As pollinators have declined in the United States, interest has increased in managing existing roadside habitat or creating additional habitat to support them. In particular, state Departments of Transportation are seeking strategies to implement voluntary conservation practices to help recover imperiled species and reduce the likelihood that additional species will be listed under the Endangered Species Act (ESA), and then to be in compliance with the ESA if a species becomes listed.
The value of roadsides for the conservation of listed and imperiled pollinator species can be substantially increased in several ways, including changes such as adjusting seed mixes, mowing schedules, herbicide use, and other roadside management strategies. However, specific guidance and information relevant for the regional diversity of imperiled pollinator species, habitats, and roadside maintenance practices has not been compiled. To address this need, the National Cooperative Highway Research Program Transportation Research Board has funded this project (NCHRP 25-59), resulting in 16 regional guidebooks for Pollinator Habitat Conservation along Roadways. The guidebooks cover all 50 states to support Departments of Transportation (DOTs) in ESA compliance, as well as in creating, enhancing, and maintaining pollinator habitat along roadways, and will be published in 2023.
The content of the guidebooks was derived from a thorough literature review of research, surveys, and a peer exchange workshop attended by over 200 people representing 41 states. The surveys gathered input from leading pollinator and roadside revegetation researcher experts from across the United States to ensure the most current science from each region was included in the guidebooks. DOT staff from around the country provided input on current practices used that may benefit pollinators, as well as barriers to implementing particular practices, and other information about roadside management and maintenance related to pollinators. Our talk will summarize our findings from the surveys and peer exchange meeting, describe how to access and use the regional guidebooks and associated implementation tools, and will review additional research needs identified by the project.