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The article discusses wildlife-vehicle collisions in North America with a focus on the increased construction of roads and the design of wildlife crossings within the context of a design competition for a wildlife crossing over Interstate 70 in Vail Pass, Colorado won by HNTB with Michael Van Valkenburgh & Associates.

The Earth’s network of roads is vast and is reaching new regions with each year that passes. The effects of roads as barriers to animal movement and as conduits for other threats to the conservation of natural systems are well documented. Wildlife crossings can successfully mitigate some of the negative effects of roads by making it possible for wildlife to traverse even major highways safely. However, despite decades of successful deployment, the use of crossings remains uncommon. Their continuing rarity has a variety of origins, but cost and public appreciation of their benefits remain the most important limiting factors. We hypothesize that design can address both challenges. Here we describe a crossing design that is unconventional by current standards. We employ massed wood in a bridge crossing using laminated modules. These modules make it straightforward to customize the structure to its site while also keeping costs low, both because the materials are relatively inexpensive and because the need for specialized labor has been minimized. Other benefits include the rapidity with which the structure can be raised and the reduced need to close roadways during construction. Collectively, these innovations are intended to make crossings much less expensive and more easily adapted to a particular application. The use of massed wood creates a structure that is strong enough to support landscaping on its surface, is both weather- and fire-resistant, and that sequesters many tons of carbon in a long lasting structure. [ABSTRACT FROM AUTHOR]

Ecologists, landscape architects, and bridge and structural engineers do not work together often enough, and this paper illustrates the advantages of collaboration in the design of the next generation wildlife crossing. The process and details of collaboration are as unique as the solutions included in the award winning entry for the ARC International Wildlife Crossing Infrastructure Design Competition. This article illustrates the benefits of multidisciplinary collaboration, how ecological restoration was foundational to the design, and how all parties worked to develop a new and innovative highway crossing for wildlife. [ABSTRACT FROM AUTHOR]

In landscapes inundated with roads, wildlife is likely to negatively interact with vehicles during its lifetime. Wildlife crossing signs are easily deployed, cost-effective, and meant to encourage wildlife-friendly driving practices in hopes of reducing wildlife-vehicle collisions (WVCs) along roads. Here we use the placement of turtle crossing signs as a case study to provide recommendations for informed placement of mitigation structures across regional landscapes in Ontario and elsewhere. We collected relevant information (design, theft, and location) from 369 turtle crossing signs placed along roads. We then compiled turtle-vehicle collision data from various sources to statistically analyze where they occur in relation to habitat and road type. We also compared the locations of turtle crossing signs to validated hotspots, which was equivalent to 19,000 km of road in Southern Ontario. We found that at least 27% of signs were stolen and at least 10 different design types exist for crossing signs in Ontario. Thirteen percent of signs were not located at validated hotspots, and turtle-vehicle collisions occurred most often on paved highways and county roads. We conclude that a road mitigation strategy should accurately inventory where structures are located and monitor their effectiveness. Structures should be selectively placed using the best available information, such as metapopulation science and WVC data, especially in regions heavily fragmented by roads. In multi-jurisdictional regions, an effective strategy should also consider regional coordination that focuses on standardized sign design and information sharing in an adaptive approach. [ABSTRACT FROM AUTHOR]

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

The paper characterizes the problem of preservation of wildlife animals in connection with extension of transportation road systems. The constantly evolving transportation infrastructure in Europe, especially in its Midwestern part, on one hand connects, making it easier for people to travel and ship goods, but on the other hand it irreversibly divides and leaves a painful impress on virgin natural areas (fragmentation of the environment). The paper briefly presents the European Ecological Network Nature 2000 as the European Union program concerning the environmental protection. It enumerates possible types of animal crossings together with their characteristics. Some examples of underpasses, overpasses and crossings on the road surface are also presented. It also presents specificity and phases of designing engineering structures of this type, as well as the most common design errors and their influence over the use of such structures by animals. Finally the soil-steel bridge structures made from corrugated plates are characterized in their function as crossings for animals. The conclusion mentions complexity of the problem of animal crossing construction, which can be of use to designers and constructors of this type of engineering structures. [ABSTRACT FROM AUTHOR]

