribute towards conservation efforts for the monarch butterfly. Graphical abstract Unlabelled Image Highlights • Texas autumn monarch roadkill averages 3.4/100 m, reaching 66/100 m in hotspots. • Central Funnel estimated roadkill ranged from 0.2 to 2 million in 2017 and 2016. • MaxEnt projected 1.3 million overall roadkill, mainly in West Texas and Mexico. • Central Funnel roadkill may represent 2–3% of monarch overwintering population. • MaxEnt models can guide mitigation efforts needed to reduce monarch roadkill. [ABSTRACT FROM AUTHOR]

Abstract Road networks can have serious ecological consequences for many species, mainly through habitat fragmentation and mortality due to collisions with vehicles. One example of a species impacted by roads is the giant anteater (Myrmecophaga tridactyla), currently listed as Vulnerable by IUCN. Here we analysed the relative effect of fragmentation and mortality due to roads on giant anteater populations and show the critical areas for their persistence in Brazil. We estimated minimum patch size and maximum road density to evaluate the impact of the road network and observed road-kills on this species. We explored different scenarios by varying values of dispersal capacity to estimate the minimum patch size, and also of population densities to estimate maximum road density for giant anteater persistence. Our findings indicated that the minimum patch size can be from 498 to 247 km2 and the maximum road density can vary between 0.21 and 0.55 km/km2 in pessimist and optimistic scenarios, respectively. In Brazil, habitat fragmentation seemed to have a major impact over giant anteater populations. Habitat fragmentation due to roads seemed to have a more negative effect than mortality due to collisions with vehicles. Critical areas for the species persistence can represent 32% of its range in the optimistic scenario with 18% of suitable patches below the minimum size and 0.1% above the maximum road density. This study provides insights and implications for road networks on giant anteater populations in Brazil and guidance on road density and patch size thresholds for land managers and road agencies charged with planning ecologically sustainable roads in Brazil. Highlights • Habitat fragmentation can be more detrimental than road-kills. • Between 18% and 21% of suitable habitat is below the minimum patch size. • Between 0.1% and 1% of species range is above the maximum road density. • Critical areas for species persistence represent 32–36% of the species range. • Conservation opportunities exist in northern areas while southern needs mitigation. [ABSTRACT FROM AUTHOR]

Across the world, many wildlife studies rely on data collected by volunteers. Roadkill studies often rely on data collected by non-experts including road maintenance personnel and volunteers, but data quality control is rarely applied. We investigated whether maintenance personnel correctly identified the species of road-killed mammals along toll roads in São Paulo State, Brazil. We investigated 3222 images of road-killed animals and compared the original species descriptions by road maintenance personnel (non-experts) with our identification (experts). We also presented images of alive and road-killed mammals to road maintenance personnel (n = 179) and asked them to describe the species. We found that road maintenance personnel typically correctly identified certain common, large, or highly recognizable species. However, rare or rarely seen species, species that resemble other species (e.g. small wild canids and felids), or species that are not highly recognizable were often misidentified, ambiguously described, or not identified at all. We also found that the ability of road maintenance personnel to correctly identify the most common road-killed small wild canids and felids is dependent on the context. When similar species are rare, road maintenance personnel typically correctly identifies the most common road-killed small wild canids and felids. However, common small canids and felids are not reliably identified if similar species are more abundant. To improve the reliability of species identification by non-experts, we recommend training in species identification, including images with a scale to accompany all roadkill records, and verification of the roadkill records and associated images for selected species by experts. [ABSTRACT FROM AUTHOR]

We present a system for state-wide evidence of animal-vehicle collisions (AVC). The primary part of this system is a geographic database which is connected to a web-map application. AVC data come from the Police via an online system of traffic incidents (JSDI) and from volunteers through a web or mobile interface. Data are processed using automatic scripts which identify data errors and perform spatial analyses. The application automatically computes AVC hotspots every midnight and crash densities along road sections. Hunter area administrators consequently have an overview of their areas. More than 40,000 records are currently included in this database. 50% of them were added over the last two years when it was launched. The majority of data (90%) came from JSDI. The species is known for 44% of JSDI records. The majority of the identified species were roe deer (75%), followed by wild boar (15%). Roe deer crashes occur most frequently in May within 2 h after sunset. 32.5% (56.4%) of these crashes occur within 1 h (2 h) before or after sunset or sunrise. For wild boar, the values are less distinctive (19.4% and 37.7%). Approximately 1800 AVC hotspots, which cover 0.5% of the Czech road network, were detected and visualized on a map. [ABSTRACT FROM AUTHOR]

