COCONUT ISLAND, Hawaii — Just before sunset, on the campus of the Hawaii Institute of Marine Biology, Mary Hagedorn waited for her mushroom corals to spawn.
As corals go, Fungia is fairly reliable, usually releasing its sperm and eggs two days after the full moon. Today was Day 3. “Sometimes we get skunked,” she fretted.
The recalcitrant corals sat outdoors in water-filled glass dishes, arranged in rows on a steel lab table. Each was about the size and shape of a portobello mushroom cap, with a sunburst of brown ribs radiating from a pink, tightly sealed mouth.
As Dr. Hagedorn and her assistant watched, one coral tightened its mouth and seemed to exhale, propelling a cloud of sperm into its bath with surprising vigor. The water bubbled like hot oatmeal.
A reproductive physiologist with the Smithsonian Institution, Dr. Hagedorn, 57, is building what is essentially a sperm bank for the world’s corals. She hopes her collection — gathered in recent years from corals in Hawaii, the Caribbean and Australia — will someday be used to restore and even rebuild damaged reefs.
She estimates that she has frozen one trillion coral sperm, enough to fertilize 500 million to one billion eggs. In addition, there are three billion frozen embryonic cells; some have characteristics of stem cells, meaning they may have the potential to grow into adult corals.
