Could Artificial Insemination Save Coral Reefs?

Marine biologists are borrowing from medical and
veterinary science in a bold experiment to create a sperm bank that could save
the world’s coral reefs.

Scientists led by Dr. Mary Hagedorn from the Smithsonian
Institution are harvesting coral eggs and sperm from sites in Hawaii, Australia
and the Caribbean with an eye toward restoring and rebuilding reefs damaged
reefs, reports The New York Times.

Coral reproduces asexually, meaning that clones can grow from
"parent" fragments, but genetic diversity depends on sexual
reproduction.

To date, the team has frozen one trillion coral sperm,
enough to fertilize 500 million to 1 billion eggs, along with 3 billion
embryonic cells, the Times reports. 

That bank could be the key to saving coral reefs around
the world that have been devastated by climate change: as the oceans warm, they
become more susceptible to disease and to "bleaching," which starves
reefs of the algae that is part of their food supply.

“Reefs at Risk Revisited,” released by the World
Resources Institute in February 2011, estimates at least 75% of the world’s
coral reefs are currently threatened by local and global pressures. Aside from
climate change and ocean acidification, factors such as overfishing, coastal
development and pollution pose the most immediate and direct risks,
threatening more than 60% of coral reefs today.

In some areas of the world, the prognosis is even more
grim. In the Caribbean, up to 80% of the region’s coral has been destroyed, reports the Times. Just
ask an avid scuba diver: the reefs look dramatically different than they did
just 10 years ago.

For now, team’s activities are limited to sperm and egg harvesting expeditions around the world, but their bank could be an insurance policy if reef conservation efforts fail.

If the current rate of decline continues, most
of the world’s reefs could be gone by 2050 — which would, in turn, threaten the
estimated one-quarter of all marine species that rely on its existence, reports the Times.

"Protecting fish communities, making sure water quality
is good, all of those efforts can buy decades of time," Nancy Knowlton, a
prominent coral-reef biologist at the Smithsonian, told the Times. "But if we
continue on this greenhouse-gas emissions trajectory, the only place we’re
going to be able to find many corals will be in Mary’s freezers."

[via The New York Times]

For more on the threat to coral reefs: