Smithsonian NEMESIS Database Tracks Rock Vomit and Other Marine Invaders
Posted on March 13, 2012
The Smithsonian Environmental Research Center has created NEMESIS (National Estuarine and Marine Exotic Species Information System), an online public database to provide information about invasive, non-native marine species throughout the nation. NEMESIS launched March 5 with tunicates, a group that includes the destructive rock vomit (pictured above). Tunicates, also known as ascidians or sea squirts, are filter feeders that grow on hard surfaces.
The tunicate Didemnum vexillum (commonly known as D. vex or "rock vomit") has created serious problems on both coasts of the United States. It was discovered in Sitka, Alaska, during a citizen science survey called the Bioblitz in June 2010. The mat-like species grows rapidly and can completely cover aquaculture nets, shellfish beds and sensitive marine environments.
The Smithsonian says mitten crabs, zebra mussels, rock vomit and hundreds of other non-native species have invaded coastal regions throughout the United States. They often causing dramatic changes to coastal ecosystems and significant economic costs. The Smithsonian says no part of the country is untouched by these non-native species.