LIHUE — Peter Swarzenski scanned the coral reef beneath him for signs of disease. It was March and the California-based U.S. Geological Survey oceanographer was underwater, surveying the health of the coral at Makua (Tunnels) and Anini beaches. Swarzenski, who
LIHUE — Peter Swarzenski scanned the coral reef beneath him for signs of disease.
It was March and the California-based U.S. Geological Survey oceanographer was underwater, surveying the health of the coral at Makua (Tunnels) and Anini beaches.
Swarzenski, who specializes in the study of how groundwater reaches the coast, saw a lot of coral coated in a veneer of sediment from river and stream runoff, which washes out to sea every time it rains.
He also saw black band disease.
“I wasn’t taken aback by how bad it was,” Swarzenski said. “A lot of the corals are really stressed on the North Shore and on the north shores of a lot of the Hawaiian Islands because it’s high energy and there’s lots of material coming into the coast, and because it’s tremendously rainy.”
In the weeks before environmental officials announced that half the coral reef sites surveyed by state scientists in nearshore Kauai waters are plagued by black band disease — an outbreak described in a recent USGS report as an “epidemic” — Swarzenski and other specialists convened on Kauai in hopes of finding out what makes it tick. Biologists, geologists, marine disease experts and managers came to see the disease and strategize about how environmental drivers like groundwater might be inflaming it.
Represented at the meeting were members of the Department of Land and Natural Resources, U.S. Geological Survey, University of Hawaii, National Oceanic and Atmospheric Administration and Environmental Protection Agency.
Born from the meeting is a new project led by Swarzenski aimed at investigating the relationship between black band disease and groundwater, as well as other environmental factors like ocean tides and water temperature changes.
“What I would like to do in this project is look at what triggers these coral disease events,” he said. “Is it a land-based event? Is it related to currents and waves? Is it a physical event like a drop in temperature? That’s what we’ll be looking at.”
These experiments will likely be launched on Kauai’s North Shore next summer, Swarzenski said. The project is expected to last two to three years.
“What’s unique about this project is that we have this really integrated team of people with different expertise,” Swarzenski said. “We’re developing a project with both a physical and biological component.”
The black band disease was first spotted at low levels on Kauai in 2004, then identified on the North Shore of Kauai in 2012 at 10 times background levels, according to the DLNR. It continues to plague the three Montipora (rice) corals found around the island.
All told, 23 of the 47 sites surveyed by state researchers are being killed by black band disease, which derives its name from the black band lesion it forms on the coral. This lesion starts small and quickly progresses until the coral colony is dead.
The places most affected by the disease are the reefs surrounding Makua (Tunnels), Anini and Anahola beaches as well as Ahukini Landing.
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Brittany Lyte, environmental reporter, can be reached at 245-0441 or blyte@thegardenisland.com.
