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

           6.     Future Directions

           6.1.   Continued Monitoring
           Continuing the monitoring program into the future would greatly enhance Council’s understanding of
           algae behavior in the river over time. This will enable management actions to be established to not
           only understand the nature of algae behavior and species composition over time, but hopefully
           identify reasons for changes in algae composition and behavior to inform management actions.

           At this stage the relationship between nutrients and algal growth in the river is inconclusive. Trace
           modelling of nutrients in the river to further understand where potential nutrient sources are coming
           from and where they end up would be particualry useful and may also help identify potential nutrient
           sinks.

           It must be noted that Hincksia sordida is not the only culprit of potential estuarine and marine
           phytoplankton blooms with the closely related filamentous brown algae Ectocarpus siliculosus and
           Hincksia mitchelliae also having been found growing in the river and on the groynes of Main Beach.

           Laguna Bay is not the only place on the east coast of Australia where Hincksia sordida blooms have
           occurred. A study conducted by Elgin Associates Pty Ltd on behalf of NSVV EPA and Bega Valley
           Shire Council, also found Hincksia sordida to be the problem bloom species in Merimbula Bay on
           the South Coast of NSW from 2008-2012. The bloom caused similar problems at Merimbula as in
           Noosa and occurred at the same time of year.

           6.2    Nutrient monitoring and modelling in the river
           As outlined in the actionns from the Hincksia sordida workshop in January 2018, nutrient modelling
           in the river and Laguna Bay remains an outstanding action and would be a key tool to help not only
           to identify sources and transport of nutrients that trigger bloom situations

           7.     Acknowledgements
              e   Dr Julie Phillips (Eco Algae Research Pty Ltd)
              e   Lindsay Hunt (JarvisHunt Consultancy Pty Ltd)

           8.     References

           Draft The Noosa River Plan (2018) Noosa Council.
           Dobson, M & Frid, C (1998) Ecology of Aquatic Systems. Prentice Hall England
           Phillips, J.A. (2006) Drifting blooms of the endemic filamentous brown alga Hincks/a sordida at
           noosa on the subtropical east Australian coast. Marine Pollution Bulletin 52 962-968
           Eco Algae Research Pty Ltd Report on the macroalgae from Noosa Waters collected on the 22"¢
           August 2018

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