There are more than 1,400 species of bats worldwide and they play critically important roles in ecosystem health. We conducted an international systematic review and found that many species of bats are significantly impacted by barrier effects due to the presence of roads, by mortality due to collision with vehicles, and by habitat loss and decreased activity due to habitat alteration.

Hedgehogs are among the most common victims of roadkill across Europe and most European hedgehog species are in decline. We undertook a comprehensive literature review to identify the impacts of road mortality on the viability of European hedgehog populations, potential mitigation solutions, and remaining knowledge gaps.

Ponds in Hungary located in the road-effect zone – the area within 1 km of a highway – had a lower abundance of larval amphibians (tadpoles and newt larvae). There were also fewer amphibian larvae in ponds that were surrounded by a high percentage of roads, while there were more larvae of some species in ponds surrounded by large areas of connected wetland and terrestrial habitat.

Route 34: Section Hacienda Barú Refuge is the first site in Costa Rica to have underpasses specifically for wildlife. After monitoring these structures, 21 vertebrate species have been recorded using them, preferring square, big underpasses with a natural substrate and vegetation cover.

We studied the trade-off between wildlife mortality on roads and the barrier effect of fences. We found that fences are more likely to be beneficial for wildlife populations the higher the inclination of the species to attempt to move across the road and the higher the probability of the species being killed on the road.

On the megadiversity island of Sumatra, Indonesia, a mining corporation has gained government approval to construct a major, 88-kilometer-long road that would cut across the Harapan Rainforest, one of the last surviving tracts of lowland rainforest on the island. We use strategic land-use-planning methods to identify alternate routes for the road that have far lower environmental and economic costs than the road being currently planned.

We used custom-built cameras and image recognition software to evaluate the use and effectiveness of a tunnel and fence system for amphibians at a road mitigation site in England. Over four years, we found high rates of use of the tunnels, no roadkill, colonisation of newly-built ponds and a substantial increase in the population size of several species, including the nationally protected Great Crested Newt.

This study aimed to clarify the level of agreement between potential movement corridors and areas of high predicted road mortality in order to identify optimal locations for mitigation. We recommend considering both approaches in parallel.

Bird collisions with overhead powerlines is one of the most significant human causes of bird mortality worldwide, with estimates in the millions of birds killed annually and contributing to the decline of many species. We undertook a comprehensive literature review and identified the factors that increased bird collision risk with power lines, the existing mitigation measures, and remaining knowledge gaps.

A republished article from The Conversation. An analysis of the ecological effects of fencing on ecosystems around the world.

Lighting in wildlife underpasses significantly reduces their use by bats. Bats are more likely to cross the road rather than use the underpasses when they are lit, greatly increasing their risk of mortality.

Water culverts along Autoroute 10 in Quebec are used considerably less than one would expect for designated wildlife passages for mammals, since out of 20 species present in the vicinity of the culverts, only about half of them were ever detected making a full crossing, and only two species highly tolerant to water crossed the structures on a regular basis (common raccoons and American mink). Water level and use of polyethylene as construction material were the strongest deterrents.

The extensive loss of semi-natural grassland habitats has led to a dramatic decline of plant and insect species that live in these habitats, but in landscapes with power line corridors the loss of plant species seems to be slower. Currently, neither road verges nor power line corridors are intentionally managed to enhance biodiversity, which makes them an invaluable resource for conservation if we were to manage their extensive area for this purpose.

In order to reduce wildlife-vehicle collisions, is it better to use a few long, or many short, fences (FLOMS)? We devised an adaptive plan for prioritizing road sections for fencing, based on roadkill hotspots and coldspots, considering multiple scales and the FLOMS trade-off.

Many populations of amphibians are declining rapidly across Asia and road kill is a significant cause. In this project, we designed and tested a range of culverts to identify amphibian-friendly options to mitigate roadkill and barrier effects of roads.

Bird mortality through collision and electrocution are probably the most well-known ecological impacts of overhead power lines. However, our systematic review identified at least 26 other potential impacts on biodiversity that should be considered during ecological impact assessments. We developed a logical framework to help practitioners systematically identify and assess the potential ecological impacts of powerlines.

To reduce wildlife mortality from train collisions, we invented a warning system that emits flashing lights and bell sounds prior to the arrival of a train. A test of this system showed that animals fled earlier from trains in the presence of warning signals.

This study in Mexico showed that small wildlife experienced high rates of mortality and just like large charismatic species, they also require and deserve actions to avoid extinction.

Jaguars together with other neotropical species only used purpose-built wildlife underpasses under a highway in Mexico, even when ‘large enough’ drainage structures were available. Drainage structures may work as crossings for some species but can’t substitute proper wildlife underpasses.

Great Britain has seen traffic levels increase while bird species are declining but there is limited understanding about this link. This study assessed the spatial associations between roads and birds across Britain.