Mote Marine Laboratory

Looking Beyond the Pretty Picture

By: Rebecca Evanhoe

Underwater, Carmen Powers watches as spike-backed, mottled hogfish wait patiently to be picked clean by tiny neon gobies. Pastel, bristle-topped Christmas tree worms spend time on their favorite coral tops, and fish dart in and out of coral nooks, their colors layered together like a waving patchwork quilt.

Visual bliss is what Powers sees when she dives the Florida Keys. “Schools of fish and vibrant colors. It’s life. You can see it all around when you dive. It’s like people walking the streets of New York.” But it’s not all hustle and bustle in Powers’ pulsing, moving world. She often finds spots where the corals have turned a cadaverous-looking white through coral bleaching.

The contrast between the busy  healthy reef and the skeletons left behind when corals bleach, and sometimes die, is stark. “Bleached corals are like a skeleton, white and bony — like a chicken bone, dead and dried out,” Powers says. Corals can recover from bleaching but if they don’t, such places are eventually deserted by fish as well, leaving a ghost town instead of a vibrant city.

Powers is one of more than 100 dedicated volunteers who watch these living coral ecosystems for signs of trouble. They alert scientists with Mote Marine Laboratory and the Florida Keys National Marine Sanctuary to signs of coral distress and bleaching.

The volunteer program called BleachWatch is modeled after a program on the Great Barrier Reef outside of Australia. Mote staff biologist Cory Walter has trained the volunteers to report coral bleaching events so managers with the Keys marine sanctuary can react to protect the reefs from further stress.

Signals of change

The National Oceanic and Atmospheric Administration, NOAA, has in-situ monitoring systems — buoys anchored in the ocean — that measure environmental conditions such as salinity. The agency also has satellites that monitor sea surface temperatures. Combined, these tools offer a best guess as to when corals will bleach, says Erich Bartels, manager for Mote’s Coral Reef Science and Monitoring Program. “NOAA has a fantastic monitoring system in place,” he says. “But it’s pretty hard to confirm when corals are actually responding when the models show they should be bleaching.”

These NOAA models only tell part of the story. The volunteers provide  a close-up look at the corals themselves to round out the picture. “Our data supplements what NOAA already has,” Bartels says. “Our observations will improve their forecasting abilities, so that eventually their satellite imagery and their in-situ systems out there can provide a more accurate picture of what’s going on.”

Every two weeks during warmer months, Bartels combines NOAA data with volunteer reports and issues a Current Conditions Report (http://www.mote.org/coralreef). Brian Keller, science coordinator for the Keys marine sanctuary, says the reports have added useful pieces to the bleaching puzzle. We saw this past summer that it really worked.  It was very accurate. Mote stuck with getting the information out and collecting observations from volunteers and that played a key role in our bleaching response.

Powers, a diver since the late 1970s, works for Abyss Diving Center in Marathon, Fla. She picked up a brochure about the BleachWatch program and contacted Walter. Once she learned more about the problem and the importance of monitoring the reef, diving took on a whole new meaning. “Pleasure diving is fun, but now there are other things I can contribute to. That’s even more gratifying,” she says. “I still have a lot to learn about coral in general. And that was my goal. But it became more of a passion.”

Reading the signs

Powers now takes underwater photographs of corals for BleachWatch at sites that Walter and Bartels don’t often get to observe. “I can see a change in some of the corals, the obvious changes. But through my photography, Cory is able to pick up on more subtle changes that I’m not skilled in picking up. I may be able to photograph a brain coral and photograph it a month later, so she can see more of what changes are happening.”

Of those observations, “some corroborate the model NOAA has already generated, and others point out holes in the model,” Bartels says. The advantages of using volunteers are numerous. First, the volunteers spot-check more places — patch reefs or secret spots often missed by research teams.

“The volunteers give us crucial data that helps other agencies like NOAA with ongoing research and provides early alerts on which types of corals are bleaching first,” says Walter, who trains volunteers personally and equips them with data sheets and waterproof wrist bands to help with coral identification. Volunteers need to know the differences between coral diseases and coral bleaching, as well as basic categories of corals, such as flowering and cup corals, brain corals, branching, encrusting and boulder corals, which are the most common types. They also need to know branching, pillar, leaf and plate corals, which are less common.

“You have to remember that corals are living organisms, so there’s a lot of variability in how they get sick,” Bartels says.

Volunteers trigger early warning bells for bleaching by identifying which coral species are the first to bleach — a good indicator that more widespread bleaching could follow. For example, “the fire coral is a good indicator of bleaching because it’s the first type to start bleaching. When our volunteers come to us and say, ‘We’re seeing fire coral bleaching, but nothing else,’ we’ll say, ‘Keep your eye open. More corals will start to bleach next,’” Bartels says.

The Bleachwatch Program isn’t intended to stop bleaching, but rather, to help scientists understand patterns and causes. “The program is going to give us more and more information about bleaching,” says Bartels. “But you have to understand that bleaching is a natural event. The question is, are we making it worse? And that’s a very, very hard question to answer. The more we learn over the years, the better we’ll understand the factors — natural or otherwise — that are causing an increase in coral bleaching throughout the world.”

Coral Bleaching: A primer

The “coral organism” that we see is actually two different types of creatures living together; coral polyps and algae called zooxanthellae (zo-zan-THEL-ee). The zooxanthellae live among the coral polyps, providing an extra food source by turning sunlight into energy, as land plants do. The colorful zooxanthellae give the corals the bright colors that we see.

Coral bleaching is a natural phenomenon that happens when certain conditions — water temperature, the saltiness of the ocean or the amount of sunlight reaching the corals — vary too far from normal. If the coral gets too stressed from changing conditions, the zooxanthellae often move out of the coral, leaving the coral polyps like empty rooms of an apartment building. With the zooxanthellae gone, the color leaves too. What’s left is a white, hard polyp that might die unless the zooxanthellae move back in.

Rescuing Reefs

Florida drivers have generated new dollars for coral reef research, education and conservation programs by buying a “Protect Our Reefs” specialty license plate. Sales have generated about $1.3 million.

In January 2006, a 10 member committee awarded the first round of grants to be funded by plate sales. Sixteen grants worth $295,000 were awarded to help pay for new scientific studies and programs designed to help educate the public about coral reefs and their roles in ocean ecosystems.

Florida’s coral reef generates more than $1.2 billion annually for the state’s economy as a primary attraction for snorkelers, divers, anglers, boaters and other tourists, said Bruce Frerer, chairman of the Protect Our Reefs grant committee. “The reef plays an extremely vital role in Florida — not just for the economy but toward protecting our coastlines and keeping marine animal populations healthy,” he said.

Click here to proudly display your support by purchasing a Protect Our Reefs Florida lisence plate!

Learn more about: Protecting Florida's Reefs

Love thy anemones. The marine organisms you love. The ones you don't. Pretty ones. Ugly ones. Healthy ones. Threatened ones. They're all essential parts of our world's oceans and they all need our help.