The New Zealand Greenshell Mussel is showing resilience in the face of future ocean acidification, the Cawthron Institute says.
Cawthron Institute research scientist Norman Ragg said early findings from its Greenshell Mussel ocean acidification breeding trials showed different mussel families had varying resilience to ocean acidification during the fragile early life stages.
“When we’re talking about a mussel family, it’s exactly that, a single mother and a single father in the traditional sense of the word,” Ragg said.
The research focuses on determining how the Greenshell Mussel species will respond to ocean acidification through breeding trials.
Ocean acidification is a worldwide climate change phenomenon. As the level of carbon dioxide in the atmosphere increases, the acidity of seawater around the world is slowly increasing, therefore the pH of the water changes as well.
Ragg said it had used Greenshell Mussels from all over New Zealand for this experiment.
“We can basically say that in this experiment we have a snapshot of most of the dynamics of the species.”
Ragg said over the course of two days, the team created 96 new mussel families for the experiment.
The adult mussels were kept in seawater of varying relative acidity.
After months in that environment, scientists induced spawning and monitored the offspring’s growth and survival.
Through their trials, Ragg and his team have discovered the pH change of the seawater makes it difficult for young mussels to grow their hard shells, meaning some babies will not survive the vulnerable first 48 hours of life.
Ragg said that the research team had also been studying whether the experiences of adult mussels, such as growing up in more acidic seawater, were reflected in the resilience of their babies and he said there appeared to be a correlation.
“They suggest adult mussels who experienced relatively acidic seawater have more tolerant offspring than adults without this exposure. This is a major discovery,” he said.
Ragg said Greenshell Mussels seemed to have a natural resilience, which was “fantastic news”.
“There’s a real diversity across the gene pool and there is a genetic capacity to change.
“If things got really bad really quickly you still have that genetic capacity to change.”
These trials are part of the wider coastal acidification rate, impacts and management project (CARIM), which aims to develop ocean acidification knowledge to enhance the protection and management of New Zealand coastal ecosystems.
CARIM is a four year NIWA-led collaboration, which includes partners Cawthron, University of Auckland, and University of Otago, and is funded by Ministry of Business, Innovation and Employment.
Sara Meij, Nelson Mail, 14 June 2014. Article.
