BAYAHIBE, Dominican Republic — With an oxygen tank strapped to his back, Michael del Rosario moves his fins delicately as he glides through an underwater nursery off the coast of the Dominican Republic, proudly displaying “coral babies” growing on metal structures that look like large spiders. The conservationist enthusiastically points his finger at the largest corals, which are just beginning to show their vibrant colors.
Del Rosario helped plant these tiny animals in the nursery after they were conceived in an assisted reproduction laboratory run by the marine conservation organization Fundemar. In a process reminiscent of in vitro fertilization, the coral's egg and sperm combine to form a new individual.
This technique is gaining momentum in the Caribbean to counter sudden loss of corals because of climate changewho kills them warming oceans and makes it difficult for those who survive to reproduce naturally.
“We live on an island. We are completely dependent on the coral reefs and to see them all disappear is really depressing,” del Rosario said as he returned to the surface, his words flowing like bubbles underwater. “But seeing our coral babies growing alive in the sea gives us the hope we've been losing.”
Condition of corals around the Dominican Republic, just like in the rest of the worldnot encouraging. Fundemar's latest monitoring last year showed that 70% of the Dominican Republic's reefs have less than 5% coral cover. Healthy colonies are spaced so far apart that the likelihood of one coral's eggs meeting the sperm of another during the spawning season is reduced.
“This is why assisted reproduction programs are so important now: what was once the norm for coral reefs is probably no longer possible for many species,” said biologist Andreina Valdez, Fundemar's operations manager, at the organization's new marine research center. “And that’s where we come in to help a little.”
Although many people may think that corals are plants, they are actually animals. They spawn once a year, a few days after the full moon and at dusk, when they release millions of eggs and sperm, creating a spectacle that transforms the sea around them into something like the Milky Way. Fundemar monitors spawning periods, collects eggs and sperm, performs assisted fertilization in the laboratory, and cares for the larvae until they are strong enough to be transferred to the reef.
In the laboratory, Ariel Alvarez examines one of the star-shaped fragments on which corals grow under a microscope. They are so tiny that they are almost impossible to see with the naked eye. Alvarez turns off the lights, turns on the ultraviolet, and the coral's rounded, fractal shapes appear through a microscope camera projected onto a screen.
In one room of the research center there are dozens of aquariums, each containing hundreds of tiny corals waiting to be returned to the reef. Del Rosario said the lab produces more than 2.5 million coral embryos a year. Only 1% will survive in the ocean, but that figure is better than now with natural fertilization of these degraded reefs, he said.
In the past, Fundemar and other conservation organizations have pursued asexual reproduction. This meant cutting off a small piece of healthy coral and replanting it somewhere else so that a new one could grow. This method produces corals faster than assisted fertilization.
The problem, according to Andreina Valdez, is that he is cloning the same individual, meaning that all these corals have the same vulnerabilities to disease. In contrast, assisted sexual reproduction creates genetically different individuals, reducing the likelihood that one disease can affect them all.
Australia has become a pioneer in coral fertilization. It is expanding in the Caribbean, with flagship projects at the National Autonomous University of Mexico and the Carmabi Foundation in Curacao, as well as implementations in Puerto Rico, Cuba and Jamaica, Valdez said.
“You can't conserve something if you don't have it. So (these programs) help increase population numbers,” said Mark Eakin, corresponding secretary of the International Coral Reef Society and former director of the US National Oceanic and Atmospheric Administration's coral reef monitoring program.
But the world still needs to cope with the “800-pound gorilla of climate change,” Eakin said, or much of the recovery work “will simply be destroyed.”
The burning of fossil fuels such as oil, gas and coal produces greenhouse gases that trap heat in the atmosphere, raising temperatures both on the Earth's surface and in its seas. According to UNESCO's latest State of the Ocean report last year, oceans are warming twice as fast as they were 20 years ago.
And it's destructive to corals. The rising temperatures make them feel sick and expel the algae that live in their tissues and provide them with bright colors and food. This process is known as bleaching because it exposes the white skeleton of the coral. The corals may survive, but they will be weakened and vulnerable to disease and death if temperatures do not drop.
Half of the world's reefs have disappeared since 1950, according to a University of British Columbia study published in the journal One Earth.
For countries like the Dominican Republic, located in the so-called “hurricane corridor,” reef conservation is especially important. Coral skeletons help absorb wave energy, creating a natural barrier against stronger waves.
“What are we selling in the Dominican Republic? Beaches,” del Rosario said. “If we don't have coral, we'll lose coastal protection, we'll lose sand on our beaches and we'll lose tourism.”
Corals are also home to more than 25% of marine life, making them vital to the millions of people around the world who make their living from fishing.
Alido Luis Baez knows this well.
It's not yet dawn in Bayahibe when he boards a boat to go fishing with his father, who at 65 still goes to sea every week. The engine roars as they travel mile after mile until the coastline disappears into the horizon. To catch tuna, dorado or marlin, Luis Baez swims up to 50 miles from shore.
“We haven’t had to go this far before,” he said. “But due to overfishing, habitat loss and climate change, you now have to go a little further every day.”
That changed when his father, also named Alido Luis, started fishing in the 1970s. Then they went on a sailboat, and the coral reefs were so healthy that a lot of fish could be found close to the shore.
“I used to be a diver and caught a lot of lobsters and king shells,” he said, his voice weakened by time. “In a short time, I'd catch 50 or 60 pounds of fish. But now, to catch two or three fish, they spend all day there.”
Del Rosario said there is still time to stop reef destruction.
“Of course, more needs to be done… but we put a lot of effort and time into preserving what we love so much,” he said. “And we believe and trust that many people around the world are doing the same.”
___
Follow Teresa de Miguel on X on @tdemigueles
___
For more climate coverage, visit the AP website. http://www.apnews.com/climate-and-environment
___
The Associated Press' climate and environment coverage receives financial support from several private foundations. AP is solely responsible for all content. Find hotspots standards for working with charities, list of supporters and funded coverage areas on the website AP.org.
