Glenn Warren

Environmental Scientist
Research Institution: U.S. EPA/Great Lakes National Program Office
Home state: Illinois
What got you interested in science and how did you end up as a Great Lakes scientist?

I don’t remember when I got interested in science. I read a lot of science fiction as a kid. Does that count? Growing up near Lake Michigan might have influenced me. I swam and fished in the water and walked its beaches, except when alewives piled up on the shore a foot deep. I wondered why that was happening, and why there were nasty mats of algae on the shore in certain years. In college natural resources were, initially, my main interest and seemed like the easiest thing to study to understand what went on in the water of lakes and streams. Three college professors each had a great influence on my decision to work on water and the Great Lakes. I am grateful to them. I continue to be amazed at how we can influence these large lakes through our activities and by the things we put into the water.

Describe your research related to the Great Lakes.

Most of the research that I do on the Great Lakes centers around two things, the ecology of the plankton–the tiny plants and animals that drift with the lake currents–and using images produced by satellites to estimate what is going on in the lakes at a large scale. We have been collecting plankton samples and data on the Great Lakes since 1983. There have been large changes to the plankton community during that time, and it is important that we understand why these changes happen and whether or not what we humans do has any influence on improving or worsening the ecology of the lakes.

There are a few reasons for the changes we see in the plankton. Among the most important are the amount of nutrients we put into the lakes and the invasive species that have been introduced to the lakes by human activity. We have done a good job, in most places, of cutting back on nutrients. However, the introduced zebra and quagga mussels have changed the lakes and getting rid of them will not be easy.

Describe an experience you have had working with educators or the community. What was something that surprised you or that you especially enjoyed about the experience?

I am always impressed by the amount of enthusiasm and the resourcefulness of the teachers on our CGLL teacher cruises (aka, Shipboard Science workshops). Many science teachers have projects and programs at their schools that let students do hands-on science. They go beyond what is expected of them, making science relevant. The group of teachers on Lake Michigan in 2015 were real problem solvers. The research that I planned used video from a GoPro camera that was attached to a sled which was pulled behind the ship, skimming along the lake bottom, at specific points on the lake. We were looking at how much of the bottom was covered by quagga mussels at different depths. Analyzing the video frames with Photoshop really didn’t work, and the teachers came up with a way to estimate mussel coverage by having two people look at many video frames one-by-one and calling out the percent covered. It was difficult, but it was a way to get good data when the first method failed. And it is how science works.

I also think teachers could benefit from using special scientific equipment to help with science education. One of my attempts at addressing this need was purchasing 4 water quality data sondes (an instrument that measures water quality parameters instantaneously with sensors) to loan out to educators. This idea has morphed into the LimnoLoan program that EPA jointly runs with Illinois-Indiana Sea Grant (

Why do you think it is important for scientists to share their research with educators?

Scientists seem to be viewed as aloof and disconnected from normal life. It is important educators know that’s not usually the case. Scientists care about the work they do and how it effects the environment and people. Educators need to know that and to participate in science experiments and research projects to refresh their understanding of how science works so that they can pass that knowledge to their students.

What do you think are the most critical skills for students interested in a career in science?

Maybe the most important skill to develop, whether or not you want to be a scientist, is thinking—using your mind. Of course, memorizing is very important, we do a lot of it and that helps us recall facts we need to know for life, but being able to use those facts to help solve problems, is using your mind. It takes training to do it. The other skills that help you are math and the sciences.

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