1.Fashionable Fur from Louisiana's Wetlands
Louisiana's wetlands are infested with more than a million large, beady-eyed rodents called nutria. These natives of South America were brought to the U.S. in the 1930s to stock fur farms. Soon after, farm escapees and took up residence in Louisiana's bayous, among other places. High demand for fur kept the wild population more or less in check for a few decades. But when the fur market crashed in the 1980s, the nutria population exploded. Now, an artist named Cree McCree is trying to make nutria fur fashionable again to control wild populations and save Louisiana's marshes from nutria noshing.
Nutria are grazers. After their numbers climbed aerial surveys revealed large swaths of wetland that had been eaten bare. Native muskrats graze, too, but they like to nibble the tender leaves of marsh plants, whereas nutria prefer to feast on a plant's base and roots. "The plant dies, and it relinquishes its hold on the soil," says Michael Massimi, invasive species coordinator at Barataria–Terrebonne National Estuary Program (BTNEP), a group set up to protect wetlands affected by nutria.
Land managers have tried several strategies to get rid of the pests, including an unsuccessful state campaign in the late 1990s encouraging locals to eat the rodents (nutria jambalaya, anyone?). What has been more successful is a state program that pays trappers $5 for each nutria tail they deliver. The program brings in 300,000 to 350,000 tails each year. If trappers can sell the fur or meat, they can earn even more. But the bulk of these products go to waste because demand is so low.
So, in 2009 McCree decided to try and reestablish a market for the fur. With a grant from the BTNEP, she challenged local designers to create apparel featuring the rodent's fur. "We're not trying to promote fur so much as we're trying to utilize a wasted resource," Massimi says. The project—Righteous Fur—aims to market nutria fur as a "guilt-free" alternative to traditional fur. McCree has already held two fashion shows in New Orleans, and many of the pieces sold. Even the animal's enormous orange teeth have made it onto the runway as necklaces and earrings. "When they're attached to a nutria they're pretty hideous," Massimi says. "But when you mount them on some Balinese silver, they actually look quite nice."
2.Snuffing out Smelt in Northern Wisconsin
This giant disk of black rubber may seem harmless, but don't be fooled. This gizmo—called a GELI, short for Gradual Entrainment Lake Inverter—is designed to kill. It's the newest weapon in the war against invasive rainbow smelt, a native of the North Atlantic states.
Rainbow smelt were brought to the Midwest in 1912 as food for fish farm salmon. But the tiny fish soon escaped into Lake Michigan and then moved into Wisconsin's inland lakes, perhaps by hitchhiking in fishermen's bait buckets. In Wisconsin alone smelt have already invaded about 25 lakes, "and every year they tend to pop up in another lake," says Jake Vander Zanden, a biologist at the University of Wisconsin–Madison's (U.W.) Center for Limnology. Smelt compete with other species for food and feed on baby fish, including trout, walleye, yellow perch and cisco.
How will the GELI help to get rid of smelt? The goal, says Jordan Read, an environmental engineering graduate student at U.W.–Madison, is to "flip the lake on its head." Temperate lakes tend to stratify, with cold water sinking to the bottom and warm water floating on top. Smelt like the cold water. If the cold water disappears, so will the smelt—or at least that's the hope.
The researchers plan to test this idea out in Crystal Lake, an 84-acre lake in northern Wisconsin. In 2011 they will put about a dozen of these devices in the middle of the lake. Each disc has an inflatable tube running around the rim that is connected to an air compressor. Once the device has sunk to the bottom of the lake, the researchers can start the compressor, fill the tube, and the GELI will rise slowly to the surface, bringing up a large volume of cold water from the lake bottom. Once the GELI hits the surface, the tube will deflate and the GELI will sink again, bringing warm surface water to the bottom. "Eventually we erode that stratification," Read says.
The baby smelt don't mind warm water, so to wipe out the entire smelt population the researchers will have to mix the lake for several years. According to Vander Zanden and Read, the mixing shouldn't have an impact on native fish, which can tolerate warmer waters. The hope is that once the smelt are gone, native fish like yellow perch will rebound. "One of the big ideas here," Vander Zanden says, "is to test of whether the ecosystem can really be brought back to something resembling its original state after eliminating this nasty invasive."
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