Bigger than beakers

Researchers have a new way to study Lake Erie thanks to a facility at The Ohio State University Stone Laboratory that is the first of its kind on the Great Lakes. 

Stone Lab’s Mesocosm Facility, which opened in 2022 on South Bass Island, is the first open-air mesocosm on the Great Lakes and allows scientists to research environmental issues facing the lakes at a previously unavailable scale. Stone Lab is a part of CFAES. 

The facility contains 15 600-gallon tanks called “mesocosms” that researchers are using to study organisms ranging from algae and bacteria to adult fish. The tanks pump in water from Lake Erie to replicate the natural environment on a larger scale than what’s possible with “microcosms” such as beakers, bottles, or fish tanks. 

“It allows us to do research that wasn’t possible before,” said Justin Chaffin, research coordinator at Stone Lab. “We’ve been doing small-scale experiments for years, but we can’t do controlled experiments out in the lake. So, the Mesocosm Facility allows us to do research that can be better extrapolated to the natural system.” 

He said mesocosms help eliminate artificial results that pop up in small-scale bottle experiments. 

“It’s more exposed to the elements,” Chaffin said. “You get the natural sunlight, cloud cover, rain, wind. Everything that’s happening in the lake can influence what’s happening in the mesocosm when it’s an outdoor facility.” 

The mesocosms can function with water flowing to and from Lake Erie, or they can serve as batch culturelike experiments. Filters are available to remove particles down to the size of a micron—one-millionth of a meter. 

This summer, scientists used the facility to study how smallmouth bass respond to changing climate and to determine the impact federally registered algaecides have on zooplankton, small shrimplike creatures that are important food for fish. 

Chaffin anticipates demand for the facility will grow. One goal is to equip the tanks with improved, automated instruments that monitor temperature and dissolved oxygen and report data every couple of minutes. Another goal is to create similar outdoor facilities at other field stations around the Great Lakes. 

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