The rapidly expanding global road network poses threats to wildlife, including direct mortality. Given limited knowledge and resources, strategic allocation is critical. We introduce a method to identify areas and taxa affected by vehicle collisions as priorities to study and protect. The method is illustrated using Latin America as a case study. In this region high biodiversity and an expanding road network can result in high impacts from roads, yet emerging research expertise offers opportunities for action. To identify priority targets, we combined predicted spatially-explicit roadkill rates for birds and mammals with information about the current road network and species conservation status. Priority areas for conservation (with many species susceptible to roadkill but few or inexistent roads) were largely concentrated in the Amazon, while priority areas for research (unstudied regions with many roads and many species susceptible to roadkill) occur in various areas from Southern Mexico to Chile. Priority taxa for conservation reflected studied, roadkill-susceptible groups (e.g., vultures and armadillos), while priority taxa for research were defined as either poorly-studied roadkill-susceptible groups or unstudied groups of conservation concern (e.g., cuckoos and shrew opossums). Our approach offers a tool that could be applied to other areas and taxa to facilitate a more strategic allocation of resources in conservation and research in road ecology. • Roadkill data and traits define areas and species for protection and research. • Future road developments in the Amazon could be devastating for biodiversity. • Research on road impacts are urgently needed in Central America and northern South America. • Vultures, armadillos, cuckoos and shrew opossums need more protection and research. • Our new framework can guide the allocation of resources for conservation and research. [ABSTRACT FROM AUTHOR]

Estimates of detectability and removal of carcasses have been determined for vertebrates but not for invertebrates, although the latter are more frequently killed on roads. The aim of this study was to estimate the detectability and persistence of road-killed butterflies and to assess the relative contributions of the location on the road, volume of traffic, and presence of scavengers to the removal of dead butterflies. During three independent experiments, dead butterflies from 12 species were placed at randomly chosen locations along selected road sections (both on asphalt and on a verge) with varying vehicle traffic volume (including sections without vehicles) and scavenger abundance. Dead butterflies were counted, scavengers' behaviour was observed, and the traffic volume was measured. The detectability was higher for butterflies placed on asphalt (0.979) than on a verge (0.767) and increased with body size. The removal rate of dead butterflies from asphalt on roads with vehicles was four times faster (persistence probability of 12 h: 0.139) than on roads where vehicles were absent (persistence probability: 0.508). Overall, only 5% of butterflies persisted for a 48-h period. Vehicles and bird scavengers removed 14.9% and 9.6% of dead butterflies, respectively. The probability of dead butterfly removal by birds was positively correlated with traffic, indicating that the number of road-killed butterflies might be substantially underestimated on roads with high traffic. This shows that imperfect detection should be taken into account when estimating the number of road-killed butterflies, especially for butterflies on road verges. [ABSTRACT FROM AUTHOR]

Vehicles kill many wild animals worldwide, including in protected areas, where the impacts of roads are increasing due to road development, the rise of human population at their boundaries, and the growing interest in wildlife tourism. Yet, knowledge on the factors influencing wildlife roadkills within protected areas is limited, particularly for large carnivores. Here, we investigated spotted hyena (Crocuta crocuta) roadkills inside a protected area, the Serengeti National Park, Tanzania, between 1989 and 2023 (n = 104). We examined spatial determinants of hyena roadkills using a generalized linear model, temporal and spatiotemporal patterns in hyena roadkills, and the effect of age, sex, and social status on hyena mortality due to vehicles. Roadkills were more likely on main roads and the locations and number of roadkills varied according to seasonal changes in the locations of vast migratory ungulate herds, which are the main prey of hyenas. Adult females, who travel the most to forage on these herds, suffered the highest levels of road mortality. Road mortality was independent from social status among females. Our results indicate that roadkill patterns were shaped by both road characteristics, as incidence was substantially higher on main roads, and large-scale seasonal changes in the location of migratory prey. Further, the incidence of hyena roadkills was exacerbated by long-distance 'commuting' trips to areas containing large aggregation of migratory herbivores. Our findings provide new insight on ecological and individual factors modulating roadkill incidence in a large carnivore. [ABSTRACT FROM AUTHOR]