Roads generate a variety of influences on wildlife populations; however, little is known about the effects of roads on endemic wildlife on islands. Specifically, road-kills of island foxes ( Urocyon littoralis) on San Clemente Island (SCI), Channel Islands, California, USA are a concern for resource managers. To determine the effects of roads on island foxes, we radiocollared foxes using a 3-tiered sampling design to represent the entire population in the study area, a sub-population near roads, and a sub-population away from roads on SCI. We examined annual survival rates using nest-survival models, causes of mortalities, and movements for each sample. We found the population had high annual survival (0.90), although survival declined with use of road habitat, particularly for intermediate-aged foxes. Foxes living near roads suffered lower annual survival (0.76), resulting from high frequencies of road-kills (7 of 11 mortalities). Foxes living away from roads had the highest annual survival (0.97). Road-kill was the most prominent cause of mortality detected on SCI, which we estimated as killing 3-8% of the population in the study area annually. Based on movements, we were unable to detect any responses by foxes that minimized their risks from roads. The probabilities of road-kills increased with use of the road habitat, volume of traffic, and decreasing road sinuosity. We recommend that managers should attempt to reduce road-kills by deterring or excluding foxes from entering roads, and attempting to modify behaviors of motorists to be vigilant for foxes. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

ABSTRACT Recent studies on the impacts of forest fragmentation on understory insectivorous birds in the Neotropics have highlighted that even narrow linear clearings, such as roads, can affect the movements of this guild of birds. We used playback trials of territorial vocalizations to assess the movements of three understory insectivorous bird species across two unpaved roads bisecting Parque Estadual Carlos Botelho in southeast Brazil, located within one of the largest remaining continuous Atlantic Forests. Movement patterns varied among species. While Chamaeza campanisona never crossed these roads, Pyriglena leucoptera crossed them in almost 100 percent of tests. Although Conopophaga lineata exhibited a significantly lower number of crossings along cleared sites, it was eventually willing to traverse the roads, showing an intermediate pattern. Shaded areas with connected canopy did not improve birds' willingness to cross roads compared with areas where treecrowns were at least 3 m apart. Similarly, birds' willingness to cross an 8-m wide road with limited traffic (six vehicles/wk) was not significantly greater than that of a 12-m wide road with more intense traffic (41 vehicles/d). Our findings suggest that the negative impact of roads on bird movement is an issue that should be addressed by managers of Atlantic Forest conservation units, especially as economic development results in pressure to pave and widen roads. Abstract in Portuguese is available at . [ABSTRACT FROM AUTHOR]

Abstract: Roads and associated human development are prevalent features in many landscapes and can have significant impacts on wildlife populations, including the creation of barriers to movement that can reduce connectivity within and among populations. We evaluated how a highway in the northern Rocky Mountains influenced movements of American black bears (Ursus americanus) in a landscape modified by humans, resulting from human residences, recreation, and resource extraction. The objectives of the study were to determine habitat characteristics that were selected at locations where bears crossed the highway and develop and evaluate a predictive model for road-crossing locations based on habitat characteristics. Eleven out of 23 black bears fitted with GPS collars crossed highway 95 at least once. When bears crossed the highway they selected for specific habitat attributes, at both roadside and landscape scales, characterized by forested areas away from human development, with additional important habitat features including distance to cover, amount of shrub along the highway, and distance to water. Validation of our model with 24 independent highway crossing events from 2 years demonstrated high model predictability. We described how animal movement data can be used to identify and predict important road crossing areas for wildlife, which can assist in designing planning strategies for roadways and landscapes to facilitate wildlife movement to maintain connectivity among populations and to reduce wildlife–vehicle collisions. [Copyright &y& Elsevier]

