Release of symbiotic algae by tropical sea anemones and corals after cold shock

Abstract

When the tropical sea anemones Aiptasia pulchella and A. pallida are exposed briefly to subnormal temperatures then rewarmed to ambient temperatures, they release substantial numbers of zooxanthellae. Release consists of dissociation of zooxanthellae from the endoderm as a result of cold shock, and expulsion of zooxanthellae from the coelenteron after rewarming. Eleven species of scleractinian corals from the Seychelles Is., St. Croix, and Hawaii also released zooxanthellae after a 4 h cold shock between 12-18°C. Release at 12°C ranged from 20-75% after 12 h, depending on species, geographic location, and duration of cold shock. -from Authors