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Environmental Review Toolkit


Arizona Department of Transportation: Arizona Wildlife Linkages

Planning and Environment Linkages: State DOT Institutional Mechanisms

The Arizona Department of Transportation (ADOT) and partner agencies are working together to discuss, analyze, and address wildlife management concerns early in transportation and resource planning, and to carry information and decisions into project development, design, and construction.

Map showing Arizona's Wildlife Linkages


In the past, wildlife management concerns were incorporated into projects as issues were identified and when project plans were already well underway. This often led to costly redesigns to accommodate issues identified late in project development. In 2003, the Arizona State Route 260 project encountered difficulties addressing wildlife management concerns early in project development. ADOT and resource agencies recognized a need to consider wildlife management concerns earlier in their processes to better protect wildlife, address safety issues, and improve coordination among agencies.

Now, wildlife management issues are being addressed in planning and in the early stages of NEPA through use of the Arizona Wildlife Linkages map. With this tool and resource agency coordination, ADOT can identify potential infrastructure funding needs early and it can avoid costly delays and redesigns. Developing better wildlife crossing designs based on local conditions can also increase safety for humans and wildlife.

Wildlife Linkages Working Group

The Arizona Wildlife Linkages Working Group was formed as a bottom-up effort starting at the staff level. Nine agencies partnered together to form the Working Group, including the Federal Highway Administration (FHWA), USDA Forest Service, Bureau of Land Management, ADOT Divisions, Arizona Game and Fish Department, and non-profit organizations. The ADOT Natural Resources Management Division and the Arizona Game and Fish Department lead the effort.

In 2004, the first workshop was held with over 300 participants from many fields, including biologists, engineers, and planners. The goal of this kick-off event was to identify critical linkages that connect habitat blocks throughout the state.

Wildlife Linkages Map

Through a series of meetings, the Working Group developed a Wildlife Linkages map for use in both conservation and transportation planning, including long-range transportation plans, corridor plans, and for mitigation.

The map is used as a decisionmaking tool locally and statewide. Corridors, areas of habitat fragmentation, and private land that cannot be accessed by the state are identified on the map, which is organized into eco-regions or habitat blocks. However, only known habitat areas are marked. The map is currently used in the later phases of existing projects but will be encouraged as a tool during the planning of new projects. For example, when environmental planning staff see new projects at planning meetings that have potential wildlife impacts, they inform the ADOT Natural Resources Management Division of the need for wildlife linkage review. The map is also used as a model for counties and cities as they develop conservation plans and master plans.

ADOT has recently begun studying the map's linkage zones at the county level and will be working with counties to ensure that the map is accurate. In the future, ADOT would like to inventory existing infrastructure and use the map to identify retrofitting opportunities. The Working Group may also hold future workshops to update the map.


ADOT worked with Arizona Game and Fish Department, USDA Forest Service, FHWA, and other partners to incorporate wildlife considerations in the reconstruction of State Route 260. ADOT researched and implemented designs such as natural rock and earthen fencing (rather than concrete) to funnel elk and deer toward underpasses. The new infrastructure has lead to an 85% reduction in wildlife-vehicle collisions near "hot spots" of wildlife activity on the Christopher Creek section of the highway.

Lessons learned from research and coordination efforts in State Route 260 are now being applied early in transportation planning through the Wildlife Linkages working group, assessment, and map. For example, on the US 93 highway expansion project, ADOT worked with Federal and state agencies to incorporate mitigation throughout planning and project development to protect flora, fauna, and unique landscapes.


There is limited staff available to update the linkages map or to inventory infrastructure for future retrofitting, as well as limited funding to monitor and identify habitat issues. In addition, most grant funding tends to protect large animals and endangered species, which can limit the focus on developing contiguous habitats for other species.

Lessons Learned

The Wildlife Linkages map is a tool to inform decisionmaking, but should not be used alone. For example, some areas may have habitat issues even if they are not marked on the map. The map can help transportation and resource agencies identify potential concerns for further discussion and analysis. For the process to be successful, it must be collaborative, with agencies taking ownership. Members of the Wildlife Linkages Working Group are equal partners, with both transportation and resource agencies leading the effort and working together to protect wildlife and inform planning and project level decisionmaking.

Future performance measures may focus on the efficiency of wildlife crossing structures to determine their role in the number of collisions. Expected benefits from this pro-active approach to wildlife conservation include cost savings and reductions in wildlife-vehicle collisions and fatalities through better design decisions earlier in planning and project development.

The Arizona Wildlife Linkages effort has been recognized through multiple state and Federal awards, and other states have asked Arizona to share their methods.

For more information on Arizona Wildlife Linkages, visit

For more information, contact:

Todd G. Williams, M.Sc.
Director – Office of Environmental Services
Arizona Department of Transportation
Phone: 602-712-8272