Creating native wildlife habitats on pipeline rights-of-way

While attending graduate school at Pennsylvania State University (Penn State), Dr. Carolyn Mahan joined her advisor on a biodiversity study on transmission lines.

The study’s goal was to find ways to manage the vegetation under electrical utility lines, initially finding ways to keep tall trees out of rights-of-way, but also to encourage biodiversity.

The conservation of biodiversity includes encouraging native plants, pollinators, breeding birds, as well as butterflies, ground beetles and game species.

A right-of-way is a type of legal land easement that may be established to permit the construction of infrastructure such as pipelines, electric transmission lines or roads.

Dr. Mahan is still involved in that biodiversity project, and some could say it helped lay the foundation for her work today. She moved on to other research areas after graduate school but came back to this line of research in 2014. She has been working as a principal investigator on rights-of-way research for approximately the past 10 years.

As a professor of biology and environmental studies at Penn State University – Altoona (Penn State Altoona), Dr. Mahan teaches courses in environmental studies and runs a program which uses interdisciplinary learning to solve environmental issues. Interdisciplinary approaches are critical to solving complex environmental problems with a variety of partners—including industry.

From transmission lines to pipelines

While Dr. Mahan was working on the transmission lines right-of-way project, Penn State Altoona held a summit and invited energy companies to partake. At that time, Dr. Mahan met Donnie Garrison from Shell Pipeline Company LP (Shell Pipeline), who inquired if the research she was conducting on electric transmission lines could be applicable to pipelines. Her simple answer: yes. That initial conversation led to the creation of the Falcon Conservation Project, focused on enhancing the biodiversity and habitat management along the Falcon Pipeline right-of-way running parallel to the Montour trail in Washington County, Pennsylvania—a 30-acre section that is part of the 97-mile common carrier ethane pipeline, owned and operated by Shell Pipeline.

Shell Pipeline and other energy companies manage about 30 million acres of rights-of-way in North America. Dr. Mahan’s philosophy is that if you can take those millions of acres of pipeline rights-of-way, and promote native plant communities, it could be a game changer for creating native habitat for wildlife that the ecosystem and, in fact, humans depend upon.

Turning data into information
Dr. Mahan was seeking a company that was going to be interested in research, not just good press. Shell Pipeline helped the Penn State research office design a project on Shell’s Falcon Pipeline to look at different types of treatments on pipelines and how biodiversity responds to different ways of managing vegetation. For Shell Pipeline, it was a good case for implementing best management practices for a right-of-way. It then evolved into a great opportunity for research.

Dr. Mahan and her team began year one of research on Shell’s Falcon Pipeline with preliminary sampling and surveying work over the summer. They discovered rare native plants, monarch butterflies and grassland birds (some of special conservation concern) utilizing the right-of-way habitat, which she finds promising for the rest of the conservation project.

This three-year research endeavor is part of Shell Pipeline’s Right-of-Way Conservation Program. A final report and presentation to research partners will take place in June 2027 with management recommendations and implications for future research discussed.

Turning information into insight
Dr. Mahan hopes that the results of this research will equip other companies to implement these management techniques across the landscape, potentially creating large, vast connective habitats across the country.

Historically, the most common practice for maintaining rights-of-way on gas pipelines is regular mowing. Mowing can be easier to maintain, and easier to comply with regulations since vegetation will be short. Other management practices include high volume, non-selective application of herbicides, frequent mowing or mulching.

This research seeks to change that view by implementing selective application of herbicides to non-compatible plants only and/or implementing conservation mowing approaches—all part of integrated vegetation management.

Dr. Mahan hopes her research findings will be an example for other companies to follow in pursuit of their own environmental, social and governance goals. The research also could encourage more public participation and partnerships to promote managing rights-of-way for biodiversity.