Invasion
Invasion Description
1st Record: Perth/Western Australia/the lower Swan River and Hillarys Harbour (Smale and Childs 2011)
The presence of a single haplotype at many locations supports the hypothesis of introduced status in Western Australia (Dias et al. 2016; Dias et al. 2021).
Geographic Extent
Houtman Abrolhos Islands/Western Australia/Indian Ocean (2012-2015, Dias et al. 2016, 28º42?93?S, 113º49?17?E); Rottnest Island/Western Australia/Geordie Bay (2012-2015, Dias et al. 2016, 31º59?29?S, 115º31?23?E); Geraldton/Western Australia/Indian Ocean (2012, Bridgwood et al. 2014, Dias et al. 2016, -28.765555 , 114.61343); Fremantle/Western Australia/Indian Ocean (2012, Bridgwood et al. 2014, Dias et al. 2016, 32.050525 , 115.742816); Perth/Western Australia/the lower Swan River and Hillarys Harbour (Smale and Childs 2011; Dias et al. 2016), floats and seagrass beds; Busselton/Western Australia/Indian Ocean (2012, Bridgwood et al. 2014; 2012-2015, Dias et al. 2016, -33.635391 , 15.391397); 6 sites in the Perth area/Western Australia/Infian Ocean (Dias et al. 2021). Houtman Abrolhos Islands/Western Australia/Indian Ocean (Dias et al. 2021, 28S, 43W).; Gerladton/Western Australia/Indian Ocean (Dias et al. 2021)
Vectors
| Level | Vector |
|---|---|
| Probable | Hull Fouling |
Regional Impacts
| Ecological Impact | Habitat Change | |
| Didemnum perlucidum has been overgrowing blades of the seagrass Halophila ovalis in the Swan River estuary, Western Australia, decreasing seagrass cover. Density of the nonindigenous snail Batillaria australis has decreased in areas of grass beds colonized by D. perlucidum (Simpson et al. 2016). | ||
| Ecological Impact | Competition | |
| Didemnum perlucidum has been overgrowing blades of the seagrass Halophila ovalis in the Swan River estuary, Western Australia, decreasing the plant's rate of photosynthesis and growth. The tunicate has been spreading outward from areas of human infrastucture, such as docks and buoys (Simpson et al. 2016). | ||