Biopasses

• Design Considerations for Wildlife Crossings talks about building a biopass from an engineering perspective. It offers a graph showing the percentage of benefits from different types of intervention to help indicate which are the most or least cost effective, as well as helping to prepare for the legally required steps and costs of implementation before beginning a project.

• Conserving Wildlife On and Around Maine’s Roads "This brochure outlines how Maine’s local planning boards, comprehensive planning committees, local public works departments, regional transportation planning groups, and state transportation agencies can use these strategies to improve and maintain Maine’s wildlife habitats."

• Practical Guidelines Ecology in Practice: Improving Infrastructure Habitats Along Roads (PDF) "This document contains guidelines on how ecological principles can be fully incorporated in the different phases from planning, to preparation and decision to implementation. These aspects are addressed with a landscape, ecotone, and habitat perspective. The document contains a general introduction on roadside challenges and concepts, the ecological principles underpinning the approach, and guidelines from a landscape perspective, to edge and ecotone effects, to roadside habitat quality. The specific guidelines are based on comprehensive reviews of the scientific and grey literature in the project Ecology in practice: Improving infrastructure habitats along roads (EPICroads). With a European perspective, the guidelines target an audience of strategic and operational planners at road authorities."

• Wildlife Crossing Structure Handbook Design & Evaluation in North America

Canopy Crossings & Canopy Rope Bridges

These structures can help primates, sloths, and other species safely avoid human contact or deadly vehicle accidents when roadways bisect their habitats. Some tree-dwelling species such as koalas were not found to actually use the bridges, so it is important to ensure the design will be used by the target species, appealing to the target species, and if so also safe for frequent use by that species as well as others. 

• Targeted Field Testing of Wildlife Road-Crossing Structures: Koalas and Canopy Rope-Bridges (PDF) "The suitability of structures installed to enable safe passage of wildlife across a road is most frequently determined by monitoring of structures after new roads are built. Rarely are new structures field tested before installation. We installed canopy rope-bridges in an area frequented by koalas (Phascolarctos cinereus) with the explicit aim of determining whether koalas might use such structures. Rope-bridges were of four different designs to maximise the likelihood that one might be used, as a precursor to further replication. Infrared cameras were installed on the rope-bridges as well as on two nearby reference trees to compare frequency of use. Over a monitoring period of 2.9 years no koalas were detected on the rope-bridges whereas koalas were recorded on the reference trees on 34 and 41 different 24-h periods. Rope-bridges may not be suited to an arboreal mammal that is inclined to travel along the ground to move between trees."

Dams

Dams, weirs, and other obstructions have made some migration routes totally impassable to keystone species such as salmon and eels. 

Bypass

Removal

Dams often have other negative impacts on humans, wildlife, and ecosystems, including water security issues and power shortages with the increased weather fluctuations caused by climate change. By removing man-mad obstructions, we can help repair ecosystems, and allow ancient migration patterns resume, boosting ocean life and inland ecosystems alike!

How-To Guides

• Dam Removal: A Citizen's Guide To Restoring Rivers (PDF) 

• Stream Barrier Removal Monitoring Guide (PDF) "presents detailed methods for each of the critical monitoring parameters except for macroinvertebrate and fish passage assessment. Because of the considerable variability associated with assessing these biological parameters, only general guidance is given here. The Monitoring Guide also presents important additional monitoring parameters that practitioners may choose to use on a case-by-case basis."

Call for Broad Level Classification for Dam Removals

• Session C3- A Broad Level Classification System for Dam Removals "Conceptual models of dam removal processes, backed by extensive expertise, provide a solid foundation for the deconstruction of dams. In this paper we propose a broad level classification system for dam removal projects to initiate the creation of better conceptual models for future dam removal projects. Although removing dams is not a new endeavor - people have been removing dams for almost as long as they have been building them - there is little literature on the responses of different riverine systems to dam removal. The authors of this paper have been involved in over 100 dam removal projects and have found some obvious patterns and similarities in responses between specific "categories" of dam removals. Owners, practitioners and regulators need an accurate conceptual model to help predict project outcomes at the initial stages of a project. Several current papers point to the fact that a solid conceptual model is a critical element to a successful advanced numerical model. Academics and researchers need a compiled experience base such that their research results can be more appropriately applied to a variety of projects and regions. This paper focuses on our initial endeavor to categorize dam removal efforts based on past experience in order to better predict the outcomes and potential impacts of dam removal projects, as well as start to develop conceptual models for dam removal. Key issues include, when is the removal of a dam a simple effort that could be completed quickly at minimum cost, and with little to no potential for long term impact on the river system? Which projects should include more detailed analysis and take more precautions before the dam is removed? The hundreds of dams already removed have started to unveil the answers for us. Wide impoundments with fine grained sediments respond very different than steep narrow impoundments with coarse grained sediments. Some dams have no impounded sediment stored behind them at all, while others have a century or more of accumulated sediment within the impoundment. The system response to a removal can vary greatly if the downstream channel is significantly degraded or if the sill of a dam is left in place during the removal. The results and complexity of a dam removal project can vary widely depending on these factors and others. Our classification system will help expand the discussion of whether dam removal projects fall into predictable categories, that once sorted, may help to answer many of these questions up front."

