Penrhyn Estuary holds great ecological importance as it includes saltmarsh, seagrass, mangroves, intertidal flats and it is frequented by migratory shorebirds. When the facilities at Port Botany were expanded there was a need to reclaim ~63 ha of Penrhyn Estuary. This and previous stressors led to a decline in seagrass area from 65,821 m2 in 2002 prior to construction works commencing, to 698 m2 in February 2007. Significant restoration and revegetation works were undertaken as part of the Port Botany Habitat Enhancement Plan, which has resulted in a doubling of saltmarsh area with higher than baseline biodiversity and condition. The seagrass restoration was less successful and the 6.5ha originally created is declining, potentially due to pre-existing stressors that exacerbated the original decline. See the Habitat Enhancement Plan and Post Construction Report linked below for detailed information on the methods, successes and lessons from the project.

Saltmarsh

Method: Planting, Rehabilitation

Rehabilitation - method: Restrict vehicle access, Weed control

Saltmarsh species: Suaeda australis, Sarcocornia quinqueflora, Sporobolus virginicus and Juncus kraussii

Planting density: S. quinqueflora and S. virginicus constitute 90% of the new area, with limited planting of the other two species.

Seagrass

Method: Planting, Weed control

Seagrass species: Posidonia australis (transplanted), Zostera capricorni and Halophila ovalis (allowed to colonise naturally)