UH Hilo MEGA Lab: Olympic tower construction could damage Tahiti reef ecosystem

Posted on by

A collaborative study, headed by UH Hilo’s MEGA Lab assessing the importance of protecting the valuable reef, is now published.

Surfer on a large wave.
Teahupoʻo, Tahiti, French Polynesia. (Photo: Wikimedia)
Beautiful green mountainous island with bay in foreground.
The Teahupoʻo community is concerned about impacts of tower construction. (Photo credit: Todd Glaser)

Pushing back against plans to build an aluminum judging tower for the Paris 2024 Olympic surfing competition in Teahupoʻo, Tahiti, marine scientist from the MEGA Lab at the University of Hawaiʻi at Hilo have headed a study conducted in collaboration with UH Mānoa, Arizona State University, and community partners in Tahiti.

The study, “Community-Based Monitoring for Rapid Assessment of Nearshore Coral Reefs Amid Disturbances in Teahupo’o, Tahiti,” is published in in Remote Sensing (Feb. 2024), assessing the importance of protecting the valuable reef, both as an integral part of the ecosystem and a resource for the local community.

Teahupoʻo, with an outer reef, is known for its surf break. The researchers used 3D photogrammetry techniques, the hallmark of UH Hilo’s MEGA Lab, and created high resolution maps of the reef and surrounding area. The team identified all coral colonies and living reef organisms. “In the 322 square meters (about the size of a tennis court) we identified the presence of 1,003 corals from 20 different species, indicating this site is a diverse and thriving coral habitat,” the researchers note.

Aerial view of reef with sections magnified to see details of the reef.
From the study: Imagery and orthophotos of the Teahupoʻo Lagoon and the three study site locations: Tower Footings Plot, Lagoon Plot 1, and Lagoon Plot 2. The inset orthophotos were generated by the community-based surveys and the larger lagoon orthophoto was rendered from UAV imagery. The proposed dredge area is a 6 m wide path from shore to the tower footings, highlighted by the grey rectangle. (Images: MEGA Lab/UH Hilo)

Although there is an existing judging tower used by the World Surf League, the Paris 2024 Olympic organizers intend to invest approximately $5 million USD to construct a substantially larger tower to provide amenities for judges including toilets, air conditioning, and capacity for 40 people.

John Burns casual portrait in black t-shirt, outdoor setting.
John Burns (Photo: Todd Glaser)

“We hope the International Olympic Committee, appropriate government officials and the greater international community can see how devastating this impact will be to not only the valuable coral reef habitat, but also the local community who depend on this reef for their livelihood and well-being,” says John Burns, a UH Hilo associate professor in marine science and data science and lead author of the study.

MEGA Lab

MEGA Lab is run by founder Burns, a research scientist primarily studying coral health and disease; specifically, he is investigating the physiological impacts of disease on affected corals and how coral mortality affects the ecology and biology of coral reef ecosystems.

Burns is an alumnus of UH Hilo and returned to his alma mater in 2018 as faculty where he quickly merged the disciplines of marine science and data science to develop the MEGA Lab, the base headquarters for his research and where he collaboratively works with scientists from around the world and trains students in advanced technologies such as data collection for 3D imaging of reefs. This remarkable 3D mapping of coral reefs is a hallmark of Burns’s work, and he is known for including his students in this research both in the open ocean and in the MEGA Lab.

The lab has conducted reef mapping at Oʻahu’s Banzai Pipeline and Fiji’s Cloudbreak, both with world famous surf breaks caused by reefs.

MEGA lab team poses in outdoor setting.
The MEGA Lab team, from left, Haunani Kane (UH Mānoa), Cliff Kapono (Arizona State University), John Burns (UH Hilo), Maluhia Kinimaka (UH Mānoa), and Kailey Pascoe (Arizona State University). (Courtesy photo)

Mapping the potential impact

In addition to an assessment of the reef in Tahiti where the Olympic structure will be built, the team mapped the lagoon area where the reef is being dredged to accommodate barge transport of tower materials. This dredging could directly impact 2,500-square meters of the reef (about half the size of a football field). If this were to occur, the authors report, it could cause a financial impact of at least $1.3 million by damaging the live reef habitat.

The team’s impact estimates are conservative — only accounting for direct impacts and not including the potential financial impacts for communities who depend on these resources or the impact on the much greater lagoon area if water quality is affected.

Several images of corals that make up the reef.
From the study of the reef at Teahupoʻo, Tahiti: Orthomosaic images of the study plots and individual coral colonies (inset images) at various spatial resolutions rendered from the 3D reconstructions at (a) the Tower Footings Plot, (b) Lagoon Plot 1, and (c) Lagoon Plot 2. (Images: MEGA Lab/UH Hilo)

The researchers teamed up with community members from Vai Ara O Teahupoʻo and used 3D photogrammetry techniques to create high-resolution habitat maps of three sites that will be impacted by dredging and tower construction. The resulting mosaics were analyzed to quantify species diversity, coral colony count, coral colony size, and percent of the ocean floor covered by live coral and other living organisms.

Read full story by Marcie Grabowski at UH System News.

Share this story