There’s a parasite inhabiting the bodies of crabs and making them infertile. Amy Fowler says that if that parasite entered the Chesapeake Bay, 90% of our crabs would be inedible. America is littered with battlefields, and abandoned forts. They’re often some of the most pristine sites of Virginia ecosystems. Plus: Todd Lookingbill is a SCHEV winner for his research on the ecological value of battlefields.

Later in the show: Scientists first noticed coral reefs disappearing in the late nineties. Now, it’s getting worse as underwater temperatures continue to rise. Researchers Nastassja Lewinski and Liza Rogers are busy testing and developing solutions to coral bleaching. And: Deer enjoy forest edges. They’re away from the predators in the heart of the forest, and there’s less competition for food. But Matthias Leiu says that the lone star ticks love the forest edge, too.