The Tasmanian salmonid industry is planning for a significant expansion of salmon aquaculture in Macquarie Harbour. This will result in an increase in nutrients – nitrogen and phosphorous – from salmon farming waste products into the environment. These nutrients may result in increased primary production – of micro and macro-algae, although the extent of increased production and the potential for eutrophication of the system is not fully understood The issue of macroalgal growth has been raised by community stakeholders and in light of recent comments the Tasmanian salmonid industry wishes to support baseline research investigations and monitoring. These macroalgae are largely intertidal and therefore obvious to the community, which provides an opportunity to involve community members in the macroalgal assessments.
There is a pressing need to commence baseline monitoring of macroalgal distribution and abundance in Macquarie Harbour before additional salmon farming commences. As different species of macroalgae occur at different times of the year, autumn and spring monitoring will be necessary.