Great Lakes ice cover hits record low through mid-March of this year

Habitats

Meanwhile, in northwest Lake Superior sits the rugged, isolated Isle Royale. There, scientists have conducted one of the longest continuous predator-prey studies in the world, observing the interplay of moose and wolves since 1958.

But this year, several days of above-freezing temperatures left only a fine sheet of ice over the waters. Researchers were forced to depart weeks early to make sure their ski-plane could take off.

“It was very disappointing to not be able to continue the work,” said Sarah Hoy, co-leader of the project and a research professor at Michigan Technological University. “It’s really unprecedented.”

The ice itself forms part of the ecosystem. Wolves often rely on the ice cover, which is less taxing to navigate than uneven terrain, to move across the island.

“The ice makes a path of least resistance for wolves, so they do use those habitats,” Hoy said.

Elsewhere, the ice provides a sanctuary for different organisms. Ice algae, which help form the critical foundations of the food web, cling to the base of the ice cover. Whitefish, which are highly valued for commercial fishing, rely on ice as a protective buffer in spawning areas, scientists say.

In shallow areas, where whitefish scatter their eggs, the ice dampens wave action. A lack of ice could potentially affect their ability to reproduce.

“It could mean low recruitment, meaning a lot less whitefish entering into the population because they weren’t able to survive,” Murchie said.

The surging waves could also wreak havoc on beaches and bluffs, eroding the shore and even increasing flooding. Chicago is battling erosion and unpredictable lake levels on its 26 miles of public shoreline

.According to a 2021 study, between 2012 and 2019 the Chicago shoreline lost an average of nearly half the parts of its beaches that were not submerged. In January 2020, severe storms and high lake levels created one of the biggest threats to Chicago beaches in years, causing an estimated $37 million in damages.

“Ice essentially dampens high waves,” said Ayumi Fujisaki-Manome, an associate research scientist at the Cooperative Institute for Great Lakes Research at the University of Michigan, a collaboration with NOAA. “If you lose that ice protection, the shoreline will be exposed to high waves, so that in that sense, it’s true that loss of ice cover will lead to coastal erosion.”

What’s needed now, scientists say, is more research. Only when the ice cover is fully understood can solutions be implemented, scientists say.

“We probably need more investment to understand the net impact,” Fujisaki-Manome said.

Back at Rosewood Beach, Ricketts surveyed her surroundings: the gentle stream, the clear blue lake and a mound of granite slabs encircling the beach. The rocks were part of a 2015 renovation project aimed at reducing erosion on the lake bluffs.

“This is like a significant, unique ecosystem, which is threatened by wave action,” Ricketts said. “And without those ice formations, which are protecting the soil on our slopes, they are vulnerable.”

So many of the beach’s looming threats seemed to tie back to ice, she said. Changing migratory patterns, erosion, unpredictable water levels.

Often, she’s struck by the seeming inevitability of it all. “You can kind of get back in a mind space of like, ‘Are we doing enough?’” Ricketts said. “I don’t know.”

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