In a Cornell-led study, published Oct. 19 in the journal Ecological Applications, scientists report evidence of metal pollution creating danger for the soft coral sea fans.
“We know warming oceans pose an existential threat to coral reefs around the world,” said Allison Tracy, Ph.D. ’19, who conducted this work with Drew Harvell, professor of marine biology. “Action to alleviate the impact of warming oceans is a priority, but understanding the role of pollutants in coral disease and mortality gives us more options for solutions.”
While plastics and microplastics are a well-known threat to the world’s oceans, the effect of metal contamination is poorly understood, according to the researchers. Increased copper pollution can be a result of agricultural runoff and marine paint leaching from boat hulls.
Over a one-year period, the researchers tracked 175 individual sea fan colonies with varying levels of copper concentrations found in the sediment at 15 coral reef sites around Puerto Rico. They found that reefs with higher copper concentrations in the sediment suffered a reduction in recovery from multifocal purple spots disease – a disease that can plague the sea fans.