The negative effects of roads on wildlife in tropical rainforests are poorly understood. Road construction has high priority in Africa, while negative impacts of roads on wildlife movement often are neglected. This study aims at providing information on the effects of roads on crossing behaviour of rainforest wildlife. The probability that wildlife would cross forest roads was analysed for association with ten different factors that were linked to road presence or construction. Factors were divided into three classes: vegetation cover, topography and human influence. A trackplot survey was done in southern Cameroon, Africa. Trackplots were laid along a 32 km unpaved logging road that intersects Campo-Ma’an National Park. Tracks of several species were found frequently (e.g. genets and porcupines); while others were found only sporadically (e.g. forest duikers and apes). The actual physical obstacles found along the road (e.g. logs, banks, etc.) were highly negatively correlated with crossing probabilities. For all wildlife species high vegetation cover was positively correlated to crossing probability. This study indicates that roads have a large impact on wildlife, and suggests which factors could be altered during road construction and maintenance in order to mitigate these impacts. [ABSTRACT FROM AUTHOR]

Intuitively, wildlife crossing structures should enhance the viability of wildlife populations. Previous research has demonstrated that a broad range of species will use crossing structures, however, questions remain as to whether these measures actually provide benefits to populations. To assess this, studies will need to determine the number of individuals using crossings, their sex, and their genetic relationships. Obtaining empirical data demonstrating population-level benefits for some species can be problematic and challenging at best. Molecular techniques now make it possible to identify species, individuals, their sex, and their genetic relatedness from hair samples collected through non-invasive genetic sampling (NGS). We describe efforts to pilot a method to assess potential population-level benefits of wildlife crossing structures. We tested the feasibility of a prototype NGS system designed to sample hair from black bears (Ursus americanus) and grizzly bears (U. arctos) at two wildlife underpasses. The piloted hair-sampling method did not deter animal use of the trial underpasses and was effective at sampling hair from more than 90% of the bear crossing events at the underpasses. Hair samples were also obtained from non-target carnivore species, including three out of five (60%) cougar (Puma concolor) crossing events. Individual identification analysis revealed that three female and two male grizzly bears used one wildlife underpass, whereas two female and three male black bears were identified as using the other underpass. Of the 36 hair samples from bears analyzed, five failed, resulting in an 87% extraction success rate, and six more were only identified to species. Overall, 70% of the hair samples from bears collected in the field had sufficient DNA for extraction purposes. Preliminary data from our NGS suggest the technique can be a reliable method to assess the population-level benefits of Banff wildlife crossings. Furthermore, NGS can be an important tool for the conservation value of wildlife crossings for other taxa, and we urge others to carry out evaluations of this emerging methodology. [ABSTRACT FROM AUTHOR]

Surveys show relatively little support for use restrictions to protect wilderness experiences. However, such conclusions based on aggregate data could hide important differences among visitors. Visitors with more wilderness-dependent trip motives were hypothesized to be more supportive of use restrictions. Using survey data from visitors to 13 wildernesses, cluster analysis of motivations and wilderness involvement generated three clusters that differed in sensitivity to social conditions and support for use restrictions. The group with motives most aligned with the Wilderness Act was slightly more adversely affected by social conditions and more supportive of regulations. However, none of the groups supported use restrictions to protect opportunities for solitude. [ABSTRACT FROM AUTHOR]

Abstract: Bay scallop culture has become a major sector in marine culture industry in China since its first introduction in early 1980s. However, despite various efforts including several re-introductions, decreases in major production traits such as survival and growth rates are still a major concern to the industry. This study aimed to evaluate the performance of offspring derived from mass spawning type crossbreeding between different populations in bay scallops. The results showed that significant differences in growth and survival existed among the four intra-population crosses at larval stages, but not at the adult stage. Increases in growth and survival rates were observed in most inter-population crosses at larval stages and in all inter-population crosses at the adult stage. The survival rate of the best inter-population crosses was 156.7% higher than the average survival rate of all the intra-population crosses. Through mass spawning type crossbreeding between different populations, we were able to produce offspring with improved production traits and the results may have immediate application in bay scallop culture. [Copyright &y& Elsevier]

