For the past seven months I've observed ghostly anemones in caves (no sunlight for the zooxanthellae to photosynthesize). I've also seen pallid anemones in tidepools with an influx of freshwater (an osmotic emergency for the anemones). But here's the weird thing: I’ve been seeing colorless giant green anemones in direct sunlight with no freshwater runoff.
Could the warm ocean temperatures the Pacific Northwest is experiencing be stressing anemones and causing them to expel their zooxanthellae, leaving them pallid ghosts of their formerly colorful selves?
I came across a study that makes me think my bleaching suspicions aren't completely crazy:
“Our study showed that at least seven of the ten anemone species suffer from bleaching when water temperatures get too high,” said study researcher Ashley Frisch of the ARC Centre of Excellence for Coral Reef Studies at James Cook University. “Importantly, we found bleaching of anemones occurring wherever we looked – from the Red Sea and Indian Ocean to the Indo-Australian region and the Pacific. Sometimes it was on a massive scale.”