Water Resources Center

The Water Resources Center is affiliated with the College of Food, Agricultural and Natural Resource Sciences and University of Minnesota Extension.

NRRI receives $1 million to monitor deeper into the Great Lakes

by June Kalestad, Natural Resources Research Institute, University of Minnesota Duluth

Scientist Amy Kireta should be enjoying the cruise—satellite television, high-speed internet, three delicious meals prepared daily, exercise room—not a bad gig for a researcher on a month-long sampling expedition this spring in the heart of the Great Lakes. Unfortunately, there’s no escaping sea-sickness and storms.

Kireta, phytoplankton specialist from the University of Minnesota Duluth’s Natural Resources Research Institute (NRRI), worked this spring aboard the Environmental Protection Agency’s research vessel, Lake Guardian. The collected single-celled phytoplankton (algae) and zooplankton (microscopic animals) are going to supply reams of information about changes taking place in the waters of the Great Lakes. So at all hours of the day and night, sea sick or not, the scientists get a 15-minute warning to don steel-toed shoes, life vest and hard hat before reaching their next sampling station.

NRRI received a $1 million grant from the Environmental Protection Agency to play a significant role in collecting water quality data from the Great Lakes. Kireta and lead scientist Euan Reavie will use the algae to provide long-term information on the impacts of invasive species, excessive nutrients, and possibly, climate change in the lakes. The five-year project will investigate how these lowest links on the food chain are faring in the face of human disturbance. Reavie and Kireta will gather, identify, sort, and count thousands of species of microscopic algae.

“Algae are a critical piece of the Great Lakes food web and can track the impacts humans have had—and will have—on fisheries and the lake ecosystem,” Reavie explained.

Algae were used as indicators of the Great Lakes coastal zones during NRRI’s recent Great Lakes Environmental Indicators project, but sampling in open water is fundamentally unique— the water moves mightily and the impacts are more diffused. Unlike localized coastal disturbances, results in the open water track whole-lake impacts.

Kireta uses a rosette sampler (see photo) to collect phytoplankton samples from the surface down to 65 feet below. The open waters and 6-to-10 foot waves could be a challenge, but the Lake Guardian and their tools are built for the task. And, Kireta added, “We have an experienced captain who keeps us pointed in the best direction and over the correct GPS point.”

Once the samples are in the lab, the microscopic work begins. The soft algae are analyzed separately from the diatoms which have cell walls made of biogenic glass. This is followed by seemingly endless data compilation and analysis. The data are transformed into answers for critical ecological questions, like “How have we impacted the quality of the Great Lakes?” and “What does the future of the food chain look like?”

This research is part of a vast, multi-disciplinary team of scientists, government officials and public representatives whose goal is the protection and restoration of the largest single source of fresh water in the world.

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Amy Kireta and EPA Chief Scientist Glenn Warren send the
sampler off the side of the Lake Guardian. The sampling
equipment is a SeaBird 911 CTD(conductivity, temperature,
depth) with a Rosette water sampler, sensor pump,
fluorometer, transmissometer, altimeter, PAR
(phyto-synthetically active radiation), pH, and dissolved
oxygen, with GPS interface. Photo courtesy of NRRI

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A collage of diatom species from lakes Michigan, Superior
and Huron. Photo courtesy of NRRI