ONE of the most important species of seaweed along the NSW Coast has mysteriously disappeared from Sydney’s coastline.
The missing sea forest, crayweed, disappeared 30 years ago from the city’s reef along with its associated sealife – abalone and crayfish.
But at Little Bay, Malabar and Bare Island, a team of University of NSW scientists have replanted the lost ocean trees to bring life back to our underwater “rocky deserts”.
Dr Ziggy Marzinelli and Dr Alexandra Campbell planted crayweed five years ago on small 5sq m patches at Long Bay and now it has reproduced more than 200sq m.
“Seaweed is like the trees of the ocean. Just like bringing trees into an area of land attracts birds and mammals, our aim is to restore the marine biodiversity in Sydney by providing a habitat and food supply,” Dr Campbell said.
They believe the seaweed was killed off between Palm beach and Cronulla by sewage pollution in the 1980s. But with improved water quality, the seaweed now thrives underwater.
“Everyone in Sydney loves going to the beach and enjoys the water but they may not realise that key things that define these reefs and beaches are starting to decline or disappear,” Dr Marzinelli said. “When you bring this seaweed back you also bring back all of the animals and biodiversity associated with it.”
Dr Marzinelli said along the NSW coastline, crayweed was one of two important habitat-forming species.
“Without it the oceans look like a rocky desert – extensive patches of bare rock, that’s all you would see,” he said.
“When you get this underwater forest, you see lots of different species, which is good for fishermen, divers and the marine system.”
The crowdsourcing campaign, Operation Crayweed – set up with Dr Adriana Verges – has raised $32,000 to help restore the underwater forests. They team is calling on dive clubs to sponsor one of 25 proposed sites – including Maroubra, Coogee and Clovelly – to breathe life back into the sea.
Visit operationcrayweed.com to donate before the end of January.