High Levels of Carbon Dioxide Threaten Oyster Survival

Based on information presented at the Global Change and Global Science: Comparative Physiology in a Changing World conference, August 4-7, 2010 in Westminster, Colorado.

Inna Sokolova, associate professor of biology at the University of North Carolina at Charlotte, studies the affect of high carbon dioxide on oyster survival, growth and shell hardness. The results of her research suggest that creatures once thought to be fairly adaptable to changes in the environment, may be in serious trouble.

Photo of oyster courtesy of Inna Sokolova.

Her research group monitored oysters that were kept in high CO2 conditions. Juvenile oysters were affected the most by high CO2 conditions. These young oysters grow at a faster rate than the adults and need to use more energy for survival. There was a higher chance that juvenile oysters would die if kept in high CO2. They also had reduced growth of their shells and their soft bodies. The young oysters' shells were also more fragile and prone to breaking, potentially making them more susceptible to predators.

"Living in the high CO2 world may increase the cost of living which cuts into other energy expending pathways," says Sokolova via a press release. "Everyday maintenance becomes harder making it harder to live."

The effects on growth were less pronounced in the adult oysters since they don't grow as fast and have slower metabolisms than the juveniles.

The fact that the early life stages are more affected by high CO2, suggests that this may serve as a bottleneck for oyster decline. Sokolova says, "Expect to see huge effects on populations in the future."

Me thinks my oyster-eating days are numbered.