Our 5-year partnership with the Sydney Institute of Marine Science

Sydney Airport has launched a new five-year partnership with the Sydney Institute of Marine Science (SIMS) to help restore seagrass meadows in Botany Bay (Gamay).

The project will support hands-on restoration, scientific research and community and school education sessions.

With a $576,000 investment from Sydney Airport, the team from SIMS will be working with experts from the University of New South Wales (UNSW) and the Gamay Rangers to help bring seagrass back to areas where it has declined over time.

Why Sydney Airport is investing in this project

Sydney Airport has been part of Botany Bay (Gamay) since 1919 and recognises its role in helping care for the area.

As Sydney Airport General Manager, Environment and Sustainability Jake Atkins explains:

"Sydney Airport has been part of this bay for over 100 years and we want to support efforts to look after it for the future.”

The project brings together expertise from the Sydney Institute of Marine Science (SIMS), the University of New South Wales (UNSW) and the Gamay Rangers, combining science, culture and community involvement.

"By combining SIMS research expertise, Traditional Custodian knowledge and community involvement, this program is intended to support healthier marine environments and build knowledge that can inform future restoration efforts across the region,” said Jake Atkins.

SIMS Director and CEO Professor Martina Doblin said:

"By restoring seagrass, we're giving new life to the bay, and in doing so, we hope to inspire the people who love this place to help care for our coasts now and into the future."

Why seagrass matters

Seagrass might look simple, but it plays a vital role in keeping our oceans healthy.

Seagrass meadows:

• Can Provide habitat for hundreds of marine species

• Can Help keep water clean

• Can help Stabilise the seabed and protect coastlines

They can also play an important role in tackling climate change. Seagrass absorbs carbon dioxide from the water and can store four times more carbon than terrestrial rainforests.

Bringing in the experts

SIMS is working with scientists and researchers from the University of New South Wales (UNSW), who bring expertise in marine ecosystems and conservation.

UNSW Professor Adriana Vergés, who leads the project, highlighted both the challenge and the opportunity:

"In Gamay, nearly half of these seagrass habitats have been lost over time due to pollution and coastal development. Encouragingly, several areas of the bay are now stable and well suited to restoration."

"Partnerships like this are essential for scaling up our research and restoration efforts, helping us towards the goal of returning this vital ecosystem to parts of Gamay where it once thrived."

Caring for Sea Country

This teams from SIMS and UNSW are also working with Traditional Owners to care for Sea Country.

The Gamay Rangers will play a central role in replanting seagrass, drawing on cultural knowledge and local experience.

Established in 2019, the Gamay Rangers are an Indigenous Ranger team from the La Perouse Aboriginal community, working to care and protect the land and waters of their cultural area in Coastal Sydney. 

Gamay Rangers Manager Bryce Liddell said:

“It’s really valuable that Sydney Airport is contributing to replanting more seagrass meadows in the bay.”

“As saltwater people, we’ve grown up with a deep understanding of how this waterway behaves - how species move through it, when to harvest, and how to care for Sea Country the right way,” he said.

How the restoration project works

The project focuses on practical, science-led restoration.

It involves:

• Collecting naturally detached seagrass fragments washed up on local beaches

• Keeping them healthy in holding tanks

• Replanting them in suitable areas across the bay

Divers carefully plant the seagrass, with monitoring at three, six and twelve months to track survival and recovery.

Early work also focuses on identifying the best locations for long-term restoration and understanding how much carbon the seagrass stores.

Getting the community involved

Community involvement is a key part of the project.

Students from Kurnell Public School were the first to get a hands-on learning day at Silver Beach, helping them connect with the marine environment in their own backyard.

The year 5 and 6 students did a walk along the shoreline with the team from UNSW and the Gamay Rangers to learn about why seagrass is important and how to collect it for replanting.

Here’s what some of the students told us:

Will said:

“I got to learn all about seagrass and why it’s important, because it holds a lot of habitat for animals and if we lose it put the animals at risk. If you see seagrass on the beach and it still has the stem and is green, it can be replanted.

Maggie:

“I learnt that seagrass helps shelter little fish and seahorse. I’m now going to come to this beach and look for seagrass that can be replanted.”

Year 5 student, Knox said:

“I learnt that seagrass is a haven for many specifies like fish and crabs.”

Connor said:

“I think this program is great because we want to save seagrass from extinction.”

There will also be opportunities for community members to contribute directly—such as collecting seagrass fragments that wash up on local beaches.

Helping seahorses and marine life

Healthy seagrass meadows are home to many marine animals—including the endangered White’s Seahorse.

These seahorses rely on seagrass for survival, often wrapping their tails around seagrass leaves to stay anchored in the water.

When seagrass declines, these animals lose their homes. Habitat loss is one of the main reasons populations of seahorses and other species are under threat.

Restoring seagrass can helps rebuild these habitats—providing shelter, feeding grounds and safe places for young marine animals to grow.

Why seagrass has declined

Research shows seagrass meadows in Botany Bay have declined significantly over recent decades.

This decline may be linked to factors such as:

• Coastal development

• Changes in water quality

• Physical damage from boats, anchors and moorings

Seagrass is slow-growing and fragile. Once damaged, it can take decades to recover.

Meet Posidonia australis

The focus of this project is Posidonia australis — an species of seagrass found in southern Australia, including Botany Bay.

It has long, bright green leaves that can grow over 80cm and grows in sandy seabeds in shallow coastal waters.

In New South Wales, this species is classified as endangered.

Seagrass meadows formed by Posidonia australis are critical habitats, supporting a wide range of marine life and helping ecosystems thrive.

Caring for the bay together

Restoring seagrass is a long-term effort—but one that can bring lasting benefits for the environment, wildlife and community.

By combining science, cultural knowledge and local participation, this partnership aims to help rebuild the ecosystem that supports marine life and protects the coastline.