Fouling by Cliona (boring sponge)

Boring sponges from the genus Cliona are among the most conspicuous and destructive bioeroders of calcium carbonate substrates. Although several species may make up the boring sponge complex commonly found along the US Atlantic coast, Cliona celata is the largest and most prevalent of the clionaids that infest calcium carbonate substrates. Although the study of clionaid sponges dates back to the late 1800s, it wasn’t until the 1930s when clionaid sponges were recognized as problematic for oyster fisherman, and more recently were demonstrated to be harmful to oyster aquaculture. Studies since have focused on how the sponges bore into the substrate, the drivers of boring sponge distribution, their impacts on oysters and other calcifying organisms, and mitigation strategies for aquaculture. Here, we provide a brief overview of the genus, particularly the members that affect shellfish along the US Atlantic coast, including the history of discovery and study, taxonomy, life history, ecology, and impacts on shellfish, particularly oysters.