Road Ecology: Landscapes for wildlife

More than 275,000 kilometres of roads span Ontario, and the network is in a perpetual state of expansion. Southern Ontario has tremendous biodiversity and the greatest Species at Risk (SAR) richness in the province. The potential for conflicts between vehicles and wildlife seems inevitable—until you consider road ecology, the study of the interaction between roads and the environment. Implementing road ecology practices in transportation planning helps build safe and cost-efficient roads that function in harmony with the local environment. Improving the way wildlife/road interactions are managed in Ontario has been championed by the Ontario Road Ecology Group (OREG), a not-for-profit organization that protects biodiversity from the threats of roads by facilitating partnerships among government and non-government agencies dedicated to resolving road ecology issues through research, policy, and stewardship.

As a prominent anthropogenic feature on the landscape, transportation networks are a formidable threat to wildlife. The main threats include: 1) habitat loss, fragmentation, and degradation; 2) direct mortality; 3) inaccessibility to critical resources; and 4) sub-division of populations, which renders populations more susceptible to local extinction or extirpation. Roads also create perilous habitat that attracts wildlife to nest, feed, or bask, and where there are roads, there is increased access to habitats for poaching, dumping, and other illegal activities.

Mitigation measures that keep wildlife safe from roads, such as fencing and dedicated wildlife tunnels and bridges, are critical infrastructure components that help realize habitat connectivity objectives. Criteria to identify priority mitigation sites include, but are not limited to, areas of concentrated wildlife/road mortality and/or suitable wildlife corridor habitat. Additionally, road planning and design details such as selecting a route alignment that minimizes the negative effects on the local natural landscape, designing lighting systems that reduce ambient light emission, and adding curb and median structures that render the road more permeable for wildlife movement will also influence how roads interact with the environment. Routine road maintenance work such as vegetation management practices (e.g., mowing) may also have deleterious effects on wildlife and may be easily modified to reduce the risk of the activity (e.g., raise mower blades and schedule mowing to avoid key movement periods). Mitigation is best approached as a comprehensive strategy that also incorporates habitat creation (such as nesting beaches for turtles), public engagement, and policy. Ontario has developed policies that direct municipalities to identify, conserve, and link natural heritage features for the movement of native plants and animals across the landscape to ensure the long-term protection of biodiversity.

Municipalities across Ontario are becoming more aware of the need for habitat connectivity and the responsibility planners and designers have to consider and contribute to achieving a more permeable landscape for wildlife movement. Using conventional planning tools and applying a road ecology lens allows planners to examine the landscape from a wildlife movement perspective, identify where roads(existing or planned) are a threat to wildlife, and apply solutions.

In Brampton, Ontario, Heart Lake Road has evolved from a quiet backroad to a busy commuter road. Increasing traffic volumes are the norm as communities develop housing and employment lands. Segments of Heart Lake Road bisect Provincially Significant Wetland habitat where thousands of animals cross and get killed. To address the issue, the Toronto and Region Conservation Authority, City of Brampton, OREG, and the local community collaborated to initiate a citizen science program that culminated in motivating the municipality to install a dedicated wildlife passage complete with fencing to keep animals off the road and direct them to the culvert. The passage system was complemented by wildlife crossing signs to raise public awareness and habitat creation to augment the mitigation strategy to offer safe, alternative habitat away from the road to serve the local turtle population. The municipality continues to integrate road ecology principles and practices into their standard operations to build a community that is compatible for both people and wildlife.

Road ecology principles offer landscape architects a unique toolkit that facilitates the coordinated management of natural and built environments. Connectivity conservation is essential to reduce habitat fragmentation, sustain resilient ecosystems, and enable wildlife migrations. As species’ home ranges shift in response to climate change, planning practices can help convey wildlife through the landscape. Even within settlement areas, planners may evaluate different land uses for their capacity to move wildlife and maintain, enhance, restore, and protect these linkages and corridors in the community.

The migration of a Blanding’s Turtle (Ontario status: Threatened) among urban habitat types as they fulfill their life cycle, is just as monumental and inherent to our cultural identity as the migration of Caribou (Ontario status: Threatened) across Ontario’s expansive boreal forest.

Landscape architects have an invaluable role to play in promoting and instilling road ecology concepts into routine site analyses as well as design plans and implementation. With a unique skill set, landscape architects are able to meet the task of rendering the landscape more permeable to wildlife by designing discrete infrastructure that blends into the environment or by envisioning iconic structures, such as the Ministry of Transportation of Ontario’s wildlife overpass on Highway 69. There are a myriad of opportunities to advance the way society views and influences the relationship between roads and wildlife. Road ecology is a multi-faceted and growing field that ensures a safe landscape in which we can all thrive.

TEXT BY MANDY KARCH, EXECUTIVE DIRECTOR OF THE ONTARIO ROAD ECOLOGY GROUP.