Climate change poses threat to nutritional benefits of oysters, scientists warn
A study found increased temperatures and carbon dioxide levels could reduce the levels of proteins, lipids and carbohydrates in oysters.
The nutritional qualities of shellfish could be significantly reduced by future ocean warming, a study suggests.
Research by the University of Plymouth found increased temperatures and carbon dioxide levels could lower the levels of proteins, lipids and carbohydrates in Pacific oysters.
During the study, oysters were subjected to six sets of ocean conditions over a 12-week period, from current temperatures and carbon dioxide levels to those predicted for the middle and end of the century.
The work, published in the journal Marine Environmental Research, also found changes in the composition of essential minerals in the oysters.
Dr Anaelle Lemasson, a former PhD student at the University of Plymouth, said: “Identifying changes in nutritional quality, as well as species most at risk, is crucial if societies are to secure food production.
“Our previous research had suggested there could be negative effects in the conditions predicted to occur in 2050 and 2100.
“However the fact that Pacific oysters, which currently accounts for around 90% of UK oyster production, can be affected could be a cause for concern.”
More than 15% of animal protein consumed around the world comes from seafood.
Scientists say those in the aquaculture industry may wish to consider a shift in focus towards species that are more robust to climate change and less prone to deterioration in quality.
Their research focused on the Pacific oyster, Magallana gigas, and the native flat oyster Ostrea edulis.
Results showed increased temperatures and carbon dioxide levels significantly reduced the Pacific oyster’s nutritional qualities.
Dr Antony Knights, associate professor in Marine Ecology, said: “Climate change and the growing global population are placing arguably unsustainable demands on sources of animal protein.
“This comes at a time when increased obesity in several regions of the world is leading to greater public awareness of the need for healthy and balanced diets.
“Oysters have the potential to be a sustainable, low-cost alternative source of protein for humans.
“Our native flat oyster, in particular, appears to be more resilient to future climate change scenarios than introduced Pacific oysters, making them a great aquaculture choice, and supports the growing investment in this product in the UK.”