Marine Sciences student aims to make difference through cutting-edge research

Katie Dimm
Katie Dimm (Marine Sciences, ’22) scuba dives with sharks, her research passion.

“Research is my passion. It is the core of what I love about marine science,” explained Katie Dimm (Marine Sciences, ’22).

Dimm discovered her passion at her high school in Ridgefield, Connecticut.

“During my sophomore year, I took a course called Science Research. All the students in the course had the chance to do independent research, which was a huge jumping off point for me,” Dimm said. “I became really interested in studying levels of methylmercury, an organic form of mercury that is highly toxic and accumulates in aquatic environments and, in particular, sharks.”

After high school, Katie took a gap year to attend Cape Eleuthera Institute, which is devoted to research, education, and outreach on the Cape Eleuthera peninsula in the Bahamas.

There, she was able to carry on her shark research and assist with a large array of projects, such as the collection of Caribbean spider crabs, shark tagging studies, and sea cucumber and coral reef surveys.

It was also during this gap year that Katie discovered UNE.

“I learned about the research opportunities available there, toured the campus, and fell in love with the place,” she said. “What I liked most was that I wouldn’t have to wait to carry out research. I could continue the research I had been working on in high school and in the Bahamas with the guidance of my UNE professors.”

Katie started working with Stephan I. Zeeman, Ph.D., professor of marine sciences in the School of Marine and Environmental Programs, who was particularly supportive of her research — especially when she needed to create a controlled environment to further her research, including a study of why larger sharks do not always have higher concentrations of mercury than smaller sharks.  

“Long living apex predators like sharks seem to have an incredible capability to accumulate and handle massive concentrations of mercury, making them phenomenal biomarkers for mercury in ecosystems. However, there is a lot of inconsistency in the mercury levels found in various species of sharks,” Dimm explained. “Research has shown that factors such as the depth in which the sharks forages, their metabolism turnover times, and if they are warm-blooded or cold-blooded could all impact mercury levels. There are many different factors to consider, and, unlike other research, you can’t really keep sharks in controlled environments.”

Working with Zeeman, Dimm set up her own lab within UNE’s Marine Science Center, working with green crabs to further her research. “By using baseline organisms to analyze how lower level concentrations of mercury might start to affect the bottom of the food chain, I can hopefully theorize about what could be happening as we move up the chain,” she said.

Dimm is also engaged in research with John A. Mohan, Ph.D., assistant professor in the School of Marine and Environmental Programs. The research entails using a new methodology to examine mercury tracers at each individual level of the sharks’ vertebrae to map its accumulation rates over time.

“This is something I’m really excited about because it, to the best of my knowledge, hasn't been done before, and it could be monumental in terms of finding a way to look at mercury exposure over a long period of times,” Dimm said.

When Dimm is not in the lab, she acts as president of UNE’s Scuba Club. She credited her professors for her success in and out of the classroom.

“The faculty at the Marine Science Center are so supportive, and their support has shaped my experience,” said Dimm. “With their collective expertise, I have been able to carry out cutting-edge research that I know will have an impact on our understanding of methylmercury accumulation in our aquatic systems.”

Tiger shark
Katie Dimm ’22