Expanding road networks in the wildland-urban interface may increase wildlife mortality from vehicle collisions. However, our knowledge of long-term roadkill rates and impacts on vertebrate populations is poor. We capitalized on a 31-year study to determine how roadkill rates varied with demography and traffic volume in a population of golden-mantled ground squirrels (Callospermophilus lateralis ; GMGS) along 1 km of rural road in Colorado, USA. Despite low annual numbers of roadkill events (0–7 GMGS), adult female mortality was high (10.9 %) and increased with female cohort size. Adult roadkill rates increased with our traffic volume index. We estimate 71 % of roadkill events would have been undetected if we performed weekly instead of daily surveys. Hence, population-level impacts of road mortalities are likely underestimated in short-term studies that lack paired demographic data. Understanding true rates of roadkill in wildland and developing areas will help inform conservation strategies. [ABSTRACT FROM AUTHOR]

The koala ( Phascolarctos cinereus ), one of the world's most iconic faunal species, was recently listed under Australian government legislation as vulnerable in the northern states of Queensland and New South Wales and in the Australian Capital Territory, but not in the southern states of Victoria and South Australia. This review synthesises empirical evidence of regional koala population trends, their conservation outlook, and associated policy challenges. Population declines are common in the northern half of the koala's range, where habitat loss, hotter droughts, disease, dog attacks and vehicle collisions are the major threats. In contrast, some southern populations are locally overabundant and are now subject to managed declines. The koala presents the problem of managing a wide-ranging species that now primarily occurs in human-modified landscapes, some of which are rapidly urbanising or subject to large-scale agricultural and mining developments. Climate change is a major threat to both northern and southern populations. The implementation of policy to conserve remaining koala habitat and restore degraded habitat is critical to the success of koala conservation strategies, but habitat conservation alone will not resolve the issues of koala conservation. There needs to be concerted effort to reduce the incidence of dog attack and road-related mortality, disease prevalence and severity, and take into account new threats of climate change and mining. Many of the complex conservation and policy challenges identified here have broader significance for other species whose population trends, and the nature of the threatening processes, vary from region to region, and through time. [ABSTRACT FROM AUTHOR]

Road-kill is the most recognized impact of traffic and an important threat for biodiversity. Nevertheless, most research on this topic deals with particular species or with road features, describing proximate correlates and rarely making inference on the mechanisms. Here we provide a more general approximation by describing life-history, temporal and spatial factors affecting vertebrate road-kills in Mediterranean landscapes, which are a biodiversity hotspot with little studied road impacts. During one year we recorded the casualties found on paved roads within Doñana Natural Park. We found 2368 road-kills belonging to 66 species (32% of the study area checklist), with abundant ectotherm species more likely to be road-killed. We also investigated the temporal and spatial factors affecting the road-kill patterns of different taxonomic and functional groups. The phenology of the species was the main factor affecting road-kill temporal patterns for lizards, all birds and small mammals. Additionally, rainfall events were associated with the road-kill peaks of wintering birds, whereas high temperatures were related to the increase of road-killed snakes and the decrease of road-killed amphibians. Amphibians, snakes, lizards and small passerines were mainly road-killed according with their spatial abundance. Mitigation measures such as wildlife road-crossing structures showed contradictory effectiveness for small vertebrates due to the lack of adequate drift fences. We suggest prioritizing the mitigation measures which can permanently decrease the risk of been road-killed for ectotherm species, such as specific road-crossing structures with effective drift fences on road-kill hotspots. Concurrently, group-specific temporal mitigation measures should be applied during the road-kill seasonal peaks. The present work provides recommendations to decrease road-kill impacts in Mediterranean environments, but simultaneously tries to contribute to a more general development of road ecology research, suggesting several useful guidelines to perform road-kill studies. [ABSTRACT FROM AUTHOR]

