Eager for Beavers
Researchers in Paradise, Chapter 1
Inspiration Ridge Preserve is a hub for ecological research. While many research sites are remote and challenging to access, the Preserve provides easy access to an expansive and diverse area that has minimal human visitation or impacts. Since the Preserve was established in 2019, seven university graduate student research teams have partnered with the Center for Alaskan Coastal Studies to conduct a wide array of studies on the Preserve’s wildlife and ecosystems. In the years ahead, these partnerships will continue to thrive and grow.
In our Researchers in Paradise series, you can dive into the fascinating questions our research partners are investigating and learn about some of their research findings. In the first edition of this series, learn how researchers at the University of Michigan are investigating the disappearance of beavers in Fritz Creek watershed and whether the region is ready for the reintroduction of beavers.
Inspiration Ridge Preserve protects the headwaters of the Fritz Creek watershed. Photograph by Nina Faust.
Eager for Beavers
Certain wildlife species have an outsized impact on their habitats. These critters are referred to as keystone species. A particular kind of keystone species is an ecosystem engineer–a species that has the ability to build habitat other plants and animals rely upon.
Beavers are an example of a keystone species that serves as an ecosystem engineer. With each dam they build, they create ponds above, and varied stream habitat below. The impacts of this engineering is far-reaching, with implications for groundwater storage, stream temperature, peatland protection, and carbon storage. In addition, wildlife who require these different aquatic ecosystems count on beavers to make it for them. However, beavers were hunted to near extinction for their pelts, and the resulting habitat degradation has been far-reaching.
A tree girdled by a beaver will die and fall, given time, regardless of whether the beaver returns to finish the job. Photograph by Charlie Reinertsen.
Fritz Creek watershed, where Inspiration Ridge Preserve is located, is one of the many areas where beavers have been removed from the landscape. A team of researchers from the University of Michigan conducted a study to find out what would happen if beavers were introduced on this landscape.
The research team
Esther Chiang, Riley Glancy, Nikita Hahn, Hannah Hicks, Linfeng Li, Zhangyanyang Yao, advised by professor Ines Ibanez.
The question
Is Fritz Creek watershed a good candidate for reintroduction of the North American beaver?
The process
The University of Michigan research team used two tools to guide their field data collection process: the Beaver Restoration Assessment Tool and the Methow Beaver Project Suitability Scorecard. These tools helped them test whether Fritz Creek is a suitable site for beaver reintroduction, and to predict the density of dams in streams if beavers were reintroduced. The researchers studied and assessed the ecosystem, including measuring food availability for beavers, stream flow and gradient, historic beaver activity, and analysis of potential human interference.
Hannah Hicks and Linfeng Li measuring stream flow on an Inspiration Ridge Preserve creek. Photograph by Nina Fuast.
The results
The research team was able to show that the habitat of Fritz Creek is highly suitable for beavers. However, the researchers noted that beavers could present a challenge for landowners who might experience flooding throughout the watershed. As an initial step, the researchers recommended installing and studying the impact of a Beaver Dam Analog–a man-made dam that mimics a beaver dam–to ensure that the changes would be beneficial for the ecosystem.
Looking forward
With this positive report in hand from the University of Michigan team, the Center for Alaskan Coastal Studies hopes to partner with other Alaskan groups also working on beaver restoration. Already in the works is a project comparing ecosystems where beaver dams currently exist, where they are being removed, and where beaver dam analogs are being built.
Researchers from the University of Michigan pose for a picture in front of the Headwaters of Fritz Creek on Inspiration Ridge Preserve. Photograph by Nina Faust.