IMPRINT, the Bell Museum's quarterly magazine for members, offers stories of scientific adventure and discovery, insight into today's rapid environmental changes, updates on museum programs and exhibits, and fun activities for kids. IMPRINT is published quarterly and is available as a benefit of Bell Museum membership.

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by Jennifer Amie

Researcher Mary Balcer, an aquatic ecologist with the University of Wisconsin, patrols Lake Superior for pernicious invaders. Non-native species like the zebra mussel, a European import, can devastate the ecosystem’s fragile balance. For some time, scientists have believed that Lake Superior is inhospitable to the mussels, which can wreak havoc if they do take hold. On October 12, Balcer was about to test that premise—and 25,000 students witnessed her surprising discovery.

The chance to see science in action is just one of the benefits of the Bell Museum’s distance learning program Bell LIVE!, which launched a scientific expedition to Lake Superior this fall. Via live satellite broadcasts, students in 20 states watched Balcer’s experiment unfold.

Leaning over the side of her research vessel, the L.L. Smith Jr., Balcer tugged on a length of rope, raising an experimental contraption from the water. This white plastic cage, dubbed a "condominium," is home to a dozen zebra mussels. The device was deployed, fully occupied, one year ago to test whether live mussels could survive the habitat of Duluth harbor. "Because the open lake is so much colder than the harbor, and has a limited amount of algae, mussels may not do as well in the open waters," Balcer said. She believed, however, that the harbor’s environment might offer the mussels a fighting chance.

When Balcer hauled up her condo, she found not only living mussels within the chambers, but also dozens of young mussels covering the outside and clinging to the rope.

At the sight of the once pristine rope, now green, slimy, and covered with young mussels, Balcer gasped in astonishment–and students in classrooms across the country joined her. "This is very exciting!" she exclaimed.

From the size of the mussels (which were smaller than a kernel of popcorn) Balcer knew they had been born within the past one to five months. These young may have been produced by the caged mussels in the condo, or by other adults in the harbor. "The discovery of young mussels here, and elsewhere in the harbor, indicates that we will probably begin to see some clogging problems in the harbor in coming years," says Balcer. "I wouldn’t have expected that. That’s what’s so exciting about this job–you never know what you’re going to find next."

This sense of excitement is exactly what the producers of Bell LIVE! hope to convey to the students who are watching. "It’s important for students to see that science is a dynamic enterprise of experimentation,"says Carol Birtzer, the museum’s coordinator of distance learning. "By engaging students in scientific understanding, Bell LIVE! is helping to create a new generation of environmentally literate citizens."

The satellite broadcasts are the culmination of weeks of in-class preparation, during which middle school students studied the great lakes using a curriculum prepared by Bell Museum educators.

The broadcasts themselves are a complex production hosted by Dave Huddleston, WCCO-TV anchor, and KARE-11 meteorologist Belinda Jensen. These experienced on-air hosts have the daunting task of keeping three one-hour live shows on track–despite occasional mishaps such as a slippery fish escaping from a scientist’s grasp.

A group of nine students joined the hosts and researchers, participating in the experiments. Ninth-grader Colin Haverkamp, of Irondale High School in New Brighton, served as a fish wrangler, assisting Department of Natural Resources fisheries manager Don Schreiner. Haverkamp reached into tanks of live fish to display trout and sturgeon.

"Having kids on the air helps other kids know that they can actually do something when it comes to science," says Haverkamp. "I hope kids in the audience learn that science can be a lot of fun and that there’s more to it than just learning the metric system. In school, we don’t get to do a lot of hands-on stuff–you mostly learn from books. This is real because it’s actually out in nature."

One of those vessels, the Blue Heron, was originally built for commercial fishing on the Grand Banks. It was converted for research when the University of Minnesota’s Large Lakes Observatory acquired it in 1997 (for a video tour of the Blue Heron, visit http://www1.umn.edu/distancelearning/greatlakes/index.html).

Scientist Angela Cates demonstrated the Blue Heron’s CTD instrument, which is submerged in the lake to measure conductivity, temperature, and depth and to collect water samples. Cates uses the CTD to study recent changes in the temperature of Lake Superior. This may provide a better understanding of the gradual warming of the lake that has been demonstrated by 90 years of historical data.

Below deck, geophysicist and University of Minnesota associate professor Nigel Wattrus demonstrated sonar instruments used to study the lake floor, showing students images of a shipwreck and geological formations.

Minnesota Sea Grant scientist Doug Jensen broadcast from a much less glamorous location: the dark, spooky ballast of the retired ore ship William A. Irvin. Jensen demonstrated how exotic species are transported to the Great Lakes from faraway locations via ballast water.

One exotic invader found in Lake Superior is the sea lamprey, an ocean species whose blood-sucking habits earned it the nickname "vampire of the Great Lakes." The pale, eel-shaped lamprey attaches itself to a fish with its suction-cup mouth and row of rasping teeth, then feeds on the fish’s blood.

Only one in seven fish survives a lamprey attack, says Jensen. When students displayed a trout bearing a grisly lamprey wound, it was easy to see why. One sea lamprey can kill 40 pounds of fish during its adult phase, and the species has devastated lake trout populations in all the Great Lakes.

"It’s important for us to remember that aquatic nuisance species are an issue, so that we can be good environmental stewards," says Jensen.

Fortunately, successful control programs in Lake Superior have revived trout populations over the past 50 years while reducing the lamprey population to 90 percent of what it once was.

While the battle between native and exotic species formed a dramatic component of the Bell LIVE! program, the students and scientists also turned their attention to the subtler forms of life. Professor Bob Sterner, of the University of Minnesota’s Department of Ecology, Evolution, and Behavior, looked at Lake Superior from the point of view of its smallest inhabitants: the zooplankton.

Sterner asked students to imagine what it would be like to live as a tiny, sightless creature drifting in the vast, cold lake. Zooplankton are hairy, spiny, or filament-shaped creatures that may be the size of Abe Lincoln’s ear on the U.S. penny, or even smaller. Zooplankton drift across the lake, eating algae and, in turn, being eaten by fish. Sterner showed the tiny creatures under a microscope, and explained how they experience their world by sensing motion.

The lake’s small creatures can also be used by humans as pollution detectors, a function demonstrated by Environmental Protection Agency scientist Teresa Norberg-King. She places midges, aquatic worms, and tiny shrimp in water samples to test water quality. These sensitive animals are used to assess the toxicity of chemicals in the water. If the creatures die, stop reproducing, or fail to grow, then scientists can predict the toxic concentration of a chemical in the water.

Programs like Bell LIVE! help the EPA achieve its goal of raising environmental awareness, says Norberg-King. "I’m hoping that the kids in the audience will learn that we can make a difference. We know how to protect our environment, but everybody needs to pitch in–including them."

As the source of ten percent of the world’s fresh water, Lake Superior truly is an ecosystem that matters to everyone–no matter where they live. Next year, the Bell LIVE! program will visit Minnesota’s forests, helping kids across the country explore a new environment.