Rising sea temperatures put seafood at risk
CLIMATE change and ocean acidification has the potential to reduce the quality of seafood.
According to new Southern Cross University research, it could also have flow-on effects for future food security and ecosystem stability.
The research was led by Associate Professors Kirsten Benkendorff and Brendan Kelaher, with PhD candidates Rick Tate, Roslizawati Ab Lah and Roselyn Valles-Regino, and has been published in the Journal of Experimental Marine Biology and Ecology and Marine Drugs.
Assoc Prof Benkendorff and the team exposed marine snails (whelks) to future ocean climate change conditions for 35 days to evaluate the impact.
"We found a clear deterioration in nutritional quality, which may impact both the value and sustainability of whelk fisheries in the future,” she said.
"There were clear signs of physiological stress leading to reduced energy reserves for growth, survival and reproduction.
"The most significant finding was the massive drop in protein.
"The lipid content of the whelk flesh was reduced by half under elevated temperature and the proportion of healthy polyunsaturated fatty acids (omega 3 and omega 6) was reduced by elevated temperature but not acidification.”
Assoc Prof Benkendorff said whelks were predatory molluscs eaten around the world, with large markets in China, Korea, India and South America.
The experiment was conducted at the university's National Marine Science Centre in Coffs Harbour, which has facilities to simulate ocean warming.
Assoc Prof Kelaher said the seawater in the experiments was warmed and acidified to replicate ocean conditions predicted for the year 2100.
"These findings suggest a double whammy for sustainable fisheries,” he said.
"If the quality of seafood is less in the future, people will have to eat more fish from climate-impacted fish stocks to get the same nutritional benefits.”
Assoc Prof Benkendorff said few had investigated potential consequences of ocean change on the quality of seafood for human consumption. She said the study highlighted the need for further research into a range of species.