Community briefing provides details of coral disease along North Shore

HANALEI — Close to 100 people gathered in Hanalei Thursday to hear from University of Hawai‘i experts about the recent outbreak of a cyanobacterial coral disease along Kaua‘i’s North Shore.

Organized by Kaua‘i Mayor Bernard Carvalho Jr., the community briefing included presentations from Dr. Greta Aeby, assistant researcher for the Hawai‘i Institute of Marine Biology, and Sean Callahan, a professor in UH’s Department of Microbiology. Both are involved in the ongoing disease study.

“I was asked by the mayor to put together this briefing so that we could get some great information on an issue that we all need to be concerned about,” county spokeswoman Beth Tokioka said to kick off the meeting. “A few weeks ago the mayor and I were meeting with some folks from NOAA (National Oceanic and Atmospheric Administration), and just before that an article had come out in (The Garden Island) talking about the coral disease that we’re going to be hearing about today. Some words were used in that article like ‘epidemic’ and ‘disease’ … those kinds of words make people emotional and concerned.”

Tokioka took a moment to acknowledge and thank several people in the room, including William Aila, director of the Hawai‘i Department of Land and Natural Resources, Don Heacock, the Kaua‘i district aquatic biologist at the DLNR’s Division of Aquatic Resources, Mike Mitchell of the U.S. Fish and Wildlife and Mauna Kea Trask from the Kaua‘i County Attorney’s Office.

“I think you’re going to find this very interesting and enlightening,” Tokioka said. “We’re all here to listen, primarily, and learn. And think about what the next steps are.”

As Aeby began her presentation, cards were distributed around the crowded room so that those in attendance could have their questions answered.

“First off, I’d like to thank all of you for coming because that indicates an interest in our reefs here in Hawai‘i and that’s very important,” Aeby said.

Aeby began by giving the basic definition of “disease” and explaining that just because there is disease in an organism’s population, that doesn’t mean there is anything wrong with the organism or its ecosystem.

“We get sick, we get better,” she said. “Corals are animals. Corals get sick just like we do. But it’s the levels of disease that worries us.”

When corals get sick, Aeby said a few things happen — they will either lose tissue, become discolored or grow tumors.  

One question Aeby said people often ask her is “Why should we care about the coral reefs?”

“What we have to understand is that the coral reefs are the foundation species,” she said. “They build the homes for all the small, little critters, that then the bigger critters eat.”

If you have a collapse of the coral reef ecosystems you lose everything, she said.

In addition, coral reefs protect shorelines, produce beach sand and surf spots, build islands and fuel tourism.

Aeby then went into some background about how to keep corals healthy. She said humans like to live in coastal areas and that coastal development leads to problems — including nutrient runoff, sedimentation and pollution — which create conditions that are not conducive to the clean, clear, warm water corals need to survive.

“The other thing to understand about corals is that these animals grow very slowly,” Aeby said. “When you start losing these reefs, it takes a long time to heal.”

Aeby discussed the Florida Keys, where she said coral disease “has been rearing its ugly head” since the 1980s.

“What we’re seeing here in Hawai‘i is a pattern that has started to follow the same pattern that the Florida Keys saw back in the 80s,” she said.

The difference is that in the Florida Keys and the Caribbean scientists did not have hindsight, according to Aeby. Here in Hawai‘i, she said we do.

Like similar outbreaks in Kane‘ohe Bay and on Maui, Aeby said the level of disease on Kaua‘i’s North Shore are concerning and scientifically qualify as an epidemic.

“What we were finding was prevalence significantly higher than what the background levels should be,” she said. “This is a fairly virulent disease. This is killing off the coral.”

The good news, Aeby said, is that when she came back to Kaua‘i at the end of November, the disease had slowed down significantly at her test sites.

“Where it was 6 percent (prevalence) at ‘Anini Beach, it was down to 2 percent,” she said. “So that’s good. And that’s what happened in Kane‘ohe Bay too. There was an outbreak and then it slowed down.”

Before turning things over to Callahan, Aeby quickly discussed a treatment method, called lesion occlusion, which she and other scientists are using at ‘Anini. The method uses a marine epoxy to stop the disease from spreading — similar to a fire break approach during a forest fire.

Untreated coral colonies at ‘Anini had an average tissue loss of 18 centimeters in two months, Aeby said. But of the eight colonies that were treated, four stopped the disease altogether. The colonies where the disease did get past the epoxy had an average tissue loss of 6 centimeters.

“This was a very good first start in disease treatment,” Aeby said.

Callahan briefly discussed the work he is doing in his lab, which includes isolating and culturing the cyanobacteria found in the disease and trying to recreating the disease on healthy coral collected from Kane‘ohe Bay.

“If we can (recreate the disease), then clearly we’ve identified a pathogen,” he said. “We haven’t been able to completely recreate the disease at this point.”

In summary, Aeby said the disease on Kaua‘i is chronic, has reached outbreak levels at ‘Anini and Makua, kills corals, is probably caused by a cyanobacterial infection and that the method of disease treatment has helped slow or stop the disease.

“There’s clearly some sediment problems, at least at ‘Anini Beach,” she added. “Regardless of coral disease, poor water quality and sedimentation kills coral, especially if it’s a chronic issue.”

As far as solutions, Aeby says scientists need to do further research (distribution and prevalence, environmental drivers and disease ecology) and management (address underlying environmental stressors, rapid response team during outbreaks and treatment).

“We’ve got a window of opportunity here in Hawai‘i, but that window is starting to narrow,” she said.

Aeby discussed Hawai‘i’s underfunded Rapid Response Contingency Plan, a three-tiered program developed in 2008 with teams on O‘ahu, Big Island and Maui. The plan includes primary reporting from reef users, followed by confirmation by scientists and, finally, a rapid response team of trained experts.

“What we realized is this first tier is the most important,” she said. “One thing we know about Hawai‘i’s reefs is there’s bunches of them and there is very limited scientific and management oversight. They just don’t have the personnel.”

As for whether it is too late to save Kaua‘i’s reefs, Aeby said “not by any means.”

“We still have some good reef systems out here,” she said. “But … we’ve had four disease outbreaks in the last five years in the state of Hawai‘i, that’s what concerns me.”

Approximately 25 questions were fielded from the audience covering a wide range of topics. Many could not be answered because of a lack of research as the study is still in its early stages.

“We’re hoping to get more research out there so we can answer all these questions,” Aeby said at one point.

One big question was whether the bacteria could potentially be harmful to humans, which Aeby said is a question for the Department of Health, which did not send a representative to the meeting despite an invitation from the county.

• Chris D’Angelo, lifestyle writer, can be reached at 245-3681 (ext. 241) or lifestyle@thegardenisland.com.