Conservationist swabs fish to study long-term effects of harmful algal blooms on Lake Superior Meet Kasey Benesh

There is amazing diversity among aquatic species in Lake Superior, but Kasey Benesh did not begin her journey there. She spent her childhood in New York, not far from the ocean at Long Island. She grew up to earn her bachelor’s degree in organismal biology with a concentration on conservation from Auburn University, and then her master’s degree in biology with a concentration in conservation from Central Michigan University.

During undergrad, Benesh was a fellow at the Tennessee Aquarium Conservation Institute studying endangered fish and learning about Tennessean and Alabaman fish diversity. After earning her master’s degree, she moved to Florida to study neuroanatomy and brain morphology in Mexican blind cave fish before becoming a part of the Environmental Protection Agency’s (EPA) Office of Research and Development (ORD) Program in Duluth, Minnesota.

Under the mentorship of ecologist Aabir Bamerji, Benesh is part of the Ecosystem Services Branch at the Center for Computational Toxicology and Exposure’s Great Lakes Toxicology & Ecology Division laboratory. Here, Benesh is studying harmful algal blooms (HABs) that are caused by cyanobacteria. Among other things, these HABs can cause once clean, oxygenated water to be filled with dangerous toxins and pockets of hypoxia, meaning oxygen deficiency. While HABs form naturally, they can also be exacerbated by human activity that increases the offending algae’s food supply, such as water runoff containing fertilizer or sewage. Benesh is looking at how HABs may alter the microbiome on fishes’ skin, specifically in the mucus coating, changing how they defend themselves against disease.

“Changes in environmental conditions associated with HABs can upset the delicate balance, which in turn can leave fish vulnerable to infection by opportunistic pathogens and impact overall fitness,” explained Benesh.

Benesh and the team collected samples of yellow perches and water from Lake Superior in places where HABs are recurrent. To do this, they use a method called electrofishing to temporarily stun fish, swab them and then release them unharmed. Benesh was excited to see what kind of huge fish live in the unseen depths of Lake Superior and, while taking field samples, even got to see a muskellunge that was the size of their boat.

Benesh will extract DNA from the samples and compare it to data from previous years to see if there is a difference in the fishes’ microbiomes. The study’s goal is to look at the long-term impact of HABs on the aquatic ecosystem, particularly on the fish that call it home.

In addition to sampling on Lake Superior, Benesh is assisting the Lake Superior Algal Bloom and Nutrient Subgroup to bring public awareness of algal blooms. “I was surprised to find many people were unaware of the algal blooms happening right in their backyard,” said Benesh. “I helped publish a Bloom Bulletin to report on algal blooms in Lake Superior each year to keep people informed.” She also organized a science, technology, engineering and mathematics (STEM) symposium for the Twin Ports Early-Career Researchers (TPER) group.

Benesh has presented HAB research not only for TPER but also in-person at the Ecological Society of America Conference in Portland and remotely at the State of Lake Erie Conference. Benesh has also co-authored a review paper on HABs in the journal Ecologies called “Incorporating Microbial Species Interaction in Management of Freshwater Toxic Cyanobacteria: A Systems Science Challenge.” Later this year, Benesh will be first author on an article slated for the Lake Erie Special Issue of the journal Aquatic Ecosystem Health and Management, reporting the results of a multiple-agency study of stable isotope data from HABs in Lake Erie.

Benesh plans to continue being involved with conservation after completing her fellowship, thanks in part to seeing the fish diversity across the United States firsthand, from New York to Tennessee to Florida and Minnesota. She recommends the EPA program to others.

“I am incredibly grateful for the opportunity to grow as a researcher and communicator of science. I think my favorite part is the freedom to explore new skills and topics, and being able to design an independent research project,” said Benesh. “I have learned so much and met so many amazing people during my two years in the program.”

The EPA ORD program is administered by ORAU through its contract with the U.S. Department of Energy (DOE) to manage the Oak Ridge Institute for Science and Education (ORISE) and established through an interagency agreement between DOE and EPA.