Bennetts seaweed

Bennetts Seaweed. Photo: Alan Millar

Scientific name

Vanvoorstia bennettiana

Status in NSW

Presumed extinct.


A marine red algal species which consists of a flat, finely meshed blade.

Species similar in appearance

Vanvoorstia (Vanvoorstia spectabilis and Vanvoorstia coccinea).


About the size of an out-stretched hand.


Bennetts Seaweed has only ever been collected from two localities in Port Jackson, Sydney Harbour.

Why did the Bennetts Seaweed go extinct?

There is limited information on the ecology of this species, but it is assumed that it was highly sensitive to environmental change. Bennetts Seaweed probably suffered severe population decline as a result of human activities including shipping traffic, dredging and urban run-off, all of which result in heavy siltation. Heavy siltation can clog the fine netted structure of the seaweed blades, blocking essential light needed for photosynthesis.

More information