In Vitro Corals

Scientists Help Repropagate Vanishing Reefs

Warming seawater and increasing ocean acidity are damaging reef ecosystems around the world, and some scientists and environmentalists fear a worldwide collapse by 2050. Coral reefs are colonies of millions of tiny animals. In a single night, the corals join in casting a fog of sperm and eggs into the water to either fertilize and make baby coral larvae or settle back onto the reef, fostering growth.

Dirk Petersen, Ph.D., founder and executive director of Sexual Coral Reproduction, in Hilliard, Ohio, gathers sperm and eggs from corals, fertilizes them in a lab and returns the baby corals to the wild. “A bunch of us coral reef managers were just so sick of just watching things die,” says Laurie Raymundo, a biologist at the University of Guam. This kind of in vitro fertilization provides at least a glimmer of hope for the future.