NASA joins the ranks of ‘beaver believers’

It was quite an unexpected headline from NASA this past summer: Researchers Become “Beaver Believers” After Measuring the Impacts of Rewilding.

NASA – the space agency? Yes, it turns out that NASA keeps a close eye on earth, too. They track water; they track food production; they collect an amazing cornucopia of data. And part of that tracking is remotely observing the power of rewilding by beavers in Idaho, helping show which streams can support beavers and monitoring how water and vegetation change if they return.

Beaver dams mean water disperses and stays longer on the land, supporting more plants and creating ponds and meadows. Such restored ecosystems provide good habitat for salmon and trout, and sage grouse and mule deer, as well as more fresh drinking water and better grazing landfor cattle. And they make the land more resilient to fire and drought.

Cory Mosby of Idaho Fish and Game says that remote sensing data helps them monitor more areas and quantify those positive changes. “We’re going to see a wider green vein later into the year and we will see more water later in the season,” he told NASA. “I’m not aware of another species that does this (save humans) on the scale that a beaver population can,” he told Mongabay.

Already, the program has produced images from space of how areas with reintroduced beavers are greener than areas without them.

Boise State News

In 2018, when Jodi Brandt received a grant from the US Department of Agriculture to use new satellite data to map water in semi-arid regions like Southern Idaho, she discovered an unexpected theme as they talked with farmers, ranchers and officials – “beaver fever.” It is the term given to those who have been promoting reintroducing beaver in the U.S., Europe and Canada for years.

Beavers covered the land when Europeans arrived. But they were hunted almost to extinction and that, unknown to trappers, vastly changed North American  ecosystems from sea to sea. Western riverscapes used to be much more complex and interconnected, says Nick Kolarik, who works with Brandt. By significantly slowing the water, “sediment is stored, water infiltrates into the aquifers, riparian vegetation establishes, habitat is created, and carbon is stored,” he says.

Jodi Brandt

Idaho cattle rancher Jay Wilde began stream restoration with beaver rewilding in 2014. By 2022, he was a “beaver believer.” Now there are more than 200 beaver dams along Birch creek near Preston, Idaho, and the stream flows 40 days longer into the year.

Wally Macfarlane of Utah State University, who worked with Joe Wheaton to develop the Beaver Restoration Assessment Tool (BRAT), points out that:. “Prior to beaver trapping, beaver dams were just about everywhere in the west. So what we’re attempting to do is to bring beaver dam densities back to historic levels where possible. In doing so, we’re building important drought resiliency and restoring stream areas. I think there’s a lot of foresight by NASA realizing how these things connect.”

Brandt’s team is focusing on Idaho and nearby regions because, while wet ecosystems comprise only 5% of the landscape, those areas are critical for more than 90% of species living in the area during the dry season, NASA says. 

Adding water and vegetation data from NASA missions addresses two major challenges: how to quantify change over time and how to consistently monitor large areas. NASA’s fleet collects data across large areas of the world and pass over the same areas regularly and across seasons so researchers can observe an area in real time and also look back to the  past. So Brandt’s team is turning data from Earth science missions like Landsat and Sentinel into information that more people can understand and use.

NASA Applied Sciences’ Ecological Conservation program funds the beaver rewilding project. Associate program manager Cindy Schmidt recently joined the team in Idaho to build beaver dam analogs—temporary, human-created structures which help beavers get established in an area. After seeing how the beavers benefited the land, “I became a beaver believer,” Schmidt said.

The project includes four parts: updating the existing Beaver Restoration Assessment Tool, creating two applications using Earth observations to measure beaver rewilding impacts, and a smartphone application for comparing photos of field sites.

The current project runs through 2025 and aims to make the tools easy to use for a variety of decision makers. Beyond that, the team has their sights set on expanding to nearby states that have similar terrain and water management strategies.


Researchers Become “Beaver Believers” After Measuring the Impacts of Rewilding. NASA, Jul. 17, 2023

NASA satellites reveal restoration power of beavers Mongabay, Sep. 11, 2023

For water in the faucets, you need beavers in the mountains Hopebuilding  blog, Jul. 8, 2021

The beavers are back! A win for beavers could be a win for ranchers and biodiversity in rural Idaho. Boise State News, Dec. 5, 2022