They’re hungry, hungry mollusks. Thousands of historic shipwrecks sunk in the American Great Lakes are at risk of being lost forever thanks to invasive, wood-destroying mussels. The lakes are home to an estimated 6,000 shipwrecks, with some dating back to the 17th century, according to estimates from the University of Buffalo. The Quagga mussel, originally native to the waters of Russia and Ukraine, is believed to have arrived in the Great Lakes in 1989 — possibly as a result of ballast dumps from transoceanic freighters traversing the lakes. The population of Quagga mussels has exploded in the waters of the...