Anemones True Colors
The bleaching of these colorful cnidarians is due to the loss of symbiotic algae because of climate change.
Climate change is causing some tropical sea anemones to lose their color. This is the same bleaching that makes the news when warming ocean temperatures cause coral reefs to lose their color and turn white. The bleaching of these cnidarians is because they lose their symbiotic algae that give the anemones their color.
Bleaching also affects the clownfish, which rely on the anemones for shelter, breeding and nutrition. In one study on in the Gulf of Eilat (Aqaba) Red Sea, from 1997 to 2015 the number of the two different anemone species declined by 86% and their clownfish by 74%.
Resilient Venom
But, it’s not all doom and gloom for the anemones. Scientists found that even though anemones (Entacmaea quadricolor) living along the coast of Australia lost their symbiotic algae and bleached, their nematocyst venom was still effective and the anemones stayed alive by catching prey. This shows anemone resilience – good for the anemones and the clownfish that make these anemones their home.