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They weren't actually bugs, though they looked like them; they were macro-invertebrates, about a half a centimeter in length. What sets them apart is they are glacial relicts, meaning bugs left over from the glacial period that can only survive in really cold and really dark environments. The invertebrates have stayed in existence by finding only the deepest and cleanest spots to survive, like the inland lakes in Northern Michigan.

A study conducted in 1978 by some scientists at the University of Michigan proved these different glacial species lived in the bottom of eight deep inland lakes, and there is considerable data on some of the relicts in the Grand Traverse Bay. But nobody had ever researched how many were in Elk Lake, Torch Lake and Lake Bellaire.

"Despite their tininess, they're really important,"said Norton Bretz, executive director of the TLA. "One worry is these bugs are disappearing in Lake Michigan."

The macro-invertebrates are the lowest part of the food chain and are essential for the survival of other fish.

Bretz, a former research physicist at Princeton for 29 years, came up with the idea for the interns through a conversation with a naturalist in Petoskey who mentioned the 1978 study.

"It sounded like a project that students could do and which could give new information about our lakes. Before this work, there had been no estimate of the density and location of diporeia in our lakes,"Bretz said.

Diporeia are the most common of the deep dwelling macro-invertebrates, and the group found 12 examples of them in their studies. Mysis relicta (possum shrimp)are the next most common, but according to Bretz, mysis is a lot faster and escaped the interns' dredge all but one time in Elk Lake.

The group also found four examples of midge and mayfly larvae, and a few other critters that looked like small flatworms, but they couldn't identify.

The crew consisted of seven local students: Jesse Belanger and Brittany Miszkiewicz from Bellaire; Courtney Platte and Danielle Haydell from Central Lake; and Maggie Petersen, Andy Mach and Cameron Schaefer from Elk Rapids.

Every Tuesday morning, the group would head out onto Torch Lake, Lake Bellaire or Elk Lake. Once out, they lowered a Ponar dredge to the bottom of the lake to scoop up a chunk of sediment. They hauled it back to the boat and, with a fine screen, sifted through the marl to find the bigger bugs. The deepest sample they took was 120 feet.

They also used a plankton net to collect samples of bugs that live in the water itself.

One intern, Miszkiewicz, said it was always exciting to sift through and actually find one of the relicts. She also noted, when they began, the group had no idea the number they would find in their research.

"It was a really eye-opening experience,"Miszkiewicz said. "I didn't know what I wanted to do but I got into this internship and I found out." Miszkiewicz said she hopes to take biology classes in her first year at Alma College.

Hadley Robinson can be reached at hrobinson@ michigannewspapers.com or by calling 231-533-8523.