First documented occurrence
Brian Coffey, December 2001. Reference: Coffey, B.T., 2001, Potentially invasive compound ascidian - Whangamata Harbour. Progress Report No. 1. Prepared for Waikato Regional Council, Hamilton.
First anecdotal occurrence
Merv Martin, Whangamata Harbour Master, Environment Waikato, October 2001
Didemnum vexillum Kott, 2002
Kott, P., 2002, A complex didemnid ascidian from Whangamata, New Zealand: Journal of Marine Biology Association of the United Kingdom, v. 82, no. 4, p. 625-628. [description of Didemnum vexillum] PDF format)
Kott, P., 2004, A new species of Didemnum (Ascidiacea, Tunicata) from the Atlantic coast of North America: Zootaxa, v. 732, p. 1-10. [description of Didemnum vestum and comparison with D. vexillum and D. lahillei] (PDF format)
Account of the appearance of Didemnum vexillum in New Zealand in 2001 and 2002
Coutts, A.D.M., 2002, A biosecurity investigation of a barge in the Marlborough Sounds: Cawthron Institute Report 744, 68 p. (PDF format)
This report includes information on the infestation of the Steel Mariner barge by D. vexillum; images of the species; location maps; a report by P. Mather (Kott) on the identification of the didemnid; a survey of the didemnid on the barge and its spread to the seabed beneath it; and the potential risks posed by the spread of the species.
Evaluation of methods for managing Didemnum vexillum in New Zealand.
Coutts, A., 2006, An evaluation of incursion response tools for invasive species: a case study of Didemnum vexillum in the Marlborough Sounds (New Zealand): Cawthron Institute Report 1093, 84 p. Prepared for Biosecurity New Zealand. (PDF format)
Web sites with imagery and text
New Zealand Diving and Salvage Limited; barge infestation and cleanup procedure; D. vexillum image on barge bottom. (PDF format)
New Zealand Diving and Salvage Limited (NZDS); barge infestation and cleanup procedure; same as report on the Cawthron website; (D. vexillum images; all are not identical to those in Cawthron Report No. 755). (PDF format)
Cawthron Report No. 755, barge infestation and cleanup procedure; (PDF format) ; same as report on NZDS website; (D. vexillum images; all are not identical to those in the NZDS report).
Web sites with text only
Cawthron News, 2001, barge infestation. (PDF format)
Cawthron News, 2002, barge infestation. (PDF format)
New Zealand regional map
New Zealand, South Island, Inset A
New Zealand, North Island, Insert B