Abstract:
This survey was conducted as a partial repeat of previous introduced marine pest port surveys undertaken by Aquenal in Port Davey/Bathurst Channel in 2011 and 2003, with a particular focus on the Pacific oyster Magallana gigas following the detection of a live specimen in Schooner Cove in February 2022 that triggered an initial search by Natural Resources and Environment Tasmania (NRE Tas) in March 2022. However, no individuals were found, suggesting there had been no obvious recruitment or expansion of Magallana gigas within the estuarine system. This is despite extensive searching via targeted shoreline surveys by NRE Tas in March 2022 and this project (shoreline and immediate subtidal zone) in April 2022 and the broader pests survey in March 2023 that included more comprehensive subtidal diver-based searches. Shoreline searches showed that Carcinus meanas (European shore crab) now appears to be widespread and common within this system, following a similar pattern observed in eastern Tasmanian estuaries over the same period. However, unlike the moderate number of records in the 2002 survey, only one specimen of the introduced Metacarcinus novaezelandiae (Piecrust crab) was found, suggesting this species had not expanded its foothold in the region over this time. No other target macroalgal or macrofaunal introduced species were found, despite extensive searching of suitable habitats, including species such as Grateloupia turuturu, Undaria pinatiffida, Petrolisthes elongatus, and Maoricolpus roseus that are now common in south east Tasmanian waters.
Authors:
Neville Barrett, Graham J Edgar, Adam Davey, Elizabeth Oh, Ashlee Bastiaansen, Gustaaf Hallegraeff
Year:
2023
Journal:
Technical Report
Reference Type:
345
Volume:
Pages:
Attachment:
https://atrc.au/wp-content/uploads/2024/08/Protecting-Tasmanias-Port-Davey-Bathurst-Harbour-Marine-Pest-port-survey-2023-1.pdf
