Shuck Don't Chuck: shell recycling project

Growing native oysters for our reef restoration work can be a tricky business. In order to grow, juvenile oysters require a hard surface to settle on, preferably another oyster shell or something similar like a mussel or scallop shell. Historic dredge fishing removed much of the existing oyster shell from places like Port Phillip Bay in Victoria and Gulf St Vincent in South Australia. The resulting lack of hard shell substrate is one of the key factors preventing oyster reefs from re-establishing naturally in these areas.

Reinstating a natural cycle

To help reinvigorate this natural cycle, we set up a shell recycling project we call Shuck Don’t Chuck. Here’s how it works:

• Firstly we collect used oyster, mussel and scallop shells from restaurants, venues and seafood wholesalers in areas alongside some of our reef restoration projects. 
• Secondly, the shells are cured to kill off any diseases by laying them out in the sun for a few months. 
• When they’re ready they are bagged up and taken to our reef restoration sites. 
• Finally as part of the reef construction process, the tonnes of recycled shells are spread over limestone rubble we’ve already placed on the seafloor as a ‘settlement substrate’ for juvenile oysters to cement onto.

This technique has been used successfully by The Nature Conservancy in the United States and around the world for more than 15 years.