2015-11-10 - P&O Agenda - Item 7, Attach 2 - Assessment of Oyster Recruitment

degree of sedimentation, associated with runoff and re-suspension of fine sediments early in
summer, created conditions that were unsuitable for recruitment of S. glomerata (as
discussed by Diggles 2013). Furthermore, this assessment provided a spatially and
temporally restricted assessment of the potential for recruitment of oysters (i.e. over 5
months), so the lack of S. glomerata does not preclude settlement and recruitment on
restored reefs, which could occur at different times in the year or in different locations of the
estuary. An encouraging sign for any reef restoration program, with the objective to enhance
biodiversity and fisheries productivity, was the recruitment of numerous other species
including non-commercial oyster species, barnacles and mussels on the settlement tiles and
associated deployment structures. These types of sessile species provide an important
component of the overall biodiversity of estuarine systems and are likely to contribute to food
webs and provide a filtration function similar to that of commercial oyster species. The
oysters that recruited to the tiles would also be suitable for collection for bait by recreational
fishers and provide structural habitat and a food source for commercially and recreationally
important fisheries species.




    Figure 14. Growth of S. glomerata on a jetty in the lower Noosa Estuary

Subtidal reefs in the Sunshine Coast have a diverse benthic assemblage of corals,
macroalgae, barnacles, ascidians, sponges and bryozoans (Hooper & Kennedy 2002;
Walker & Schlacher 2014). There is also a diverse fish fauna that associate with both natural
and artificial reefs including, with more than 192 species known to associate with these
structures (Schlacher-Hoenlinger et al. 2009). Reintroducing oyster reefs into this shallow


Restoration of Noosa Estuary: An Assessment of Oyster Recruitment                                17