Concern has been growing about seagrass diminishing for many decades throughout many parts of the world, including Fleurieu coastlines. 

Long strands of green ocean plant life, seagrass, or seaweed as it’s often known, is a vital element of marine ecosystems.

Underwater seagrass meadows protect shorelines from erosion and storms by stabilising sand, improving water quality by reducing nutrients and turbidity. 

Seagrasses can store more carbon than rainforests and provide important foraging and nursery grounds for recreational and commercial fish species including baby pink snapper, whiting, blue swimmer crabs, prawns, King George whiting, garfish and squid. 

They are also critical habitat for many other fish and invertebrate species including the region’s iconic leafy and weedy seadragons.

Seagrass decline is caused by pollution, stormwater discharge and development adjoining coastal areas, as well as rising sea temperatures and storm surges.

To help mitigate and reverse these losses, Landscapes Hills and Fleurieu and local partners are supporting OzFish Unlimited’s national seagrass restoration program, Seeds for Snapper.

It’s the second summer of action on the Fleurieu, where local volunteers comb the beaches and near shore waters for seagrass fruit. 

Fishers are also welcome to participate and collect the floating fruit from marine currents along the coast. 

Collected fruit (that carry and protect a single seed) will be stored in holding tanks, before being propagated into sandbags and returned to the sea floor of Encounter Bay, aiming to reproduce and create boundless underwater meadows of seagrass. 

The method is a scientifically proven method of seagrass restoration following successful programs in metro waters.

Tape weed (or Poisidonia spp.) seagrass fruits are released between mid-December to January by local seagrass populations that form slicks on the surface of the water and drift ashore on incoming tides.

Caroline Taylor, Landscapes Hills and Fleurieu Coast and Marine Project Officer, says many volunteers helped with seagrass fruit collection last year, deploying 150 sandbags (with almost 4000 seeds) to the Encounter Bay seafloor.

“To ensure local provenance and genetic stability, fruit can be collected along beaches from the Bluff at Encounter Bay to the Murray Mouth at Goolwa. 

“Our holding tanks are at the Encounter Bay boat ramp and can be dropped off 24/7.

“We’re seeing the fruit wash up in WA and other parts of the SA coast which is a sign that we are not far away from seeing them on our beaches. 

“Anyone interested in receiving alerts and being part of the action is encouraged to sign up via the Seeds for Snapper page on the Landscapes Hills and Fleurieu website or at ozfish.org.au,” she says.

An extra benefit of seagrass restoration this year will be preservation of a famous local shipwreck.

“It’s early days, but we are also very excited to be working with the Department for Environment and Water and Flinders University this summer to deploy some of the seagrass sandbags around the well-known South Australia shipwreck at Yilki.

“Shipwreck preservation is obviously a very sensitive and scientific task, but establishing seagrass communities around the wreck will certainly help contribute to its preservation and protection from storm surges and exposure to destructive marine organisms,” Caroline says.

The Seeds for Snapper project is part of OzFish Unlimited’s national seagrass restoration program, funded on the Fleurieu Peninsula by Landscapes Hills and Fleurieu and BCF with support from Department for Environment and Water, Flinders University, SARDI Aquatic Sciences, local councils and community volunteers.

Find out more at the Landscape SA website.

Seagrass fruit containing seed. Image by Sarah Beara.