These two photos show the same prachtanemone in the Red Sea – on the left in 2022, on the right one year later. It can be clearly seen that the tentacles of the Anemone have shrunk and faded. They are fitted with high water temperatures. Because in warm water, the anemones, just like corals, dismiss their coloring symbiotic algae. Clown fish that live in the tentacles of these flower animals also suffer.
Adjacent to countries such as Egypt or Saudi Arabia, the Red Sea is surrounded by desert landscapes. The water is about 29 to 32 degrees warm and houses sea creatures that are adapted to these temperatures. But in the past three years, climate -related heat waves and rising temperatures are increasingly increasing to the Red Sea. For many of his reef dwellers, this was devastating, including for a well -known duo: clownfish and anemones.
“We always hope that anemones and clownfish groups will survive, as they have done again and again in the past ten years. But it was recently a point that was too extreme,” explains Morgan Bennet-Smith from Boston University. So far, coral reefs in the Red Sea have been considered particularly heat -resistant. “The fact that even this thermal refuge collapses in different ways is particularly frightening. It does not turn out to be the safe port for which we held it.” The anemons monitored by the research team around Bennet-Smith in the coral reefs of the Red Sea were fitted for about six months. As a result, 94 to 100 percent of the clown fish died and 66 to 94 percent of the anemons.
The anemones perish because they lack the nutrients of their symbiotic algae. But why do the fish die? A hypothesis for this can be seen in the photos: the clown fish are much better visible in front of the faded anemones. “The fish are more noticeable, spend more time outside the anemones, and are worse protected by the anemones,” explains co -author Peter Buston from Boston University. “The anemone fish are becoming easier to prey. They are not good swimmers and do not move away from their anemones, so that they are probably captured by predators.”
At the same time, the nettles of the faded anemones work worse and fire less poison ttsachel – they can therefore ward off the enemies of their fishing roommates worse. But even if they recover from the bleach, the danger is not over: as soon as the clown fish have disappeared, the flower animals are much more susceptible to their own predators, such as butterfly fish that feed on anemones. The research on the reef has the loss of these two important species, the researchers report.