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A Changing Ecosystem: Insects of Elwha Valley

As the largest dam removal in U.S. history brought Pacific salmon back to Washington State’s Elwha River for the first time in nearly a century, scientists were also thinking about how the changing ecosystem would impact what they consider the most important foundational group of Elwha Valley dwellers: insects.

Video by Matt Haugen/WSU News.

Last spring, entomology professor Richard Zack returned from Seattle to Washington State University with what is likely millions of specimens collected prior to the removal of the 100-year-old dam in Olympic National Park. He is leading a project to help sort, curate, identify, and create a database of the insects to provide insight into how the Elwha Valley ecosystem will change in the next several decades. Changes in insects will play a key role in how the new ecosystem develops.

“The Elwha is a fabulous research opportunity because it is a rare before and after study,” Zack said. “Understanding what is expected to be a 30 to 40 year trajectory of recovery will require comparing the pre-removal ecosystem with species changes and their abundances as recovery proceeds.”

Bioblitz for Bugs

Laura Hamada, a biology student, prepares to pin an insect in the entomology lab at WSU.
Laura Hamada, a biology student, prepares to pin an insect in the entomology lab at WSU.

The insect collection was part of a long-term, large scale project conducted by researchers from the University of Washington and the National Park Service, explains Jerry Freilich, research coordinator for Olympic National Park and partner on the project. The ATBI, or all taxa biotic inventory, aimed to collect aquatic and riparian invertebrates and non-vascular plants in the Elwha drainage.

“When the removal of the dams began we knew everything was going to start changing,” Freilich said.  Park Service biologists were already looking at larger plants and animals in the Elwha Valley “but a study was needed to find and identify the smaller, often overlooked organisms that make up the ecosystems foundation.”  This is one of the first studies that will not only look at the more “charismatic meagafauna,” Freilich said, but “also the microfauna.”

After the collections were made, Freilich connected with Zack to begin classifying the insects. “If you want entomology experts in the Pacific Northwest, WSU is where you go,” he said.

Training Future Scientists

But where do you start when you have hundreds of thousands of bugs to organize? With the beetles, said WSU biology student Laura Hamada, who plans to pursue insect taxonomy. Hamada and fellow student Noah Austin, a WSU student double majoring in physics and music, work in a lab in the entomology department where they are beginning to sort, prepare and identify the aquatic bugs, caddisflies, mayflies, stoneflies, true flies, and beetles.  Eventually, most of these specimens will be sent to specialists for specific identification.

“Noah is a pinning machine,” Hamada says as they work in the lab. While still in the beginning stages of sorting the insects by order or family, they have each pinned hundreds of insects.

Laura Hamada, a biology student, and Noah Austin, a physics and music student, talk about the insects in the lab.
Laura Hamada, a biology student, and Noah Austin, a physics and music student, talk about the insects in the lab.

The project serves as a training opportunity for young scientists and a resource for observing the changing biodiversity of the Elwha region. The collection will also be the first to provide information on the biodiversity of Olympic National Park, one of the most geographically interesting regions of the US, said Zack.

Preparing to Look Back

The dams, built in the 1900s, created still reservoirs of water that changed the Pacific Northwest system dramatically. Now that the water is again free-flowing, river and stream-dwelling insects are expected to return to the valley, Zack said.

This spring at Elwha, Zack will meet with entomologists, biologists, researchers and other partners on the project, including those classifying butterflies and spiders, to discuss how they can best use the collections to understand the impacts that removing dams have on ecosystems.

The insects collected for the project will join the 3 million specimens already housed at the M.T. James Entomological Collection at WSU. The project is funded by a two-year $30,000 grant from the Katz Memorial Foundation and conducted through the WSU Agricultural Research Center in the College of Agricultural, Human, and Natural Resource Sciences. Learn more about entomology at Washington State University at