Overpass

Approach Ramps

These can help small and short-legged species access ledges and stepping stone ponds.

Ledges

These can be as simple a a piece of wood board fixed to the side of a tunnel or culvert for small species to use. Generally mice, rats, snakes, and amphibians such as toads use these.

Stepping Stone Ponds

"Not likely to use structure unless located within or adjacent to their preferred habitats, in a migratory route, or during dispersal. Amphibian habitat can be created with series of ponds in a stepping-stone pattern connecting wetland habitats separated by highway Figure 42 provides an example of this pattern on a wildlife overpass."

Vegetation

Depending on the species, vegetation can disuade some species from using a biopass, while others will not use a biopass without vegetative cover. Vegetation can offer food to hungry travelers from herbivores to pollinators.

Depending on the target species, local environment, and the stability of the overpass, plantings can include anything from native grasses and wildflowers to shrubs and trees.

Underpasses

• Effectiveness of Wildlife Underpasses and Culverts in Connecting Elephant Habitats: A Case Study of New Railway Through Kenya’s Tsavo National Parks

Culverts

"Man-made in-stream structures (e.g., culverts, dams, levees, or tide gates) can become physical barriers that impede fish passage and reduce connectivity through habitat fragmentation. Passage may also be impeded by stream diversions, water intakes, or other structures that injure fish or cause stranding. Even un-maintained fishways can impede or prevent fish access to critical habitat. Where fish passage is obstructed longitudinally within the stream, the downstream transport of habitat elements (sediment, water, wood and other material) is often obstructed as well, along with the upstream and downstream passage of many species of amphibians, reptiles, and mammals that use stream corridors for migration and as daily movement corridors." - https://people.wou.edu/~taylors/g407/restoration/WA_Dept_Forestory_2004_Fish_Passage_Techniques.pdf 

Culverts and other biopass constructions can help fish migrate, breed, and flourish. Other species including newts, frogs, and many more can also benefit from properly built, or retrofitted culverts.

• Effectiveness of Ledges In Culverts For Small Mammal Passage (PDF) "This two-year study is the first study to our knowledge that applies an experimental procedure to evaluate the utility to small mammals of ledges installed in culverts. This appears to offer a significant and inexpensive means for increasing the permeability of roadways to small mammals. This research project demonstrates that small mammals readily make use of ledges in water-filled culverts to pass under roadways."

• Effectiveness of Wildlife Underpasses and Culverts in Connecting Elephant Habitats: A Case Study of New Railway Through Kenya’s Tsavo National Parks

How to Make Wildlife-Friendly Culvers

Culverts on their own, poorly places, or made of inappropriate materials may prevent use by wildlife, harm, or even kill wildlife. That is why we have gathered resources focused on building appropriate designs, or retrofitting badly built culverts.

• Fish Friendly Culverts (PDF) Proper design, installation, and maintenance can protect both roadways and fish" Includes graphs, maps, and suggestions for sources of assistance.

• Guidelines for Culvert Construction to Accommodate Fish & Wildlife Movement and Passage (PDF) "This document is intended as a general guideline to assist in the design, planning, and placement of culverts to minimize impacts to and ensure fish and wildlife passage and movement."

• Guidelines for the Design of Fish Passage for Culverts in Nova Scotia (PDF) "The planning, design and installation of new culverts and the maintenance of existing culverts must meet requirements for fish passage under the Canadian Fisheries Act (1985). The purpose of this document is to provide procedural and technical information to ensure that engineers and other design professionals properly incorporate fish passage into watercourse crossings."

