Meet #ScienceWoman Sheila Eyler

Celebrate Women’s History Month with us! This year, we’re looking forward by honoring women across the U.S. Fish and Wildlife Service and female conservationists who are making history in our agency and in conservation. With each #ScienceWoman, we’ll share a photo and a couple questions and answers about her work. Stay tuned for posts throughout the month!

Sheila Eyler coordinates our Mid-Atlantic Fishery Resources Office in Pennsylvania and recently earned a P.h. D. from West Virginia University studying the impacts of hydroelectric dams on fish migrations. Today she shares with us how her childhood experiences in the outdoors helped shape her passion for natural resources and her desire to be a fisheries biologist.

Sheila tagging female horseshoe crabs at Bowers Beach, Delaware. Photo credit: Robert H. Pos/USFWS

Q. How did you get interested in conservation? A. My family was in the wholesale live bait business and I grew up collecting fish and working in a bait shop. I enjoyed being outdoors and working on the small lakes and became interested in sustainable use of natural resources as a result of their commercial fishing efforts.

Q. What’s your favorite species and why? A. American eel. Although they are not the most attractive of critters, adult eels migrate thousands of miles to spawn in the Sargasso Sea. Young eels migrate upstream and are able to climb up dams or even leave the water and crawl in the grass to get around obstacles in the river.
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Bringing back American eels in the Susquehanna River

In today’s post, Sheila Eyler, project leader for the Mid-Atlantic Fish and Wildlife Coordination Office, shares her success in working with American eel populations on the Susquehanna River.

When deciding to attend graduate school, I must admit that the American eel was not on the top of my list of fish to study. However, an opportunity to evaluate the impacts of hydroelectric dams on eel migration helped make the decision for me.

Seven years later, what I have learned about this unique and often misunderstood “snakelike” fish species has made me one of its biggest fans.

Historically, eels were abundant in estuaries and freshwater tributaries in much of the eastern U.S. and Canada. The construction of dams changed all this, drastically limiting eel migration routes from the ocean to upstream freshwater areas.

As a fisheries biologist, I continually look at the impacts that a species’ decline has on an entire ecosystem. In the case of the American eel, the population decline has an important – and fascinating – connection to certain native freshwater mussel species. Larval mussels need to attach to the gills of a fish in order to complete their life cycle. Some mussel species specifically need American eels to survive.

Elvers climbing to base of Conowingo Dam on the Susquehanna River. Elvers are juvenile eels that migrate to brackish waters and begin to develop gray to greenish-brown pigmentation. Credit: Maryland Fisheries Resources Office, USFWS

With fewer eels headed upstream, mussel larvae have fewer hosts to help them survive. In rivers where dams have excluded eels for decades or longer, some freshwater mussel populations have also declined. Fewer mussels means poorer water quality because mussels have the ability to filter gallons of water a day.

Working on the restoration program for American eels on the Susquehanna River is never dull and continues to bring daily adventures. Along with several partner agencies, my colleagues and I have been trapping young migrating eels at the Conowingo Dam and stocking them into the upper watershed for several years. In 2013, we collected nearly 300,000 elvers (baby eels) for the restoration program.

Stocking eels has been very successful in the Susquehanna River. And to our delight, we are now finding eels with larval mussels attached to the gills, which will promote the growth of the mussel population.  

Watch American eels swim upriver

For me, it has been very rewarding to be part of this successful restoration program. I am proud to share the story of the American eel – an underappreciated resident of much of our freshwater streams with an amazing life cycle and connection to our environment.

For more information on the Susquehanna River American eel stocking program, read more at: http://www.fws.gov/northeast/marylandfisheries/projects/Eel%20passage.html.