Author: Sharon Hook, Principal Research Scientist, CSIRO

Sydney’s popular Coogee beach has been closed until further notice after hundreds of strange black balls washed up on the shoreline. The black balls were discovered on Tuesday afternoon. Randwick City Council The balls were discovered on Tuesday afternoon. The local authority, Randwick City Council, says samples have been collected for testing, and the incident has been reported to the Environment Protection Authority and Beachwatch NSW. A council spokesperson said the debris may be “tar balls” formed when oil comes into contact with debris and water – typically the result of oil spills or seepage. I am a senior research…