• Guidelines for the Design of Stream/Road Crossings for Passage of Aquatic Organisms in Vermont (PDF)

• Retrofitting Existing Structures for Wildlife Passage: Assessment Tools Forest Service US offers tools to help assess if retrofitting is appropriate, a process outline, photos or existing designs.

• Waterway and Wildlife Crossing Policy and Design Guide (PDF) by MaineDOT "For Aquatics Organism, Wildlife Habitat, and Hydrologic Connectivity"

Existing Wildways

or

Wildlife Corridors

North America

Western Wildway 

"In western North America, Wildlands Network envisions the world’s most extensive network of protected, connected lands: the 6,000-mile Western Wildway, also known as the Spine of the Continent. Achieving this grand vision will require coordinated conservation across international borders.

For more than 2 decades, we have been working with partner groups from the U.S., Mexico, and Canada to establish a contiguous network of private and public conservation lands along the spine of the Rocky Mountains and associated ranges, basins, plateaus, and deserts—from Mexico’s Sierra Madre Occidental to Alaska’s Brooks Range.

Protecting and connecting key core areas is crucial to rewilding the Western Wildway, where wildlife habitats have been destroyed and fragmented by centuries of human development and resource exploitation. As in the Eastern and Pacific Wildways, we’re reconnecting the Western Wildway by promoting the restoration and protection of pivotal wildlife corridors in the region.

The Western Wildway will ultimately provide wide-ranging wildlife like wolves, cougars, and other animals with room to roam, while also sustaining important ecological processes like pollination and carbon storage, and safeguarding our natural heritage for future generations.

We have worked with our partner organizations to identify the most ecologically important and vulnerable landscapes in the Western Wildway. The resulting Wildlands Network Designs (WNDs) serve as blueprints for conservation action."

"Migration is a huge feat of endurance requiring great strength and stamina. However, today birds face additional threats caused by human activity. Hungry, exhausted birds may arrive at a stopover site, only to find that it has been destroyed by farming or urbanisation. Every year, millions of birds are illegally killed by hunters, or collide with man-made structures such as powerlines. And climate change is causing habitats to shift or disappear." - https://wildlandsnetwork.org/wildways/western/ 

Oceana

Australia

Cassowary Conservation is investing in land buy backs to help create a corridor for the endangered cassowary birds

Resources

• Overview of Power Companies and Pollinators "For financial, health, and cultural reasons, serious declines in pollinator populations are causing global alarm. Many electric power companies are concerned about the decline in pollinators and would like to understand more about pollinator science, conservation opportunities, and associated costs and risks. Through management of large real estate assets, there is ecological potential to enhance pollinator habitat through well-designed, ecologically meaningful, and cost-effective actions on property that power companies manage. This technical brief provides an overview of pollinators, considerations for power companies, and an introduction to conservation strategies."

Montana

• American Prairie: Map & Guide PDF shows existing park sections, the local national park, and reservation

Wyoming

• Red Desert To Hoback Migration Assessment: Project Overview "Western Wyoming supports some of the largest and most diverse ungulate populations in North America. The performance of these herds is largely dependent on their ability to seasonally migrate from low-elevation winter ranges to high-elevation summer ranges, where they gain fat needed to survive the long Wyoming winters. Recently, the longest mule deer migration ever recorded (and 2nd longest land migration in North America) was discovered where deer travel a one-way distance of 150 miles from the low-elevation winter ranges in the Red Desert to the high mountain slopes surrounding the Hoback Basin. The deer that complete this journey spend 4 months of each year migrating and encounter a variety of natural and anthropogenic obstacles, including sand dunes, lake and river crossings, multiple highways, and more than 100 fences."

Free Software for Stream Simulation

• FishXing allows users to evaluate multiple culvert designs and effects on fish passage. fs.fed.us/biology/nsaec/fishxing  

• HY-8, V-7.0, produced by the Federal Highway Administration, is intended for hydraulic capacity design. fhwa.dot.gov/ engineering/hydraulics/software/hy8

• HEC-RAS is a river modeling program produced by the Army Corps of Engineers. It facilitates hydraulic calculations across a network of natural and constructed channels. These simulations may be conducted in either a 1-dimensional or 2-dimensional model setup. The use of a 2D model in HEC-RAS allows for increased visualization of stream velocities and flows based on various design scenarios. These models will require data gathered during the site assessment stage and the analysis of baseflow and stormflow discharges.  hec.usace.army.mil/software/hec-ras 

• River2D is a two-dimensional river modeling program created by Dr. Peter Steffler at the University of Alberta. The program lets users evaluate natural channel flow. Though the program does not directly allow for placing culverts within the model, the bed may be manipulated at the intended culvert location to allow for modeling of anticipated velocities. Most importantly, River2D uses Physical Habitat Simulation (PHABSIM) to determine usable habitat areas for specified fish species. The program contains many species habitat files; however, most are endemic to northern areas. The user may create their own species habitat files using the templates provided within the program.  