Collisions with cars are an important mortality factor for many wild animals. Measures to mitigate road mortality are costly so should be implemented using cost-effective measures in locations where the road mortality is consistently highest and non-random in different species. It is thus important to identify what features causes these biodiversity collision blackspots. Almost all of the data and literature on collisions refer to vertebrates with little known about invertebrates. We used data on butterfly roadkills in three large landscape plots in Poland to identify sites where the collision rate seems to be routinely high. Biodiversity collision blackspots were identified from occurrence in successive years using spatial hierarchical clustering. Biodiversity collision blackspots comprised just 4% of the total road length, but included 49% of all road-killed butterflies. Habitats within 500 m of each blackspot was compared to random non-blackspot sites using generalized linear mixed models. The occurrence of blackspots was linked with high traffic volume, but only when cover of grassland in a landscape was high and verges had low plant species richness. Similarly, blackspots occurred with high probability when traffic volume was high but especially if grassland cover in the landscape and verge mowing frequency were also high. These blackspots had higher species richness and abundance of butterflies in the surrounding landscape than in random sites. Biodiversity collision blackspots analysis identified road sections of high road mortality for different butterfly species. Moreover, blackspots were also indication of species rich areas of conservation concern that were intersected by roads. Thus, conservation practitioners may direct mitigation measures, such as less frequent mowing and speed limit, in a cost-efficient manner in these spatially-limited locations. [ABSTRACT FROM AUTHOR]

Managing road verges to promote diverse and flower-rich plant communities has been proposed to mitigate the decline of pollinating insects caused by the loss of natural and semi-natural habitat. There is, however, a concern that flower-rich road verges can be ecological traps for pollinators as insects might be attracted to a habitat where there is a risk that they are killed by traffic. Therefore, we investigated the combined effects of traffic intensity and flowering plant diversity in road verges on the mortality and behaviour of bumblebee queens. The probability that an observed bumblebee queen was dead almost quadrupled when traffic increased from 100 to 6000 vehicles per day and tended to be lower when the flowering plant diversity in the road verge was high. Further, the number of nest-seeking bumblebee queens decreased dramatically with increasing traffic intensity in sites with low diversity of flowering plants, but not in sites with high diversity. Based on published data on bumblebee colony densities in different habitat types, we estimate that between 0.2 % and 32 % of all bumblebee queens present in our study landscapes were killed by traffic. We conclude that the flowering plant diversity in the road verge neither mitigates nor exacerbates the mortality from traffic. Road verges often provide pollinators with a high abundance of resources in florally poor landscapes. We therefore advise management to prioritise plant diversity along roads with low traffic intensity. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied the factors that make birds and mammals vulnerable to being killed by vehicles. [•] We found that diet influences the propensity to be killed by vehicles. [•] Omnivorous mammals and herbivorous birds are particularly vulnerable. [•] Mitigation should target these types of species. [Copyright &y& Elsevier]

Abstract: Little is known of the impact of roads on insect mortality. This is a significant gap, because road verges are regarded as an important tool for insect conservation. In this study, we investigated which factors affect the number of roadkills in grassland butterflies and, simultaneously, the species composition and abundance on road verges. We established sixty transects, two hundred metres long, on roads in farmland areas and with differing traffic volume. Each transect consisted of two parallel lines, one on either side of the road. Ordination methods showed that the species composition of the butterflies killed on the roads was primarily explained by the species composition of those living on the road verges. At least 6.8% of the butterflies were estimated to end up roadkilled. Also, the number of species and abundance of butterflies killed on the roads were positively dependent on both the abundance of butterflies on the road verges and on the traffic volume, but negatively correlated with the richness of plant species on the road verges. However, the proportion of individuals killed was negatively linked with the abundance of butterflies on the road verges, the richness of the plant species and the share of grassland in the landscape. There was a statistically significant tendency for small-bodied species to be overrepresented in the roadkill samples. Our results indicate that the verges which were of high conservation value for butterflies suffered the least from road mortality. The sowing of plant species, less frequent mowing and maintaining a high grassland cover in the vicinity of roads are recommended conservation actions for the improved conservation value of road verges for butterflies. [Copyright &y& Elsevier]

