Like other species, Elkhorn coral are threatened by climate change. Climate change refers to the general warming of earth's average temperature caused by carbon emissions. Warmer atmospheric temperatures incidentally also increase water temperature. As mentioned, Elkhorn coral have special algae called zooxanthellae, living on their tissues, which provide many benefits. However, when water temperatures warm, Elkhorn coral expel their zooxanthellae. Without their zooxanthellae, Elkhorn coral first lose their prime oxygen source, then color, and then usually die. In addition, climate change increases the severity and prevalence of storms, which can decimate Elkhorn coral populations.