Maryland's population is 50,000 and growing rapidly. The Blackwater is the epicenter of the boom, but nutria now infest the entire Eastern Shore. He gestures with his cigarette at a ragged stretch of half-eaten Blackwater salt marsh over the bow. They are devastating habitat for rare native species like bald eagles and eliminating nurseries for the crabs and oysters that have paid the mortgages of tidewater families for generations. Nutria scatter into the heart of a wetland, and randomly chew into its thick carpet of starchy roots.
Aerial photos show the marsh damage blistering until the eat-outs merge into open bays.
Then saltier water from the Chesapeake seeps in with the tide, strangling stands of loblolly pine and accelerating erosion. To these researchers, the only question is how best to kill nutria. One agency posts Cajun recipes on its Internet site. A sheriff's SWAT team blasts the rodents for nocturnal target practice. But the nutria are growing cagey.