Cockatoo Island / Wareamah Marine Restoration Pilot Project

The Cockatoo Island Marine Restoration Pilot Project, a collaborative initiative between the Sydney Institute of Marine Science (SIMS) and the Sydney Harbour Federation Trust (Harbour Trust), seeks to enhance marine biodiversity and expand our knowledge of the island’s marine environment.

Aligned with the Harbour Trust’s Cockatoo Island / Wareamah Master Plan, the project explores and trials ecological remediation methods, aiming for broader applications across the site.

Project Goals

Testing feasibility:

Assessing the potential for marine restoration in areas impacted by historical industrial activities.

Educational opportunities:

Creating interactive, interpretive spaces for visitors to learn about the vibrant marine life in Sydney Harbour.

Evaluating restoration techniques:

Developing methods that could be applied across Sydney Harbour to foster a healthier, more resilient marine ecosystem.

Key Milestones

A White’s seahorse captured on camera at Cockatoo Island via underwater drone.

Baseline Study (April 2024):

Using underwater drones, SIMS conducted a baseline study to map benthic and fish communities, water quality, and pollution levels around the island.

Results revealed a surprisingly healthy marine environment, including sightings of the endangered White’s seahorse, marking the farthest known extension of this species into the Port Jackson estuary!

Pregnant captive-bred White’s seahorses in Chowder Bay – Jayne Jenkins

Seahorse Hotels Installation (July 2024):

In collaboration with the Gamay Rangers, SIMS installed 20 seahorse hotels on the Eastern Apron of Cockatoo Island. These structures mimic natural habitats, providing a safe space for local seahorse populations and other marine life.

New Living Seawalls statue installation at Cockatoo Island – Aliah Banchik

Living Seawalls Installation (September 2024):

Living Seawalls were installed next to the public ferry wharf, featuring designs that mimic natural habitats and promote marine biodiversity. Over the next twelve months, SIMS will monitor these panels to track the marine life they attract, anticipating increased growth during warmer months.

Martina Doblin, Minister Plibersek, Janet Carding, Mariana Mayer Pinto – Aliah Banchik

Unveiling of Living Seawalls Installation by Minister of the Environment (October 2024):

The Minister for the Environment and Water, Tanya Plibersek, attended a private event to officially unveil the Living Seawalls installation adjacent to the public ferry wharf at Cockatoo Island.

White’s seahorse pre-release – Aliah Banchik

Seahorse Release at Cockatoo Island / Wareamah (February 2025):

200 captive-bred White’s seahorses into the Eastern Apron of Cockatoo Island, marking a significant step in ongoing efforts to support marine biodiversity in the Harbour. This release builds on the success of the seahorse hotels installed in July 2024, providing essential habitat for the endangered species.

This milestone is part of the broader Cockatoo Island/Wareamah Marine Restoration Pilot Project, supporting Sydney Harbour’s biodiversity recovery, a key action from the Cockatoo Island / Wareamah Master Plan is to support Sydney Harbour biodiversity and enhance rehabilitation of the waters around Cockatoo Island / Wareamah.

The History of Cockatoo Island / Wareamah

Cockatoo Island, February 1944. John Jeremy Collection

Cockatoo Island, traditionally known as Wareamah, is the largest island in Sydney Harbour, situated at the confluence of the Parramatta and Lane Cove rivers. It connects to the waterways and homelands of the Wallumedegal, Wangal, Cammeraygal, and Gadigal peoples.

Historically, the island underwent extensive transformation, evolving from a convict penal station in 1839 to a major shipbuilding yard in the mid-19th century. By the late 20th century, shipbuilding ceased, and the island transitioned into a cultural hub. In 2010, Cockatoo Island was inscribed on the UNESCO World Heritage List as part of the Australian Convict Sites World Heritage Property. Today, it serves as a vibrant destination managed by the Harbour Trust, known for its heritage, events, and harbourside camping.

Despite its bustling surface, the waters around Cockatoo Island have been largely overlooked. This project aims to shed light on the island’s underwater ecosystems and explore effective restoration methods that integrate its rich history with a renewed focus on marine conservation.

Future Plans

SIMS will now monitor these interventions (Living Seawalls and Seahorse Hotels) to ensure their success and hope to expand its remediation work across the island to other highly degraded areas to enhance the underwater environment at Cockatoo Island.

Follow SIMS and the Harbour Trust on social media for updates on these and future developments, as we strive to foster a healthier, more resilient marine ecosystem.