Mangrove and saltmarsh flats extended across the estuary of the Cooks River and Sheas Creek.

This was a swampy area with brackish or slightly salty conditions occurring back from the estuary, which received freshwater drainage and occasional river flooding. The saltmarsh would have provided reeds, which could be used for weaving net bags.

Shellfish including mud oysters may also have been taken from these areas. Water birds such as Brolga may have also used this area.