Giant babies return to reef in major step for forest-scale kelp restoration

Baby giant kelps were planted across 7000 square metres of reef in southeast Tasmania last month, in the first attempt at ‘forest-scale’ kelp restoration in the Southern Hemisphere.

If successful, the unique restoration project will create an area resembling a natural giant kelp forest. It’s the result of over four years of dedicated research by the University of Tasmania’s Institute for Marine and Antarctic Studies (IMAS) marine ecologists, to investigate various methods and aspects of re-planting giant kelp.

IMAS researcher, Dr Cayne Layton, said the new project is making restoring larger areas of Tasmania’s giant kelp forests a reality.

“Our early efforts at IMAS built a really strong foundation for kelp restoration work. This project brings all that knowledge together and is moving our work to an exciting new phase,” he said.

Dive in to see giant baby kelp planting in action.

Giant kelp forests have declined by over 95% in Tasmania since the 1970s, driven by climate change and a strengthening East Australian Current that is driving warm, nutrient-poor water further south. Giant kelp losses impact biodiversity, reef productivity and industries such as tourism and fisheries.

Eaglehawk Dive Centre tourism operator, Mick Baron, has experienced first-hand the impacts of giant kelp loss to his business over recent decades.

“We had kelp to the north and to the south, so thick you couldn’t drive a boat through it. Within 20 years, it had all disappeared,” he said.

The Dive Centre is now working with scientists to help giant kelp recovery, while seaweed producer Sea Forest’s new state-of-the-art culturing facilities on Tasmania’s east coast have produced the juvenile kelps ready for out-planting on reefs.

“Until now, planting has focused on small patches and growing ‘just the trees’. This new collaborative project is the first time these methods have been applied at a forest scale,” said IMAS researcher, Dr Scott Bennett.

The rapid growth rates of giant kelp has accelerated interest in kelp forest restoration.

“Giant kelp forests are an exciting habitat for restoration,” said IMAS researcher, Dr Scott Ling.

“Unlike forests on land, which can take decades or centuries to restore, giant kelp grows so fast that we can potentially regrow a forest in a year.”

Fast facts

  • In 2012, giant kelp Macrocystis pyrifera became the first marine ecological community to be listed under the Environment Protection and Biodiversity Conservation Act 1999.
  • The need for urgent action is highlighted by the current Federal Senate Inquiry into the impacts of invasive Long-spined sea urchins (and the ‘urchin barrens’ they create), climate change and kelp loss in Eastern Australia.
  • Among the 39 submissions to the Inquiry, our UTAS | IMAS submission calls on the Federal Government to activate the Giant Kelp Forest Recovery Plan and provide $6 million funding for a Giant Kelp Forest Reforestation Strategy for this endangered ecological community.
  • This work aligns with the UN Decade on Ecosystem Restoration, which aims to prevent, halt and reverse the degradation of ecosystems on every continent and in every ocean.

Images and footage by Stefan Andrews | Ocean Imaging

Published 25 November 2022

Authorised by the Executive Director, Institute for Marine and Antarctic Studies
25 November, 2022