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

The establishment of protected areas is seen as one solution to preserve remaining components of natural ecosystems. However, the preservation role of protected areas may conflict with human activities such as industrial development and tourism. Canada's Banff National Park (BNP) hosts about 3 million visitors per year, has approximately 8000 full-time residents, and is bisected by nationally significant rail and road transportation routes. The upgrading of the Trans-Canada Highway (TCH) from two to four lanes within BNP has highlighted the park's conflicting roles. The TCH in BNP has been subject to pioneering efforts to reduce its negative effects on wildlife mortality and movement. Over 12 years of monitoring, BNP's highway mitigation measures have made this stretch of road one of the most intensely studied in the world. Both adaptive management and flexible institutional arrangements made this effort possible. The results of monitoring studies are being shared with a broad audience, from transportation practitioners and ecologists to the general public and school children. By learning more about the success of highway mitigation, a community of informed citizens is taking shape and becoming active in their understanding of nature and science. [ABSTRACT FROM AUTHOR]

Abstract: Multiple factors determine the use and effectiveness of wildlife passages and crossings installed in new roads as mitigation measures against the barrier effect. It is unknown whether factors such as seasonality determine the use of these structures. This analyses the seasonality of structure used by vertebrates. Forty-eight transverse structures crossing the A-52 motorway in north-western Spain are studied during the summer and winter of 2002–03. The use of structures by terrestrial vertebrates was monitored by tracks left in marble dust and photographic systems, and comparisons carried out by means of generalized lineal methods for count data. Structural factors mostly determined the differential use of passage types by species but seasonal changes were detected both in the intensity of use and in passage selection by some species. [Copyright &y& Elsevier]

Globally, human activities impact from one-third to one-half of the earth’s land surface; a major component of development involves the construction of roads. In the US and Europe, road networks fragment normal animal movement patterns, reduce landscape permeability, and increase wildlife-vehicle collisions, often with serious wildlife population and human health consequences. Critically, the placement of wildlife crossing structures to restore landscape connectivity and reduce the number of wildlife-vehicle collisions has been a hit-or-miss proposition with little ecological underpinning, however recent important developments in allometric scaling laws can be used to guide their placement. In this paper, we used cluster analysis to develop domains of scale for mammalian species groups having similar vagility and developed metrics that reflect realistic species movement dynamics. We identified six home range area domains; three quarters of 102 species clustered in the three smallest domains. We used HR0.5 to represent a daily movement metric; when individual species movements were plotted against road mile markers, 71.2% of 72 species found in North America were included at distances of ⩽1mi. The placement of wildlife crossings based on the HR0.5 metric, along with appropriate auxiliary mitigation, will re-establish landscape permeability by facilitating wildlife movement across the roaded landscape and significantly improve road safety by reducing wildlife vehicle collisions. [Copyright &y& Elsevier]

A major target for environmental managers when trying to minimise the road-barrier effect on wildlife is to improve permeability to animal movements. Previous studies have demonstrated that drainage culverts are used by vertebrates, although knowledge of the main influencing factors remains limited. The use of 34 culverts from two roads in southern Portugal, differing in traffic volume, vehicle speeds and configuration, was evaluated by the analysis of terrestrial vertebrate footprint data (408 passage-operative days). Culvert crossings were related to various explanatory variables by means of canonical ordination techniques. We recorded 901 complete crossings, corresponding to an average of 2.2 crossings/culvert/operative day. Thirteen taxa were detected, all in more than one passage. Animal species included reptiles, small mammals, lagomorphs, carnivores and domestic dogs and cats. Our results suggest that fencing might have a funnelling effect, directing larger animals toward culverts. Also, vegetation covering culvert entrances seems to have a positive effect, particularly on genets; longer passages with entrances far from the pavement were, apparently, avoided by smaller animals; a lower number of crossings was detected on passages with detritus pits; the closest passages to urban areas are more often used by domestic species; forest-living species favour passages with low, open land cover nearby; and smaller species, like lagomorphs and small mammals, appear to use more culverts near the pavement, which probably reflects the importance of road verges as refuges for these species. Although not used by all species present in the study area, constructing numerous passages of different sizes without detritus pits and which are distributed along roads might be an important step in mitigating road fragmentation effects on animal populations. [ABSTRACT FROM AUTHOR]