Abstract: The relatively low population size and long adult lifespan of dragonflies (Odonata, Anisoptera) makes them one of the few non-vertebrate groups likely to be impacted by direct roadway mortality. We studied adult dragonfly mortality and behavior associated with roadways for a number of species. Daily mortality rates for dragonflies were estimated from standardized surveys along predetermined lengths of roads. Relative abundance and flight behavior around and across roadways, a potentially important mortality factor, was determined from timed roadside observations. Observed flight behavior provided no evidence that roads act as significant barriers to dispersal for adult dragonflies. Estimated mean number killed ranged from 2 to 35 dragonflies/km/day. Species varied greatly in their susceptibility to motor vehicles. Two species (Plathemis lydia and Libellula luctuosa) made up more than 70% of the dead dragonflies collected, but only represented 14% and 31% of live dragonflies observed, respectively. The relatively low flight heights of these two species over roads (typically under 2m) may explain their susceptibility; however, another common species (Tramea lacerata) also exhibited low flight height but did not experience high mortality, possibly because of its increased flight agility. Large numbers of adult dragonflies were killed over the entire flight season by motor vehicle collisions, exhibiting the need for assessing the long-term impact of roadway mortality on dragonfly population dynamics. [Copyright &y& Elsevier]

Many carnivores have been seriously impacted by the expansion of transportation systems and networks; however we know little about carnivore response to the extent and magnitude of road mortality, or which age classes may be disproportionately impacted. Recent research has demonstrated that wildlife–vehicle-collisions (WVC) involving carnivores are modulated by temporal and spatial factors. Thus, we investigated road mortality on a guild of small and medium-sized carnivores in southern Portugal using road-kill data obtained from a systematic 36 months monitoring period along highways (260km) and national roads (314km) by addressing the following questions: (a) which species and age class are most vulnerable to WVC? (b) are there temporal and/or spatial patterns in road-kill? and (c) which life-history and/or spatial factors influence the likelihood of collisions? We recorded a total of 806 carnivore casualties, which represented an average of 47ind./100km/year. Red fox and stone marten had the highest mortality rates. Our findings highlight three key messages: (1) the majority of road-killed individuals were adults of common species; (2) all carnivores, except genets, were more vulnerable during specific life-history phenological periods: higher casualties were observed when red fox and stone marten were provisioning young, Eurasian badger casualties occurred more frequently during dispersal, and higher Egyptian mongoose mortality occurred during the breeding period; and (3) modeling demonstrated that favorable habitat, curves in the road, and low human disturbance were major contributors to the deadliest road segments. Red fox carcasses were more likely to be found on road sections with passages distant from urban areas. Conversely, stone marten mortalities were found more often on national roads with high of cork oak woodland cover; Egyptian mongoose and genet road-kills were found more often on road segments close to curves. Based on our results, two... [Copyright &y& Elsevier]

Prioritizing sites for localized mitigation measures, and forecasting the effect of interventions on an endangered population, requires an understanding of the spatial scales at which threat processes operate. Road mortality is among the greatest threats to semi-terrestrial freshwater turtles due to the group’s life-history traits. Declining throughout much of their range, spotted (Clemmys guttata) and Blanding’s turtles (Emydoidea blandingii) are exposed to high road densities and traffic volumes in the northeastern United States. We examine the distribution of roadkill risk for spotted and Blanding’s turtles at three spatial scales. Tortuosity during upland movements was used to predict road-crossing locations at the single-movement scale. A gravity model of wetland-to-wetland interactions was then developed to identify road mortality hot spots at a broader road segment scale. Finally, road-crossing risk was assessed at the scale of focal areas that support distinct populations, using a population viability analysis to evaluate the consequences of road mortality on resident populations. The observed spatial variability of road mortality risk was high for single road crossing movements, limiting the effectiveness of static mitigation measures conducted at this scale. At the broader road segment scale, road mortality hotspots were evident. The demographic risk associated with roads varied widely among discrete populations, with probabilities of extinction over 100-year projections reaching 5.1% for spotted turtles, and 58.8% for Blanding’s turtles. We conclude that conservation interventions are most likely to be effective in mitigating the effects of road mortality when implemented at the road segment and population scales. [Copyright &y& Elsevier]

