Piloting Reef Ball Enhancement at Portarlington
In 2009 and again in 2012, the Victorian Fisheries Authority established a number of artificial reef locations across Port Phillip Bay, both for boaters and locations with near-shore access.
Artificial reef balls are made of concrete and designed to mimic natural rock structures, which are important habitats for marine organisms, particularly fish. The reef balls provide a substrate for these organisms to attach and grow, and also offer protection from predators.
After over a decade in the water, growth on a number of these structures is substantial, with adult native oysters, sponges and other colonising species attached. However, due to the spacing between the reefs, they are not reaching their full potential as fishing reefs, nor providing the broader range of ecosystem services and benefits, they could potentially provide by simply increasing the complexity of the reef footprint through the use of recycled shell material.
A prime example is the site adjacent to the Portarlington Breakwater. Whilst species have colonised the reef ball units, within the reef ball unit clusters, the bottom consists of bare sediments and presents an exciting opportunity. The site has huge potential for a healthier, resilient reef structure that provides benefits for local seagrass and many of the species fishers love to catch.
A recent pilot trial undertaken by local anglers, including OzFish Geelong chapter members and the Leopold Aquatic and Angling Club, saw over 500kg of shell deployed to the Portarlington reef balls in a proof of concept that demonstrated a fantastic example of rec fishers undertaking environmental stewardship and the proof of concept for the approach.
OzFishers bagged recycled shells supplied thanks to the Nature Conservancy into manageable units, transporting them to site with the help of Bellarine Fishing Charters, where they were dropped on site to “fill the gaps” of the reef ball site.
With the approach developed, more activities to expand on the work and the reef footprint will be occurring over the coming months to transform the reef balls into a thriving complex reef area. To evaluate the benefits of the work, citizen/angler science monitoring will be undertaken to assess the benefit of the supplementation to local fish populations and habitat diversity, including Baited Remote Underwater Video monitoring of fish species, and community days on- water with the OzFish Underwater ROV to get a fish eye view with local anglers.
With the linkages of sustainability, fisheries enhancement and social equity, access, and stewardship, the project provides a wide range of positive outcomes to Victoria’s fishing community far beyond healthier fishing locations.