6. Noosa River DMP Ver0 (Combined)

4 Marine Plants
Marine plants are protected against deliberate damage or destruction under the Fisheries Act
1994 (Part 6, Section 123) as they provide valuable fish habitat. Marine plants provide important
habitat for fish including the provision of shelter, food and nursery areas for juvenile fish species.

The definition of a marine plant is broad and includes plants or plant material of tidal origin or
other plants on tidal land. Marine plants include mangroves, seagrass, samphires, saltcouch
and saltmarsh plants, algae and other tidal plants growing adjacent to the tidal zone, landward
and seaward. Material of a tidal plant relates to bark, leaves, stems, roots, flowers or seeds.

Appendix 1 of the Management and Protection of Marine Plants and other Tidal Fish Habitats,
Fish Habitat Management Operational Policy FHMOP 001 (2007) provides a list of Queensland
marine plant species.

An assessment was undertaken to identify the location/s of any marine plants within or in
proximal to the nourishment and extraction areas. The methods used and the results of this
assessment are presented in the following sections.

4.1 Foreshore Survey
The marine plants along the foreshores of all the subject sites were identified. Details of location,
species, girth and height for each plant was recorded and are presented in Appendix A.

Two Avicennia marina (Grey Mangrove) were recorded in the intertidal zone of the
replenishment area along Gympie Terrace. Seedling mangroves and one established A. marina
were recorded at the interface of the existing and proposed new extraction areas at Hilton
Esplanade.
Mangroves can occur from sea level to the elevation of the highest neap tides along low-energy
coastlines. In riverine ecosystems, mangroves are important for trapping sediments and for
nutrient retention.

An additional species, Casuarina glauca (Swamp She-oak) was also recorded on the Gympie
Terrace and Hilton Esplanade foreshores. This species is not listed in Appendix 1 of the FHMOP
001. However, where C. glauca occur adjacent to tidal land they fall within the definition of a
marine plant.

No marine plants were recorded at Munna Park.

4.2 Seagrass Survey
Seagrasses are a widespread and important marine plant, providing carbon sequestration in
underlying sediments, shoreline stabilisation, nutrient and sediment capture, fish habitat, and
foraging habitat for dugongs and turtles (Orth et al., 2006). Seagrass habitat is vulnerable to
human disturbance (Connelly et al., 2015).

The proposed new extraction zone was surveyed for seagrass using an underwater drone
capturing video footage. Using an underwater drone was considered safer alternative to divers
given the level of boating and tidal currents.

Randomly located transects were surveyed using the drone to provide overall assessment of
seagrass presence/absence throughout the proposed extraction area.

Noosa River                                                                                   Page 7
Marine Plant Impact Assessment
Project Number: BC-20067