Knowledge of the relationship between wildlife and roads is important for management of wildlife–vehicle collisions, which represent a serious threat to many wildlife populations and to human life and property. Effective reduction of these threats requires identification of variables influencing collision locations, and the use of these variables in spatially-explicit predictive models. We used Penrose distance modeling and 61 confirmed bobcat (Lynx rufus) road mortality locations in southern Illinois, USA, to demonstrate a rapid and accurate technique for the spatial mapping of wildlife–vehicle collision risk. We used the Penrose distance statistic to quantify the similarity between the mean multivariate habitat signature at bobcat-collision areas and road sections throughout the study area. Habitat variables assessed included road-related variables (e.g., traffic volume) and land cover characteristics (e.g., mean patch area of the landscape). Bobcat-collision areas were characterized by smaller, less-clustered habitat patches and more, large independent patches of grass cover than were study area roadway sections in general. As expected for a generalist carnivore in highly-suitable habitat, risk mapping indicated that large sections of the roaded landscape had high similarity to bobcat-collision areas. Unlike other modeling techniques used to identify risk of road mortality, our method requires little field data collection and relies on readily available digital spatial data. This technique can be used by wildlife managers and road planners, and may be particularly important in reduction of road mortality for species such as the Iberian lynx (Lynx pardinus), Florida panther (Puma concolor coryi), and Texas ocelot (Leopardis pardalus), which exist in small populations fragmented by development, and are limited by road mortalities. [Copyright &y& Elsevier]

Roads negatively affect animal populations by presenting barriers to movement and gene flow and by causing mortality. We investigated the impact of a secondary road on a population of black ratsnakes (Elaphe obsoleta) in Ontario, Canada by radio-tracking 105 individuals over 8 years. The road was not a significant barrier to movement and none of the reproductive classes examined (male, non-reproductive female, reproductive female) avoided crossing the road. However, the road was a significant source of mortality. From a total of 115 road crossings by radio-implanted snakes, 3 individuals were killed by cars, resulting in a mortality rate of 0. 026 deaths per crossing. We multiplied this mortality rate by the total number of expected road crossings by all individuals in the population in an active season (340) to estimate the number of road kills (9 individuals) each year. This estimate was higher than the actual number of road kills found, but half the number estimated from road kill models. Population viability analysis revealed that our estimate of road mortality was enough to increase the extinction probability for this population from 7. 3% to 99% over 500 years. Road mortality of more than 3 adult females per year increased the extinction probability to >90%. Our results strengthen the view that road mortality can have a pronounced negative effect on populations of long-lived species. [Copyright &y& Elsevier]

Humans have transformed most landscapes across the globe, forcing other species to adapt in order to persist in increasingly anthropogenic landscapes. Wide-ranging solitary species, such as wild felids, struggle particularly in such landscapes. Conservation planning and management for their long-term persistence critically depends on understanding what determine survival and what are the main mortality risks. We carried out the first study on annual survival and cause-specific mortality of the European wildcat with a large and unique dataset of 211 tracked individuals from 22 study areas across Europe. Furthermore, we tested the effect of environmental and human disturbance variables on the survival probability. Our results show that mortalities were mainly human-caused, with roadkill and poaching representing 57% and 22% of the total annual mortality, respectively. The annual survival probability of wildcat was 0.92 (95% CI = 0.87–0.98) for females and 0.84 (95% CI = 0.75–0.94) for males. Road density strongly impacted wildcat annual survival, whereby an increase in the road density of motorways and primary roads by 1 km/km2 in wildcat home-ranges increased mortality risk ninefold. Low-traffic roads, such as secondary and tertiary roads, did not significantly affect wildcat's annual survival. Our results deliver key input parameters for population viability analyses, provide planning-relevant information to maintain subcritical road densities in key wildcat habitats, and identify conditions under which wildcat-proof fences and wildlife crossing structures should be installed to decrease wildcat mortality. • Understanding survival is crucial for effective species conservation. • We studied survival and cause-specific mortality of European wildcat across Europe. • 83% of wildcat annual mortality was caused by humans. • Roadkill was the main source of mortality for the wildcat in Europe. • Survival decreased with increasing density of high-traffic roads. [ABSTRACT FROM AUTHOR]

