Towra Point Nature Reserve is an extensive area of estuarine mangrove and saltmarsh on the southern side of Botany Bay, to the north of Captain Cook Drive.
There are two mangrove species in the reserve. Grey Mangrove, Avicennia marina, is the more common species, easily recognised by its aerial roots (pneumatophores) and pointed leaves. River Mangrove, Aegiceras corniculatum, has rounded leaves and no pneumatophores. The mangrove forests in the reserve represent about half of those remaining in the Sydney region.
Saltmarshes are dominated by salt-tolerant plants, particularly Sarcocornia quinqueflora, that are adapted to occasional inundation by high tides. The 157 hectares of saltmarsh at Towra Point are the biggest saltmarsh habitat in the Sydney region.
Towra Point contains a few small pockets of littoral rainforest growing on sheltered sites within the estuarine vegetation, now listed as an Endangered Ecological Community: Sutherland Shire littoral rainforest. Rainforest trees include Tuckeroo, Cupaniopsis anacardioides, and the threatened species Magenta Lilly Pilly, Syzygium paniculatum.
They found also "several trees which bore fruit of the Jambosa kind, much in colour and shape resembling cherries", writes Banks of presumably the Magenta Lilly Pilly, Syzygium paniculatum, which was brought back by Solander after the excursion to the Head of the Bay. Presumably this had not been seen at the Kurnell landing place although it still grows in the Towra Point part of Botany Bay.
No specimen of Casuarina glauca, Swamp Oak, was collected at Botany Bay in 1770 but Cook described two sorts of timber tree growing there. One, 'that grows tall and strait some thing like Pines, the wood of this is hard and Ponderous and something of the nature of American live oaks', is evidently Casuarina glauca. It would have been common along the foreshores, and in low-lying estuarine areas, and is still common around Towra Point today.
Towra Point Nature Reserve was listed as a Ramsar site in 1984, that is, a wetland of national and international importance to migratory birds. The site hosts 31 of the 66 species presently listed in the Japan-Australia Migratory Birds Agreement, as well as species listed in the China-Australia Migratory Birds Agreement. Several other bird species listed as threatened or endangered in NSW are also found here.