Report on Port of Botany Bay Introduced Marine Pest Species Survey
|Full report - Report on Port of Botany BayIntroduced Marine Pest Species Survey
The Port of Botany Bay is located about 15 kilometres to the south of the Sydney central business district, on the central coast of New South Wales, at around 34º 00' S, 151º 14' E. The associated catchment of the bay is around 1100 km2, and includes the drainages of the Georges, Woronora and Cooks Rivers. The principal trade of the port is in container goods, chemicals and petroleum and petroleum products.
A survey for introduced marine species was carried out in the port area and around the adjacent bay coastline between 19 - 29 October 1998. This survey focused on habitats that were likely to be colonised by such introduced species and generally followed the sampling protocols developed for the National Australian Ports Surveys by the CSIRO's Centre for Research on Introduced Marine Pests (CRIMP).
Previous known introductions to Botany Bay have included four species of crustaceans, three mollusc species, several species of worms, toxic dinoflagellates, three species of gobies and the Japanese sea bass.
The toxic dinoflagellate Alexandrium sp. was the only Australian Ballast Water Management Advisory Council (ABWMAC) target introduced pest species collected during the present survey. This dinoflagellate, which generally occurs encysted in the bottom sediments, has been commonly recorded from a number of coastal bays and estuaries, mainly ports, in south-eastern Australia. Blooms of such dinoflagellates in the water column produce neurotoxins, which can not only cause fish kills, but can also accumulate in shellfish and, being toxic to humans, may therefore affect oyster growing and other aquaculture industries. These cysts, however, were not found to be abundant in Botany Bay, and no toxic dinoflagellate blooms have previously been recorded there.
A number (34) of other introduced (18) and cryptogenic (i.e. of unknown origin) (15) species were also recorded from the bay during the present survey, in addition to the other dozen or so such species previously recorded there. These introduced species are recognised as having been transferred to Australia in both historic and modern times, most probably via ships' ballast water discharge and/or hull fouling, but are not listed as "pest species" posing any significant economic or environmental threats in this area. The additional introduced species found included 2 species of polychaetes (Boccardia chilensis and Capitella capitata), 4 species of crustaceans (Corophium ascherusicum, Corophium acutum, Paracerceis sculpta and Megabalanus rosa), 12 species of bryozoans (Amathia distans, Bowerbankia sp., Zoobotryon verticillatum, Conopeum seurati, Bugula dentata, Bugula flabellata, Bugula neritina, Bugula stolonifera, Cryptosula pallasiana, Schizoporella unicornis, Tricellaria occidentalis and Watersipora subtorquata.), and 1 ascidian (Botrylloides leachi). The cryptogenic species included 2 species of algae (Caulerpa filiformis and Pterosiphonia bipinnata), 4 hydrozoans (Clytia hemisphaerica, Obelia dichotoma, Phialella quadrata and Antenella secundaria), 1 anthozoan (Culicia c.f. tenella), 6 species of crustaceans (Megabalanus tintinnabulum, Megabalanus zebra, Caprella equilibra, Paracorophium excavatum, Pseudosphaeroma campbellense and Palaemonella rotumana), and 2 species of bryozoans (Electra tenella and Fenestrulina sp.).
Overall, and apart from the single toxic dinoflagellate species (Alexandrium sp.) identified, from the results of this survey Botany Bay would appear to be otherwise free of ABWMAC listed target introduced marine pest species. In the light of the above, it is recommended that Alexandrium be periodically monitored in both the water column and sediments of the bay.
The data collected during this survey fit the requirements of the Department of Agriculture and Water Resources Decision Support System in relation to the need or otherwise for any future ballast water controls on shipping using this port.