Roads are one of the most prevalent threats to wildlife because they fragment landscapes and increase mortality. In response to the threat of roads to population persistence, road-effect mitigation strategies are increasingly common, typically as a combination of exclusion fencing to reduce mortality and crossing structures to enhance connectivity. To evaluate the success of mitigation structures at reducing road mortality of amphibians and reptiles, we conducted a six year paired Before-After-Control-Impact (BACI) experiment. We used road surveys to estimate the effectiveness of exclusion fencing, and a combination of hoop trapping, passive integrated transponder tag scanners and camera traps to evaluate connectivity structure effectiveness. Exclusion fencing reduced the number of turtles and amphibians on the road but had no effect for snakes. Cameras recorded 54 turtles, 72 snakes, 615 frogs, and 271 salamanders using tunnels. PIT tag scanners detected similar usage by turtles (55 uses; 24 unique individuals) and snakes (69 uses; 15 unique individuals). Tunnel usage was neither spatially nor demographically biased, indicating that the tunnels were likely to be broadly used by the local species assemblage. Crossing rates of tagged individuals suggest ~5–15% of turtles and 44% of snakes are using crossing structures. We contextualized crossing rates with population size estimates for painted and snapping turtles in the surrounding habitats. Our study is one of the first of its kind to incorporate both a robust BACI design and the context of population-level effects to demonstrate the efficacy of road-effect mitigation for protecting wildlife, especially for reptiles and amphibians. [Display omitted] • Six-year paired BACI design was used to evaluate road-effect mitigation. • Exclusion fencing reduced the number of turtles and amphibians found on the road. • No effect of exclusion fencing on the number of snakes found on the road. • Evidence that crossings are used by snakes and turtles at the population level. • First study to use multi-year BACI and study road-effects at population level [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Poaching activity has been described in the literature as harmful due to impacts on biodiversity, especially in protected areas. Although the main reason for this activity is subsistence, in many regions motivation goes beyond the limits of food necessity. We applied single-species, single season occupancy models to evaluate the spatial distribution of poachers and identify potential poaching hotspots in a mosaic of protected areas in the Caatinga domain, northeastern Brazil. We used camera-traps over a period of 200 days at 60 sites randomly selected. We used distances from human settlements, roads and the nearest water holes, frequency of game species and sampling effort as covariables that could influence poachers' occupancy and detectability and to identify potential poaching areas. Occupancy poachers were higher in sites with higher frequency of game species. Frequency of game species and distance from roads had a negative effect on the detectability of poachers. Spatial analysis indicated three critical poaching areas within and around the Boqueirão da Onça National Park, associated with roads and some isolated cattle and goat farms. In this study, we provided an assessment of poaching spatial patterns in relation to different landscape elements and biotic influences, indicating critical areas where enforcement efforts should be focused. Hotspots are clearly concentrated within and on the edge of National Park. The approach presented here to identify poaching hotspots is effective and economical, and therefore may be applied in other protected and non-protected areas throughout the world. Unlabelled Image • The game species abundance is a strong predictor of poacher's occupancy. • Road opening in natural areas increases poaching intensity. • Synergistic effects of roads, game species frequency, and proximity to farms create poaching hotspots [ABSTRACT FROM AUTHOR]

Road verges provide habitats that have considerable potential as a tool for pollinator conservation, especially given the significant area of land that they collectively cover. Growing societal interest in managing road verges for pollinators suggests an immediate need for evidence-based management guidance. We used a formal, global literature review to assess evidence for the benefits of road verges for pollinators (as habitats and corridors), the potential negative impacts of roads on pollinators (vehicle-pollinator collisions, pollution, barriers to movement) and how to enhance road verges for pollinators through management. We identified, reviewed and synthesised 140 relevant studies. Overall, the literature review demonstrated that: (i) road verges are often hotspots of flowers and pollinators (well established), (ii) traffic and road pollution can cause mortality and other negative impacts on pollinators (well established), but available evidence suggests that the benefits of road verges to pollinators far outweigh the costs (established but incomplete), and (iii) road verges can be enhanced for pollinators through strategic management (well established). Future research should address the lack of holistic and large-scale understanding of the net effects of road verges on pollinators. We provide management recommendations for enhancing both individual road verges for pollinators (e.g. optimised mowing regimes) and entire road networks (e.g. prioritising enhancement of verges with the greatest capacity to benefit pollinators), and highlight three of the most strongly supported recommendations: (i) creating high quality habitats on new and existing road verges, (ii) reducing mowing frequency to 0–2 cuts/year and (iii) reducing impacts of street lighting. Unlabelled Image • Road verges have considerable potential to be used for pollinator conservation. • Verges can be hotspots of flowers and pollinators in managed landscapes. • Traffic and road pollution can cause mortality and other impacts on pollinators. • Evidence suggests the benefits of road verges to pollinators outweigh the costs. • Road verges can be enhanced for pollinators through strategic management. [ABSTRACT FROM AUTHOR]