Fragment reattachment, reproductive status, and health indicators of the invasive colonial tunicate Didemnum vexillum with implications for dispersal
MetadataShow full item record
The invasive colonial tunicate Didemnum vexillum is now widespread in coastal and offshore waters of New England, USA. D. vexillum can inflict ecological and economic damage through biofouling and habitat modification. Natural and anthropogenic processes that fragment colonies of D. vexillum may be accelerating the spread of this invader. Reattachment success and fragment viability were confirmed in the laboratory after four weeks of suspension in experimental aquaria. The shape of suspended D. vexillum fragments progressed from flattened to globular spheres and then flattened again after reattachment to the substrate. Reproductive activity, confirmed by the presence of eggs and larvae, was observed for fragments suspended up to three weeks suggesting that D. vexillum is capable of reproducing while in a fragmented, suspended state. An index of colony health was used to monitor change in D. vexillum health while in suspension. Overall, colony health declined with time in suspension although colonies that appeared dead (black and gray in overall color) still contained a substantial number of healthy live zooids. These results suggest that activities that cause fragmentation can significantly facilitate the spread of D. vexillum. Coastal managers should consider reducing or eliminating, when practical, activities that return fragmented colonies of D. vexillum to the water. In-water cleaning of biofouling and dredging are likely expediting the spread of this invasive species unless biofouling can be contained and removed from the water.
This manuscript is not subject to U.S. copyright. The definitive version was published in Biological Invasions 14 (2012): 2133-2140, doi:10.1007/s10530-012-0219-8.
Showing items related by title, author, creator and subject.
Coldwater reattachment of colonial tunicate Didemnum vexillum fragments to natural (eelgrass) and artificial (plastic) substrates in New England Carman, Mary R.; Grunden, David W.; Ewart, Danielle (Regional Euro-Asian Biological Invasions Centre (REABIC), 2014-03)The colonial tunicate Didemnum vexillum Kott, 2002, was introduced to New England in the 1980s and by 2000 it was widespread. This highly invasive species spreads by larval release and fragmentation. We tested the ability ...
The colonial ascidian Didemnum sp. A: Current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America Bullard, Stephan G.; Lambert, Gretchen; Carman, Mary R.; Byrnes, J.; Whitlatch, R. B.; Ruiz, G.; Miller, R. J.; Harris, L.; Valentine, Page C.; Collie, Jeremy S.; Pederson, J.; McNaught, D. C.; Cohen, A. N.; Asch, Rebecca G.; Dijkstra, Jennifer A.; Heinonen, K. (2006-10-09)Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the ...
Sutherland, Kelly R.; Madin, Laurence P.; Stocker, Roman (2010-07)Salps are common in oceanic waters and have higher per individual filtration rates than any other zooplankton filter feeder. Though salps are centimeters in length, feeding via particle capture occurs on a fine, mucous ...