2016-12-12 General Committee - Attachments 1, 2, 3 to Item 10 - Oyster Restoration Project

                                                             Ecological Service Professionals
                                                                                 Sustainable Science Solutions




   Figure 4    Dense oyster aggregation on intertidal mangroves in Moreton Bay

A variety of oyster species are likely to occur in the Noosa Estuary due to the warm waters
and proximity to tropical latitudes (the exact distribution of many oyster species in Australia is
currently unknown) (Nell 2001). Species known or likely to occur in the estuary include the
Sydney rock oyster (Saccostrea glomerata), milky oyster (Saccostrea cucullata), black lip
oyster (Saccostrea echinata), palmate oyster (Planostrea pestigris), leaf oyster (Isognomon
ephippium), and pearl oysters (Pinctata maculata) among others (Nell 2001; Thurstan 2015;
TNC & ESP 2015 and personal observations). A more detailed understanding of the
diversity of oyster species occurring in the Noosa Estuary will be a good scientific outcome of
the proposed restoration project, which would contribute to objective 4 of the Fish Habitat
Research & Management Program (DAF 2016).

Estimate of the Historical Extent of Oyster Banks in Noosa Estuary
It is estimated that the majority of oysters harvested historically from South East Queensland
came from intertidal and shallow banks, with approximately 20% coming from dredging of
subtidal reefs (Smith 1981). Oysters were collected intertidally or dredged from Noosa River
channel and shipped to areas in Pumicestone Passage and the Broadwater further south for
fattening prior to sending to market (Smith 1981). Traditionally, oyster cultivators in Moreton
Bay used a variety of readily available substrates including dead oyster shell, broken tiles
and sand to firm up the ground and increase the productivity of their beds (Smith 1981).
Based on historical reports of the quantity of oysters harvested from the Noosa Estuary in the
early 1900s (Marine Department Reports 1905; 1906 cited in Thurstan 2015), it is estimated
that between 2 and 3 million oysters were removed each year in 1905 and 1906 and that up
to 4000 bags annually (4 to 6 million oysters) were transported south from Noosa Estuary by
the Moreton Bay Oyster Company at the peak of the industry, until the 1930s. A historical
photo from 1908 of oysterman with bagged live oysters in Moreton Bay is provided to
illustrate the size of each bag used to transport oysters (Figure 6). Records of the actual size
of oyster harvested are limited, but conservatively, each live oyster was likely to be 5 cm long
when dredged and sent to Moreton Bay to grow to marketable size (oysters 5 cm in length
are considered too small in today’s commercial market and are returned to continue growing



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