Exploring Causes of Coral Disease
The Hawaiian Islands’ beautiful ocean and beaches attract more than 8.5 million tourists each year. The USGS aims to help Hawaii preserve its underwater natural resources by tracing how oceanography may influence coral disease outbreaks. Looking into contaminants in the freshwater, or how quickly a bay may or may not flush, will help enrich future and past studies about the disease itself.
Location Taken: Kauai, HI, US
Video Credits: Division of Aquatic Resources University of Hilo ; National Oceanic and Atmospheric Administration ; USGS Coastal and Marine Geology Program ; Florida and Kauai Black Band photos by Christina Kellogg ; Princeville shot by Larry Loos, creative commons license 2.0 ; Music by Blue Dot Sessions "Union Hall" (License CC BY-NC 4.0) freemusicarchive.org/music/Blue_Dot_Sessions/Union_Hall/Union_Hall_Melody ; For more info visit: dlnr.hawaii.gov/reefresponse/kaua%CA%BBi-black-band-disease/
Opening scene shows water lapping at the camera and then following a USGS researcher underwater in Kauai during narration.
NARRATION: After reports surfaced of a coral disease along just one island in Hawaii, USGS scientists decided to dive in to Kauai’s waters during the spring of 2015 to investigate if such things as freshwater and nutrient input, may be the culprit.
Curt Storlazzi, USGS oceanographer: “We’ve been out here trying to understand potential environmental drivers of coral disease on the north shore of Kauai. We’ve seen that there’s a lot of stressors on the coral, so it’s not a simple, “Okay this is the driver that causes that.”
Background shows Curt pointing out and documenting some diseased-looking corals. Examples of environmental drivers listed are coastal pollution, sediment runoff, increasing ocean temperatures.
To complement the biological studies already done by their Hawaiian colleagues, USGS wanted to check water temperature, salinity, and whether water running off the land may be affecting coral health. They did some initial surveys above and below water, in an undeniably picturesque setting.
(Some shots of corals and above ground footage of running waterfalls and streams on the north shore of Kauai in addition to panoramas of Hanalei Bay and ocean view at Tunnels Beach.)
During music the video montage of fieldwork shows traveling with gear, getting into the car, driving and walking to Ke’e Beach, holding a salinity/temperature/pH probe and thermal infrared camera, getting ready to deploy small conductivity and temperature sensors, four researchers all separately walking into the ocean with snorkel gear, the center director retrieving gear, snorkeling and tying gear underwater.
Christina Kellogg, USGS microbiologist: “I am a microbiologist who mostly works on corals, both shallow water and deep-sea. Corals, like us, are an organism that has symbiotic microbes as a critical part of its biology. So disease is when that balance between the microbes and the host gets messed up by something.”
(Background shows Chris taking pictures of corals underwater and shots of a reef that is very sediment-laden)
Narration: Why corals become more vulnerable to microbes is the mystery. Is it favorable conditions that encourage overgrowth of the bacteria, OR unfavorable conditions that lower the coral’s immunity against disease?
Chris: “So we know black band is a polymicrobial disease, which means there’s more than one microbe involved in causing it. There’s almost always a cyanobacteria involved; in fact that’s what gives it its color. But there’s also a couple different bacteria involved in the sulfur cycle and it’s that combination that causes the tissue lysis that we see as disease.”
Still images of black band disease in Kauai and Florida are shown, both brain coral and mountainous star coral in 2010. Definitions pop up for cyanobacteria (blue-green bacteria that can photosynthesize) and for tissue lysis (cell destruction).
Narration: This black band clearly delineates live from dead tissues. When a disease forces coral to lose its colorful tissue, a white skeleton remains behind. This open real estate can be rapidly taken over by other algae.
Here a picture of black band disease is next to one that clearly shows a coral bleached white without its algae. This view pans to video of a shoreline with bright green algae along the rocks and Peter Swarzenski standing.
A bright green algae found along the shoreline can tell a different story—it’s usually a sign to Peter Swarzenski that cooler groundwater may be seeping into the ocean nearby, which can carry with it fertilizers and nutrients that upset the balance of a coastal ecosystem.
Shots of a nearby taro field and shots of the entire Hanalei Bay. This view pans to a shot of Chris, Curt, and Peter in flight suits for a helicopter ride and then to an example of the small instruments they will use instead.
Finding that cooler groundwater can be done by recording ocean temperatures using a thermal infrared camera. But the team’s plan to fly a helicopter along the north shore was thwarted by Kauai’s rainy weather. So they were able to collect some temperature data with these small instruments.
Peter Swarzenski, USGS oceanographer: “This measures conductivity and temperature. So the idea is that these float and we’re gonna get readings of just the surface of the ocean, the skin of the ocean.”
He’s holding an instrument with an orange float to point out the conductivity and temperature sensor. Then visuals go to an image of it floating on top of the water. The next shot is of tourists enjoying swimming in the water.
As USGS scientists investigate the causes of this disease over the next few years, tourists will continue to flock to Kauai’s oceanfront.
Chris: “…because what do people want to see? They want to see vibrant reefs with healthy corals and lots of fish. If you don’t have healthy corals then you are also not going to have the same fish species, and a lot of the fish species are things that are yummy to eat. If you don’t have reefs to protect the coastline you end up getting erosion so you might lose the beautiful beaches, which are also important for tourism, but also for protection for people who have built houses that close to the beach.”
Final moving imagery shows two snorkelers, a school of fish and diving turtle, a close up of a coral, then a panorama of Tunnel beach and two different areas of development near the water’s edge. Last image shows Curt snorkeling to the surface past the camera, with the words, “to be continued”
Final slide of credits:
Thanks to the
Division of Aquatic Resources
University of Hilo
National Oceanic and Atmospheric Administration
USGS Coastal and Marine Geology Program
Directed and produced by Amy West
Florida and Kauai Black Band photos by Christina Kellogg
For more info visit
Music by Blue Dot Sessions "Union Hall" (License CC BY-NC 4.0)