Ocean acidification mitigation strategies for the mussel industry
We are testing techniques to raise the pH of coastal waters around mussel farms to improve shellfish growth.
Project leader: Cliff Law, NIWA/University of Otago
Duration: February 2017 – January 2019
Coastal waters are becoming more acidic due to increasing atmospheric carbon dioxide and local processes such as microbial respiration. This is a threat to Aotearoa New Zealand’s shellfish aquaculture industry, because mussels are less healthy and don’t grow as well at lower pH.
We are testing two techniques to see how effective they are at alleviating acidification around mussel farms. The first involves using waste mussel shells, which could raise pH and dissolved carbonate as they break down. The second is strategic aeration of farm waters at night, when oxygen and pH are naturally lower.
In May 2018, in collaboration with the New Zealand seafood company Sanford, we measured the impact of these techniques at one of their mussel farms. The results are being used in hydrodynamic models, to estimate the benefits for mussel farms at the top of the South Island. We will also test the impact of these techniques on the survival and condition of mussel spat and juveniles.
In addition to assisting the shellfish aquaculture industry, this research may contribute to mitigation of acidification in natural coastal ecosystems.
Latest news and updates
Kaikōura community members gathered on 10 April to hear from National Science Challenge researchers who have been working in the area since the 2016 quake.
Last week (4-8 March) the Sustainable Seas team were in Nelson on a LEARNZ virtual field trip. Sustainable Seas researchers talked to students from over 100 schools around New Zealand about ecosystem-based management, kaitiakitanga of the marine environment, ecosystem services and tracking plastics in our oceans.
We are pleased to welcome Joe Harawira and Ian Ruru to the Sustainable Seas National Science Challenge Kāhui Māori.