Invasion
Invasion Description
1st Record: K; British Columbia/Okeover Inlet, Straits of Georgia (2003, USGS Woods Hole Science Center 2007).
Geographic Extent
Ketchikan/AK/Ketchikan Harbor (2022, Fouling plates, Ruiz et al. 2022); Edmonds Underwater Park, Edmonds/WA/Puget Sound (eradication attempted) (2004, USGS Woods Hole Science Center 2007; Bullard et al. 2007); Des Moines Marina/WA/Puget Sound (2004, USGS Woods Hole Science Center 2007); Taylor Shellfish Farms/WA/Gallagher Cove, 47 deg 08.38 min N lat, 122 deg 58.75 min W (2004, USGS Woods Hole Science Center 2007, Cordell et al. 2012); Pleasant Harbor/WA/Hood Canal (2010, Cordell et al. 2012); Vancouver Island/British Columbia/Lemmens Inlet (2005, USGS Woods Hole Science Center 2007); Campbell River, Vancouver Island/British Columbia/Straits of Georgia (2008, Choi et al. 2016); Jedediah Island/British Columbia/Sabine Channel, Straits of Georgia (2005, USGS Woods Hole Science Center 2007); Vancouver Island/British Columbia/Deep Bay Straits of Georgia (2005, USGS Woods Hole Science Center 2007); Nelson Island/British Columbia/Agamemnon Channel, Straits of Georgia 2004, USGS Woods Hole Science Center 2007; Bullard et al. 2007); Vancouver Island/British Columbia/Strait of Georgia (2008. Choi et al. 2016); British Columbia/Jervis Inlet, Straits of Georgia (2005, USGS Woods Hole Science Center 2007); British Columbia/Okeover Inlet, Straits of Georgia (2003, on mussel cages, USGS Woods Hole Science Center 2007); British Columbia/Trevenen Bay (2005, USGS Woods Hole Science Center 2007); Christy Island/British Columbia/Pendrell Sound (2004, USGS Woods Hole Science Center 2007); Sitka/AK/Whiting Harbor (6/13/2010, KFSK Petersburg, Alaska National Public Radio, 11/5/2010, Cohen et al. 2011, 57.0480556 -135.3694444, eradication is being studied, Chenoweth 9/24/2012; Ronco/9/26/2012)
Vectors
| Level | Vector |
|---|---|
| Alternate | Hull Fouling |
| Alternate | Fisheries Accidental (not Oyster) |
| Alternate | Oyster Accidental |
Regional Impacts
| Economic Impact | Fisheries | |
| Didemnum vexillum was found fouling shellfish cages and other aquaculture structures at Taylor Shellfish Farms, Quilcene, WA, and in Gallagher Cove, WA, Puget Sound and on oyster trays in Deep Bay, Baynes Sound, and mussel cages in Okeover Inlet, British Columbia (USGS Woods hole Science Center 2008). Switzer et al. (2011) tested chemical treatments (hydrated lime), mechanical treatments (manual scrubbing) and biological control (sea urchins. Strongylocentrotus droebachiensis, native) for cleaning fouled oysters. The mechanical and chemical treatments reduced fouling by Didemnum, but created free pace for botryllid tunicates to settle. | ||
| Ecological Impact | Habitat Change | |
| The introduced isopod Ianiropsis serricaudid occurred in high abundance with D. vexillum at Taylor Shellifish Frams, Puget Sound, but not found at other sites in the Sound (Cordell et al. 2012). | ||