Picture credit: Peter Edmunds

In recent years, scientists have discovered a harmful algae called Peyssonnelid algal crusts (or PAC algae), which is an aggressive algae that is growing on Caribbean corals throughout the reefs and killing the baby coral. 

PAC algae is believed to be a result of global warming. Professor Peter Edmunds of California State University Northridge said, “People have been worried about hurricanes and their impact on the reefs. People have been worried about diseases, worried about bleaching, worried about pollution and worried about climate change. While people have been focused on those things, this alga has been creeping in and gobbling up space.”

To grow reefs, baby corals have to attach to a place near the ocean floor, and they prefer to settle on crusty surfaces. The crusty PAC algae is similar to the algae that creates nice, unharmful surfaces, tricking baby corals into thinking that this is the nice alga. However, PAC algae creates a microbial community that is fatal to the coral reefs and is threatening the natural coral habitat and Caribbean ecosystem. 

Although marine biologists have been studying PAC algae, they have not yet discovered an effective solution to the problem. Professor Peter Edmunds of California State University Northridge said: ‘What we do know is that this is an alarming trend, and one we need to know more about. The coral and their ecosystem are so fragile as it is. They are under assault by environmental pollution and global warming.” 

While this problem has so far been limited to the Caribbean coral reefs, it is just another reminder of the unprecedented consequences that will likely continue to emerge as a result of global warming and climate change.