Wildlife crossing structures are intended to increase permeability and habitat connectivity across roads. Few studies, however, have assessed the effectiveness of these mitigation measures in a multispecies or community level context. We used a null model to test whether wildlife crossing structures serve large mammal species equally or whether such structures limit habitat connectivity across roads in species-specific ways. We also modeled species responses to 14 variables related to underpass structure, landscape features, and human activity. Species performance ratios (observed crossing frequency to expected crossing frequency) were evaluated for four large carnivore and three ungulate species in 11 underpass structures in Banff National Park, Alberta, Canada. Observed crossing frequencies were collected in 35 months of underpass monitoring. Expected frequencies were developed from three independent models: radio telemetry, pellet counts, and habitat-suitability indices. The null model showed that species responded to underpasses differently. In the presence of human activity carnivores were less likely to use underpasses than were ungulates. Apart from human activity, carnivore performance ratios were better correlated to landscape variables, and ungulate performance ratios were better correlated to structural variables. We suggest that future underpasses designed around topography, habitat quality, and location will be minimally successful if human activity is not managed. [ABSTRACT FROM AUTHOR]

Although roads are important cultural objects in our society, they can have negative impacts on the environment. Bat populations are affected by roads in several ways, including habitat loss, death due to collision with vehicles, and reduced habitat connectivity. In recent years, different mitigation practices have been introduced to help animals safely cross roads, reduce road kills, and minimize habitat fragmentation. This study aims to investigate to what extent two types of existing wildlife crossings (a green bridge and an underpass) on the A21 highway (in Northern Germany) are used by bats. All-night acoustic recordings of bat activity at the wildlife crossings, on the highway, and in the surroundings show that bats use both mitigation structures. Our results indicate that bats use mitigation structures depending on their degree of clutter-adaptation: Species from the genus Myotis , which are highly clutter-adapted, were the most recorded in the underpass, while Pipistrellus spp., which are less clutter-adapted, were the most recorded on the Green Bridge. Contrary to expectations, many bat passes were registered on the highway as well. Long-term monitoring studies are needed (including counting of bat fatalities) to clarify if further mitigation measures are needed. In conclusion, the use of wildlife crossings as mitigation structures can be effective, mostly for clutter-adapted species (Myotis spp. and Plecotus auritus). • The presence of mitigation structures (safe crossing points) can increase habitat connectivity. • Bats used the two mitigation structures differently depending on the species and their degree of clutter-adaptation. • The presence of wildlife crossing structures can minimize road risks in the long term, especially for clutter-adapted species. [ABSTRACT FROM AUTHOR]

The ecosystem fragmentation due to transportation infrastructure causes a road-kill phenomenon. When making policies for mitigating road-kill it is important to select target-species in order to enhance its efficiency. However, many wildlife crossing structures have been questioned regarding their effectiveness due to lack of considerations such as target-species selection, site selection, management, etc. The purpose of this study is to analyse the impact of habitat patches on wildlife road-kill and to suggest that spatial location of habitat patches should be considered as one of the important factors when making policies for mitigating road-kill. Habitat patches were presumed from habitat variables and a suitability index on target-species that was chosen by literature review. The road-kill hotspot was calculated using Getis-Ord Gi*. After that, we performed a correlation analysis between Gi Zscore and the distance from habitat patches to the roads. As a result, there is a low negative correlation between two variables and it increases the Gi Z-score if the habitat patches and the roads become closer. [ABSTRACT FROM AUTHOR]