A big Cochlodinium bloom happened in the Pearl River Estuary in China in 2009. Scientists studied how this bloom affected the growth of other harmful algae in the area. They found that Cochlodinium was the main species in the bloom, and it inhibited the growth of Prorocentrum micans and Heterosigma akasiwo. However, it didn't stop the growth of Skeletonema costatum and even helped it grow a bit. The substances that caused the inhibition were mainly in the filtered bloom water and could withstand high temperatures.