Tag Archives: otoliths

Field Samples: Fish Earbones Tell Story of Kingston Coal Ash Spill

In this addition of our weekly Q&A asking researchers what they’ve been up to and what they’ve learned, Brenda Pracheil, a former CFL post doc and current research at the Oak Ridge National Laboratory, talks fish earbones, coal ash, and environmental monitoring.

Who are you, where are you from, and how did you get to where you are now?

Pracheil once wrangled big fish on big rivers. Now she studies smaller structures in a big lab.

Pracheil once wrangled big fish on big rivers. Now she studies smaller structures in a big lab.

My name is Brenda Pracheil and I am a research staff member at Oak Ridge National Laboratory in Oak Ridge, Tennessee. I am originally from South Sioux City, Nebraska—a town of about 10,000 people in the northeast corner of the state where Nebraska, Iowa and South Dakota meet. I have done a lot of research on fish and large rivers which is an interest that probably stems from growing up on the banks of the Missouri River and spending a lot of time fishing with my grandpa when I was a kid.

My path to where I am now has been circuitous one. All told, I have received training from five colleges/ universities including three undergraduate institutions (University of Nebraska-Kearney, Western Iowa Tech Community College, University of Nebraska-Lincoln) before finally graduating with a BS in Biological Sciences and BA in Philosophy. I also attended two universities for grad school (MS: Michigan State University, Zoology, PhD: University of Nebraska-Lincoln, Natural Resources), and held postdoctoral positions at two universities (University of Wisconsin-Madison, University of Nebraska-Lincoln). I joined the staff at ORNL in January 2014.

Pretend we just boarded an elevator and you only have a one-minute ride to tell me about your work. (in this case, otolith related stuff). Can you capture it a few sentences?

Much like trees, the rings of an otolith can help researchers determine the age and growth rate of a fish.

Much like trees, the rings of an otolith can help researchers determine the age and growth rate of a fish.

Fish earbones, or otoliths, are one of the most incredible structures in the animal kingdom because they not only form rings on them every year (like rings on a tree) that can tell us how old a fish is and how much it grew in a year, but they can also tell us where a fish has been. Fish otoliths incorporate the water chemistry signature of their habitat that allows us to see the chemical fingerprint of the environments where they lived. These techniques have frequently been used to determine migratory history of fishes; something that we have done with my past work in Wisconsin.

My ongoing work with otoliths at Oak Ridge National Laboratory uses otolith microchemistry to understand the impact of an environmental disaster (Tennessee Valley Authority Kingston Coal Ash Spill) on a riverine ecosystem. For this study, we will use otolith material that was formed prior to and after the disaster, allowing for a comparison of pre-spill and post-spill environmental contamination. Practically speaking, the pre-spill/ post-spill snapshots of contamination enable us to assess progress in clean-up efforts. Continue reading

Fish Fry Day: Video Explains Earbones

Just thought we’d share this excellent little animation explaining what an otolith is and what one can tell fisheries researchers. Credit goes to the folks at “From Reefs to Rivers,” Florida’s Fisheries blog for this little tidbit of science communication.

We here at the CFL use otoliths for lots of research, especially on freshwater fish migrations.

Tracking Northern Pike in Green Bay

CFL grad student, Dan Oele, is trying to see if pike return to their “birthplace” to spawn or if any ol’ tributary will do. Thanks to funding from the Great Lakes Restoration Initiative, Oele is out in Green Bay working on an answer. Watch (or read) below:

GREEN BAY — It’s the second day of April and Dan Oele is cruising the tributaries of Green Bay on the hunt for northern pike. Continue reading