WELLFLEET, Mass. — Pockmarked muck blots this formerly lush marsh on Cape Cod, and a creek carves off eroded chunks along its edges. Dead plant roots jut from barren mud once covered with wavy mats of marsh hay.
New England scientists began noticing dead patches like this one near Lieutenant Island four years ago and call it sudden wetland dieback. Ecologists warn that saltwater marshes from Maine to Connecticut are suddenly and inexplicably dying, leaving behind land resembling honeycombs, Swiss cheese or an eroded desert landscape. Few scientists can explain it or recommend what to do. Even skeptics concede something unusual is happening.
"It's something that people who have spent their entire careers working in salt marshes have never seen before," said Stephen Smith, a plant ecologist who works in Cape Cod for the National Park Service. "There's no precedent for it."
Salt marshes are wetlands dominated by plant life sheltered from surf and capable of living where coastal waters fluctuate. Losing a marsh means eliminating a habitat for hundreds of fish, birds, shellfish and mammals and destroying a buffer capable of weakening a hurricane's destructive surge. Southern New England has lost between 50 to 70 percent of its saltwater marshes since white settlers arrived in the 17th century, according to one study. Marshes can migrate to keep up with changing sea levels, but modern development has caged them in. "There's nowhere for it go to go," Smith said. "So, if it's dying, we're kind of worried we may lose that habitat forever."
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