Annex 11 - Code 11 - Marine Plants

  Performance outcomes                                  Acceptable outcomes   Response
  A condition of approval for any marine plant
  restoration is likely to require a post-works                               The substrates are designed and placed in areas that
  monitoring and maintenance program                                          are within the modern recruitment, growth and
  appropriate for the scale of the restoration works.                         survival envelope for natural rock oysters in the
                                                                              estuary, and supplement hard structure, of suitable
                                                                              design, which rock oyster ecosystems require as their
                                                                              foundation for establishment in the modern estuarine
                                                                              environment.

                                                                              Suitable hard structures need to be of a size,
                                                                              configuration, rugosity and heterogeneity, which
                                                                              support a diversity of species, while minimising
                                                                              sediment trapping, smothering of the substrate and
                                                                              maximising natural ecological processes. Such hard
                                                                              structures have been lost due to heavy modification of
                                                                              the Noosa River estuary and have resulted in the lack
                                                                              of reestablishment of rock oyster ecosystems in the
                                                                              estuary.

                                                                              Historically, oyster lease areas in the Noosa River
                                                                              estuary were dredged intensively for oysters in the
                                                                              early 1900’s, resulting in the removal of live oyster
                                                                              beds and the underlying bedrock. In 2016, Ecological
                                                                              Service Professionals (ESP) quantified the historic
                                                                              spatial extent of oyster beds in the Noosa River and
                                                                              concluded that it was likely to have been in the range
                                                                              of 41,530m2 to 207,650 m2, of which approximately
                                                                              16,850m2 of old oyster beds and oyster rubble remain
                                                                              buried by sediment in the historical oyster lease
                                                                              areas. This represents a massive loss of hard
                                                                              substrate in the estuarine system. For details see
                                                                              Section 1.3 of the Project Restoration Plan.

                                                                              The design of the restoration substrates (primarily
                                                                              rock and shell), and their configuration as oyster reef
                                                                              patches, as the basis for ecological restoration, also
                                                                              provides structured 3-dimensional habitat that is
                                                                              known to support diverse fish assemblages. The
                                                                              restoration substrates are designed to fit within the
                                                                              existing mosaic of available fish habitats and improve

State Development Assessment Provisions – version 2.6
State code 11: Removal, destruction or damage of marine plants                                               Page 11 of 24