International

• The Long Run "is a membership community of nature-based tourism businesses committed to driving holistic sustainability. Our community is global and growing. Each member aspires to maintain a healthy and productive planet for posterity. Collectively, we conserve over 23 million acres of biodiversity and improve the lives of 750,000 people. We support, connect, and inspire nature-based businesses to excel in the highest sustainable standards via the tried and tested 4C framework: Conservation, Community, Culture, and Commerce (4Cs). The Long Run is a programme of Preferred by Nature."

• The Rewilding Institute "We live for the day when Gray Wolves and Grizzly Bears have connected habitat from Mexico to Alaska, when Pumas have reclaimed their homelands East and West, when salmon and other migratory fish swim freely up and down our continents’ rivers, when the oceans are teeming with whales and sharks, and when all native species regain natural patterns of abundance and distribution."

• Xerces Society for Invertebrate Conservation "is an international nonprofit organization that protects the natural world through the conservation of invertebrates and their habitats. As a science-based organization, we both conduct our own research and rely upon the most up-to-date information to guide our conservation work. Our key program areas are: pollinator conservation, endangered species conservation, and reducing pesticide use and impacts."

Botswana

• Ecoexist Project "In partnership with the community and Government we have piloted an effort to secure space for elephants by keeping essential time worn movement corridors free from future development and identify good safe farm land for people. Informed land use planning like this is essential to address a root cause of human-elephant conflict – competition for land, water and resources, and find long term solutions for coexistence. The next steps involve facilitating implementation of these plans and ensuring space is secure for both people and elephants."

South Africa

• Samara "Samara’s conservation vision is to restore one of South Africa’s most spectacular landscapes, driving ecological corridors to create the country’s third largest protected area."

 Europe

• Dam Removal Europe "Rivers have always provided fundamental and vital services for mankind and the environment. However, dams disrupt the natural functioning of rivers and can cause a wide-scale decline in fish and other river wildlife. For these reasons, it is necessary to remove these barriers to return rivers to their natural, free-flowing state."

North America

• Living Oceans: Ocean Planning "Ocean planning is an opportunity for stakeholders to put aside their conflicts and work together to find solutions to create sustainable economies, vibrant communities and healthy oceans. We need a vision to protect the natural abundance of Canada’s oceans and the coastal communities that rely on them so we can manage our use of the ocean without using it up."

• Wildlands Network are working to create Pacific, Western, and Eastern Wildways reaching from Canada to as far south as Mexico.

Maps

North America

 USA

• Agrivoltaics Map "This dynamic map represents a census of agrivoltaic installations located across the United States. The map is constantly expanding as new sites are developed. If you are aware of agrivoltaic sites that should be added to the map or have a correction..."

Funding

International

• The Rufford Foundation "Providing grant funding for nature conservation programmes and pilot projects around the world."

North America

USA

• Wildlife Crossings Funding Opportunities "The $1.2 trillion Infrastructure Investment and Jobs Act (IIJA) was signed into law on November 15, 2021. The law reauthorizes the Fixing America’s Surface Transportation Act, and includes a new pilot program to help states, cities, tribes, and other entities construct wildlife crossing structures that can improve wildlife migration and enhance habitat connectivity, while simultaneously improving driver safety. The new law also amends other federal-aid transportation programs to make them eligible to fund the development of these structures and calls for modernizing the science and research surrounding wildlife corridors and vehicle safety. Interested in learning more about national grants and other Federal, Tribal, and State funding programs that can be used to pay for wildlife mitigation measures, including animal road crossing structures?"

Oceana

Australia

Western Australia

• The Landowner Biodiversity Conservation Grants Program "provides financial support to Cockburn residents living in the rural, rural living and resource zones, who wish to conserve and enhance the natural bushland and wetland areas on their property." 

Further Reading