Lake Superior's shipwrecks have largely been spared from invasive species but that won't last forever. Here's what researchers and divers have to say about how zebra and quagga mussels are impacting the area's underwater history.
The U.S. Fish and Wildlife Service and Big Canoe Creek Nature Preserve Director Doug Morrison reintroduced more than 100 endangered Canoe Creek Clubshell mussels (Pleurobema Athearni) and 100 Coosa Mocassinshell