Roads may threaten the persistence of wildlife populations by acting as barriers to movement and/or sources of increased mortality across the landscape. Amphibians and reptiles have been identified as being particularly susceptible to negative road impacts. Many species migrate annually among habitats to support basic life history requirements such as breeding, development, foraging, and overwintering. For these species, individuals may need to successfully cross roads multiple times each year for the population to persist. Many are slow-moving and freeze in the presence of danger, making it almost impossible for them to avoid oncoming vehicles. Although there are a plethora of road mortality location and count data, the effects of road mortality on the long-term viability of amphibian and reptile populations and metapopulations are mostly unknown due to a lack of information on their abundance, vital rates, behavior, and spatial and temporal dynamics.
Conservation of these populations and species will require planning for habitat connectivity by designing, installing, and maintaining safe and effective crossing structures that are informed by the ecology and biology of amphibians and reptiles. Currently, when a crossing is built and animals are documented using the crossing, it is common for everyone to think “problem solved”! But what is the effect of the crossing structure and barrier fencing on the population? Are more or less animals successfully crossing the road? How does this effect the long-term viability of the population? In addition, passage use may increase or decrease over time but long-term studies are very rare.
We need the science to make informed decisions in how to mitigate road mortality and maintain connectivity, where needed, for impacted populations. There is a need for continued research and monitoring of the effectiveness of passages of different sizes, lengths, internal structures, light, sound, and moisture levels as well as innovations in designs and materials to make crossings best simulate natural conditions. Part of the problem has been the cost and effort to actively monitor amphibians and reptiles. However, breakthroughs in passive monitoring methods, such as increased sensitivity and quality of motion-sensitive cameras, use of active trigger cameras, different wavelengths to enhance detection of target species, and machine learning to process photos will continue to make it easier and more cost-effective to conduct these field studies.
We welcome research studies, analyses, and reviews that address these topics and help to increase our understanding of both the effects of roads on amphibian and reptile populations and the effectiveness of mitigation structures. Papers should do more than quantify road mortality or use of passage(s) but advance our understanding of road ecology for reptiles and amphibians (frogs, toads, salamanders, snakes, lizards, turtles, and/or tortoises). We are particularly interested in the following topics:
• Literature reviews and meta-analyses: Road impacts, Effectiveness of Mitigation
• Population viability analyses that integrate road mortality and/or effects of mitigation structures on vital rates
• Movement models: Effects of roads, barriers, or crossing structures on species movement
• Effectiveness of crossing structures for single or multiple species
• Assessment of the effectiveness of crossing structures based on technical attributes (e.g., size, length, materials, placement, spacing).
• New methodologies and tools for research & monitoring
• Innovations in the design of crossing structures and barrier systems that improve existing technologies
• Roads or road verges as corridors for dispersal or population expansion
• Effects of road characteristics and traffic volume on road mortality and road avoidance
• Spatial methods for habitat connectivity that inform roadkill mitigation priorities
• Cumulative impact analyses that include roads as a population stressor.
Roads may threaten the persistence of wildlife populations by acting as barriers to movement and/or sources of increased mortality across the landscape. Amphibians and reptiles have been identified as being particularly susceptible to negative road impacts. Many species migrate annually among habitats to support basic life history requirements such as breeding, development, foraging, and overwintering. For these species, individuals may need to successfully cross roads multiple times each year for the population to persist. Many are slow-moving and freeze in the presence of danger, making it almost impossible for them to avoid oncoming vehicles. Although there are a plethora of road mortality location and count data, the effects of road mortality on the long-term viability of amphibian and reptile populations and metapopulations are mostly unknown due to a lack of information on their abundance, vital rates, behavior, and spatial and temporal dynamics.
Conservation of these populations and species will require planning for habitat connectivity by designing, installing, and maintaining safe and effective crossing structures that are informed by the ecology and biology of amphibians and reptiles. Currently, when a crossing is built and animals are documented using the crossing, it is common for everyone to think “problem solved”! But what is the effect of the crossing structure and barrier fencing on the population? Are more or less animals successfully crossing the road? How does this effect the long-term viability of the population? In addition, passage use may increase or decrease over time but long-term studies are very rare.
We need the science to make informed decisions in how to mitigate road mortality and maintain connectivity, where needed, for impacted populations. There is a need for continued research and monitoring of the effectiveness of passages of different sizes, lengths, internal structures, light, sound, and moisture levels as well as innovations in designs and materials to make crossings best simulate natural conditions. Part of the problem has been the cost and effort to actively monitor amphibians and reptiles. However, breakthroughs in passive monitoring methods, such as increased sensitivity and quality of motion-sensitive cameras, use of active trigger cameras, different wavelengths to enhance detection of target species, and machine learning to process photos will continue to make it easier and more cost-effective to conduct these field studies.
We welcome research studies, analyses, and reviews that address these topics and help to increase our understanding of both the effects of roads on amphibian and reptile populations and the effectiveness of mitigation structures. Papers should do more than quantify road mortality or use of passage(s) but advance our understanding of road ecology for reptiles and amphibians (frogs, toads, salamanders, snakes, lizards, turtles, and/or tortoises). We are particularly interested in the following topics:
• Literature reviews and meta-analyses: Road impacts, Effectiveness of Mitigation
• Population viability analyses that integrate road mortality and/or effects of mitigation structures on vital rates
• Movement models: Effects of roads, barriers, or crossing structures on species movement
• Effectiveness of crossing structures for single or multiple species
• Assessment of the effectiveness of crossing structures based on technical attributes (e.g., size, length, materials, placement, spacing).
• New methodologies and tools for research & monitoring
• Innovations in the design of crossing structures and barrier systems that improve existing technologies
• Roads or road verges as corridors for dispersal or population expansion
• Effects of road characteristics and traffic volume on road mortality and road avoidance
• Spatial methods for habitat connectivity that inform roadkill mitigation priorities
• Cumulative impact analyses that include roads as a population stressor.