The Department of Fisheries commissioned the installation of a Nearshore Artificial Reef within the Port of Esperance, on the southern coast of Western Australia.
The seabed within the port has very little natural complex habitat and is characterised by low relief granite and seagrasses and sand seabeds. Fish assemblages are being observed to change with time as climate change promotes the migration of tropical herbivores further south (Kendrick, 2001).
In addition, anthropogenic impacts from fishing and the port have modified the habitats in Esperance Bay.
The fisheries department reinvest recreation fishing license funds into habitat projects annually. Subcon was engaged in the project to create purpose-built habitats which are an important fisheries management tool alongside catch limits and seasonal closures. Purpose-built habitats have been known to support schooling for planktivorous fish species that are typically being replaced by herbivores.
MMA performed the design, construction and installation of the reef which included 128 reef modules arranged in a bow tie layout.
A Community Effort
MMA fabricated the reef modules in Esperance, with the collaboration engaging local supporters in the stewardship of the reef. Learn more via our video here.
MMA also supported Recfishwest to establish ReefVision, a community program where local anglers are trained as citizen scientists to conduct the data collection.
The engineered reef included:
- 96 Apollo modules
- 16 Abitat modules
- 16 Bombora modules
Key Equipment / Installation Method
MMA employed the Dynamically Positioned (DP) Offshore Construction Vessel Guardian Supporter, an autopilot for ships, to install the modules. The use of this system makes installation fast and accurate in higher sea states - in this instance, the entire reef was installed in under 3 days.
MMA Innovation / Value Added
MMA has pioneered hands-free lifting and diver-less installation. The use of remote-operated tools resulted in a safer and faster operation, reducing our exposure to weather standby. Removing the divers means MMA can also install in deeper water.
This has in turn enabled one of our key innovations - the use of dynamically positioned vessels which again makes our operations much faster and more accurate.
What this means for our clients is bigger reefs. Because our installation is so efficient, we can increase the size of our reefs by 50% compared with what our clients were building 10 years ago.
We can exceed our clients’ expectations in terms of safety and install reefs in much more challenging conditions than was historically possible. A great outcome for the environment as well as fisheries managers, operators and recreational users of the reefs.