Invasion
Invasion Description
1st record: Sandwich/MA/Eastern end of Cape Cod Canal (1981, R. Whittaker to JTC,. personal communication, 1984)
Geographic Extent
Brier Island/Nova Scotia/Gulf of Maine (8/2017, Ma et al. 2018, 44.2586, –66.3367, established); St. Andrews area/New Brunswick/Passamaquoddy Bay (2018. Ma et al. 2018); Brewer South Marina, Freeport/ME/Casco Bay (2003, MIT Sea Grant 2007); Cape Elizabeth/ME/Dyers Cove, Casco Bay (2010, Massachusetts Office of Coastal Zone Management 2013); Wells Harbor Marina/ME/Wells Harbor (2013, Wells et al. 2014); Isles of Shoals/NH/Gulf of Maine (1993, Dijkstra et al. 2007); Portsmouth/NH/Great Bay (1997; Blezard 1999); NH/Great Bay (2002, Ruiz et al., unpublished data); Wentworth Marina, Portsmouth/HN/Great Bay (2006, Harris and Dijkstra 2008); Coastal Marine Lab, Portsmouth/NH/Great Bay (2006, Harris and Dijkstra 2008); Rockport/MA/Folly Cove (2006, MIT Sea Grant 2011); Jodrey State Pier, Gloucester/MA/Gloucester Harbor (2010, Massachusetts Office of Coastal Zone Management 2013); Hawthorne Cove Marina, Salem/MA/Salem Harbor (2000, MIT Sea Grant 2007; 2010, Massachusetts Office of Coastal Zone Management 2013); Seaport Landing Marina, Lynn/MA/Lynn Harbor (2002, Agius et al. 2007); Winter Island/Salem/MA/Salem Harbor (2008, MIT Sea Grant 20011); Rowes Wharf, Boston/MA/Boston Harbor (2013, Wells et al. 2014); Green Harbor Marina, Marshfield/ME/Cape Cod Bay (2013, Wells et al. 2014);; Sandwich/MA/Eastern end of Cape Cod Canal (1981, R. Whittaker to JTC,. personal communication, 1984); Sandwich Marina/MA/Cape Cod Bay (2000, MIT Sea Grant 2007)
Vectors
| Level | Vector |
|---|---|
| Probable | Hull Fouling |
Regional Impacts
| Ecological Impact | Competition | |
| In experiments in Lynn Harbor, Massachusetts Bay, Diplosoma listerianum achieved a stand-off with Botrylloides violaceus, becoming co-dominant, covering ~37% of the plates at the peak of its growth (Agius 2007). | ||
| Ecological Impact | Food/Prey | |
| Increasing abundance of the introduced colonial tunicates Didemnum vexillum and Diplosoma listerianum has resulted in population growth of the native Bloodstar starfish Henricia sanguinolenta (Dijkstra et al. 2012). | ||
| Ecological Impact | Trophic Cascade | |
| Increased abundance of the Bloodstar starfish (Henricia sanguinolenta), supported by growing populations of Didemnum vexillum and Diplosoma listerianum, has resulted in increased predation and near-disappearance of the cryptogenic sponge Halichondria panicea (Dijkstra et al. 2012). | ||