Alaska has a near-pristine marine ecosystem—it has fewer invasive species in its waters than almost any other state in the U.S. But that could be changing. With help from local volunteers, biologists at the Smithsonian Environmental Research Center (SERC) and Temple University have reported a new invasive species in the Ketchikan region, the invertebrate filter-feeder Bugula neritina, and documented the continuing spread of three other non-native species.