Didemnum vexillum (Carpet Sea-squirt)

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First records in Great Britain of the invasive colonial ascidian Didemnum vexillum.  Kate Griffith, Stephen Mowat, Rohan H.F. Holt, Kirsten Ramsay, John D.D. Bishop, Gretchen Lambert and Stuart R. Jenkins (2002).

Didemnum vexillum – Feasibility of Eradication and/or Control in Holyhead Marina.  CCW Contract Science report No. 875 (2009).

The carpet sea squirt Didemnum vexillum: eradication from Holyhead Marina. Progress to October 2009. Rohan Holt, CCW

Survey of a non-native ascidian (sea squirt) Didemnum vexillum in Holyhead Harbour. CCW Marine Monitoring Report No (2009).

Assessment of the impacts of Didemnum vexillum and options for the management of the species in England.  Project report for Defra (2010).

Maps indicating potential spread of Didemnum vexillum in GB.  Developed with funding from Defra, CCW and SNH.  For information on methods refer to the above report ('Assessment of the impacts of Didemnum vexillum and options for the management of the species in England').

Recommendations for Reducing the Rate of Spread and Potential Re-Invasion of Didemnum vexillum.  Report of the GB Working Group for D. vexillum (2011)

Initial response to the invasive carpet sea squirt, Didemnum vexillum, in Scotland.  Commissioned Report No. 413 (2011).

Eradication of the non-native carpet ascidian (sea squirt) Didemnum vexillum in Holyhead Harbour: Progress, methods and results to spring 2011  Rohan Holt and Ashley Cordingley (2011).  CCW Marine Monitoring Report No. 90

Denny, C. M. (2008) Development of a method to reduce the spread of the ascidian Didemnum vexillum with aquaculture transfers. – ICES Journal of Marine Science, 65: 805–810.

Switzer, S.E., Therriault, T.W., Dunham, A. & Pearce, C.M. (2011) Assessing potential control options for the invasive tunicate Didemnum vexillum in shellfish aquaculture. Aquaculture, 318: 145-153

Rolheiser, K.C., Dunham, A., Switzer, S.E., Pearce, C.M. & Therriault, T.W. (2012) Assessment of chemical treatments for controlling Didemnum vexillum, other biofouling, and predatory sea stars in Pacific oyster aquaculture. Aquaculture, 364-365: 53-60

Invasive Species Compendium: Didemnum vexillum - CABI website (11 March 2014)

Coutts, A.D.M. & Forrest, B.M. (2007) Development and application of tools for incursion response: Lessons learned from the management of the fouling pest Didemnum vexillum. Journal of Experimental Marine Biology and Ecology 342(1): 154-162

Nimmo, F., Cook, E. J., Moxey, A. P., Hambrey, J. and Black, K. (2011) Cost benefit analysis of management options for Didemnum vexillum (carpet sea squirt) in Scotland. Report by Hambrey Consulting in association with the Scottish Association for Marine Science and Poseidon Aquatic Resource Management to the Scottish Government Tender Ref: Cr/2011/16

Carman, M.R., Allen, H.M. & Tyrrell, M.C. (2009) Limited value of the common periwinkle snail Littorina littorea as a biological control for the invasive tunicate Didemnum vexillum. Aquatic Invasions, 4(1): 291-294

McCann, L.D., Holzer, K.K., Davidson, I.C., Ashton, G.V., Chapman, M.D. & Ruiz, G.M. (2013) Promoting invasive species control and eradication in the sea: Options for managing the tunicate invader Didemnum vexillum in Sitka, Alaska. Marine Pollution Bulletin, 77(1-2): 165-171



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