Collecting the book of life for coral reefs

Dr. Mary Hagedorn – Senior Research Scientist, Smithsonian Conservation Biology Institute/ Hawaii Institute of Marine Biology, Coconut Island, Hawaii

Article | 22 September 2021
For 17 years, Dr. Mary Hagedorn has been working in using human fertility techniques to save coral. Using cryopreservation, Mary and her team have been able to collect coral sperm and freeze them successfully. ILO Photos/ John Isaac
Surrounded by the brilliantly blue waters of Kāne‘ohe Bay, just off the coast of Hawaii’s Oahu island is Coconut Island. The 28-acre island is the only laboratory in the US built on a coral reef and serves as a research facility for the Hawaii Institute of Marine Biology (HIMB) and the University of Hawaii Manoa.

Dr. Mary Hagedorn, a senior research scientist at the Smithsonian Conservation Biology Institute, and her team of five are hard at work in their island lab on a mission to save coral reefs.

“It’s a really unique area in the US in that we have this coral bay that has all sort of patch reefs, barrier reefs and fringing reefs. We have all three kinds of reefs here and we have a small variety of maybe 15 species, and while that’s not much diversity, the coral are healthy and spawn regularly and that makes it very attractive for the reproductive work that we do,” Mary says. “Hawaii Institute of Marine Biology is a very sophisticated laboratory sitting on a coral reef basically.”

Although they look like rocks or plants, corals are animals. “It is a sessile animal, in that it glues itself down like a tree and it can’t move,” Mary explains. Using her hand to demonstrate she says, “coral creates its skeleton, like we create our skeleton, and it has a very thin veneer of skin on it, which is the coral animal, and can be easily destroyed. Therefore, we don’t want people walking on reefs and destroying all of the tissue that is the coral.”

For 17 years, Hagedorn has been working on “using human fertility techniques to save coral reefs,” of which more than 75% are under threat due to factors such as climate change, pollution, coastal development and both overfishing and destructive fishing.

While climate change in particular is the leading cause of coral bleaching, Mary says that we and “our overuse of fossil fuels,” are in fact the biggest threat to coral reefs.

Although they often look like plants or rocks, coral are animals, and can easily be destroyed. They are of great importance as they support roughly 25% of marine life, they help produce oxygen, protect our homes and cities, and are also important to tourism. ILO Photos/ John Isaac
Using “cryopreservation a relatively new field of science,” the process of preserving living cells and tissues at very low temperatures, Mary and her team have figured out how to collect sperm from corals during their spawning period and successfully freeze them. “Not only have we worked out those techniques for coral, but we’ve built the equipment to freeze them in too, and we actually apply it in the field,” she shares with much excitement about her pioneering work.

In addition to “sperm freezing,” which Hagedorn says is relatively easy, she and her colleague, fellow marine biologist John Daly, have used cryopreservation to make new coral and “have done a thing called assisted gene flow.” “What that means is we've taken sperm from one area, and crossed it with eggs from another area, that wouldn't ordinarily, meet geographically,” she explains.

“John did this at the Northern Great Barrier Reef with the Central Great Barrier Reef, the same species he crossed them. They are hundreds of kilometres apart and wouldn’t meet each other. We also did the same thing in the Caribbean and the reason we did this was proof of concept to show that we could use these frozen sperm in geographically distant places,” Mary highlights.

In speaking about saving coral, Hagedorn emphasizes why coral reefs are important. “They are important for life on Earth, and they support marine life. 25% of almost everything that lives in an ocean, lived on a coral reef at some point,” reveals Mary. “They are intimately involved in the production of oxygen on our planet, and they can protect our cities and homes from tsunamis and hurricanes, “she says, explaining that they offer “natural protections,” from “storm surges.” She adds that coral are also important to tourism, and “almost half a billion people rely directly on reefs for food and livelihood.”

“They are really important in our lives, even though they only take up a really small amount of real estate on the planet” she stresses further.

Working in their lab on Coconut Island, Mary and her team are constantly developing their research on coral preservation as well as training other researchers. ILO Photos/ John Isaac
Prior to her work with coral, on Coconut Island, Mary worked around the world including Africa and the Amazon. Growing up she actually wanted to be an astronaut. “I actually applied but my eyes weren’t sufficient to make the space program,” she says chuckling. “But I have always been interested in doing something different, and I like creating my own ideas and having my own way of doing things.”

A passionate marine biologist and cryobiologist, as a woman Hagedorn says that “there still is very much of a glass ceiling,” for women in the sciences. While she does her best to mentor other women and teaches university students, Mary believes more action needs to be taken to get more women involved in the sciences.

“I love to work! I really like to work!” Mary exclaims in talking about what work means to her. “My husband wants me to retire, but I love working and being busy,” she says with palpable enthusiasm. You get to interact socially with people in a way that you wouldn't necessarily if you were just working at home.”

“Our job is really not about today. It’s about 500 years from now when, hopefully, our oceans have come back to pre-industrial or near pre-industrial conditions,” Hagedorn says about the trajectory of her work.

“Honestly we're collecting the Book of Life for coral reefs and that's a significant thing,” Dr. Hagedorn says with a serene smile as the sound of the Kāne'ohe Bay waters lapping gently against the shore of Coconut Island can be heard in the background.