2022-02-08 Planning and Environment Committee Meeting Agenda

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA   8 FEBRUARY 2022




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PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                                         8 FEBRUARY 2022

           In 2006, Dr Julie Phillips (macroalgal expert and part of the previous consortium of scientists)
           published an article in the Marine Pollution Bulletin titled: Drifting blooms of fhe endemic filamentous
           brown alga Hincksia sordida af Noose on fhe subtropical east Australia Coast.
           Herein Phillips suggested an alternative view to previous observations that the bloom formed
           offshore of Fraser Island and hypothesized that due to the alga’s biology and ecology, the Noosa
           River estuarine system / Laguna Bay was the more probable source of Hincksia sordida and the
           nutrient inputs into this system must be substantial to generate the high bloam biomass.
           Phillips suggested at certain times of the year the ‘attached’ Hincksia sordida releases filaments
           (thalli) into the waterways and out into Laguna Bay. Also, that bloom formation precedes the
           appearance of the ‘drifting’ bloom by at least one to two months, with the species growing rapidly
           aver winter. The to essential knowledge gaps highlighted by Phillips, to inform future management
           included:
               e = Identification of source populations of Hincksia sordida in the Noosa Estuary,
               e   Identifications of nutrient inputs from groundwater and surface flows (Phillips, 2006).

                        ~Ource populations
                            Via lldle eis,
                                                        Accurate                 Informed
                                +            —»        ecological     ===)    =~Management
                                                       knowledge                 Strategy
                        Origin of nutrients
                         rueiling  Di ‘a

           However, Noosa did not experience further blooms of Hineksia sordida in Laguna Bay for the next
           11 years, until September 2017.
           After such a lag time the bloom was unexpected and caused removal of just under 1,000 tonnes of
           decomposing algae and sand from Main Beach over the 2017-18 spring / summer season.
           Prompted by past experiences, Council established an internal working group to manage the
           immediate effects of large deposits of algae on Main Beach, while also investigating various
           strategies to mitigate impacts of future blooms on the community, environment and economy.
           To this end, Council hosted a workshop with a panel of experts In January 2018 to review past
           studies and identify key actions to build a greater understanding in-house of Hincksia sordida, and
           a means to possibly identify the origin of nutrients fueling blooms
           The workshop outputs (refer Table 1) triqged development of the Noosa River Algae Monitoring
           Project as a crucial first step to help identify if source populations of Hincksia sordida (and other
           potentially bloom-forming macroalgal) exist locally.

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