Sur Ridge’s Living Laboratory:
Beauty, Mystery, and Conservation of Deep-Sea Corals
By Sadie Gardiner and Maya Bañuelos
August 25, 2026
NOAA’s Monterey Bay National Marine Sanctuary and the Monterey Bay Aquarium Research Institute (MBARI) have a long history of collaborating to understand deep-sea ecosystems. For 13 years, NOAA and MBARI scientists have worked together to document a unique seamount located about 20 miles (30 kilometers) off the coast of California’s Point Sur. With dramatic cliffs, winding coastal roads, and misty mountains, the landscape of Big Sur is captivating. Scientists and artists alike have long been fascinated by this place—and as Australian artist Francis McComas is famously quoted saying, it’s “the greatest meeting of land and sea in the world,” encapsulating its charm and grandeur.
While the undersea geological feature had been known via broad sonar mapping for decades, its biological significance was unmasked in 2013 during an expedition using MBARI’s remotely operated vehicle (ROV) Doc Ricketts. The discovery revealed that the beauty of Big Sur doesn’t end at the shoreline—it continues deep into Monterey Bay National Marine Sanctuary at this vibrant underwater mountain teeming with deep-sea life.
Sur Ridge rises 1,640 feet (500 meters) above the seafloor and stretches 11 miles (18 kilometers) long. Despite its massive size, its peaks are still more than 2,500 feet (762 meters) below the surface, where sunlight fades and a different kind of beauty takes hold. Here, delicate pink corals, ancient sponges, and other deep-sea creatures thrive on rocky slopes.
This area is one of 11 sanctuary ecologically significant areas within Monterey Bay National Marine Sanctuary. These selected spots highlight remarkable, representative, or sensitive marine habitats, and serve as priority sites for research and protection. Sur Ridge is a hotspot for biodiversity, supporting rich coral and sponge communities that provide essential habitat for a larger variety of marine life. In just one year, scientists using time-lapse cameras recorded 33 different types of large mobile animals, or megafauna, at a single site 4,035 feet (1,230 meters) deep—an impressive snapshot of the life that thrives far below the surface.
To understand how such richness is possible, researchers have turned to high-resolution seafloor mapping. These detailed images unveil a patchwork of cliffs, ridges, sediment plains, and coral forests revealing to us just how dynamic and diverse the deep ocean can be. Fine-scale mapping shows how subtle terrain shifts shape entire deep-sea communities. Together, these maps provide a blueprint for conservation and management, helping to safeguard not only coral “hotspots,” but the full mosaic of habitats that make the ridge extraordinary.
What makes Sur Ridge especially remarkable isn’t just its beauty—it’s the access it provides to science. Long-term monitoring is essential to understanding how ecosystems change, evaluating whether conservation and restoration efforts are working, and helping managers learn and adapt their decisions over time. Yet, this kind of repeated observation has historically been difficult in the deep sea where research requires specialized vessels, advanced technology, highly trained crews, and significant time and funding. As a result, most deep-sea coral ecosystems around the world are visited only once, offering scientists a brief snapshot before they must move on.
This offshore study area is within a three-hour boat ride of MBARI’s oceanographic research facilities located in Moss Landing. Utilizing their state-of-the-art research vessels and technologies, Sur Ridge can be explored again and again. This proximity has made the ridge a rare, natural underwater laboratory for tracking changes, coral restoration, and informing the management of deep-sea protected areas.
For more than a decade, MBARI and Monterey Bay National Marine Sanctuary collaborators have built an unmatched inventory of life at Sur Ridge and have since tracked changes in coral growth, species interactions, and environmental conditions year after year. This continuity allows researchers to go beyond one-time discoveries and instead piece together the bigger story of how deep-sea coral communities grow, adapt, and respond to changes.
Even after years of research, deep-sea corals still hold more questions than answers. Unlike their tropical relatives, we know little about how these corals reproduce: are they broadcast spawners or brooders? Do they follow seasonal cycles, or live by a rhythm all their own? Scientists also question whether colonies are male, female, or mixed. To unravel these mysteries, researchers are developing new ways to watch corals in their natural environment.
As MBARI senior scientist Jim Barry puts it, “Sur Ridge is becoming a deep-sea coral observatory.” It’s not just a place of discovery—it’s where the deep sea can tell its own story. With time-lapse cameras, current meters, particle traps, eDNA samplers, and marked corals, scientists can track changes continuously, learning how corals grow, feed, and interact with their environment across seasons and years. Protection for the observatory and restoration efforts are now facilitated by a 2026 NOAA Fisheries amendment to the Pacific Coast Groundfish Fishery Management Plan that designated Sur Ridge as a coral research and restoration area.
The observatory has also become a testing ground for deep-sea coral restoration. Before corals could be outplanted, researchers first needed to understand the stage on which these communities thrive. In a 2019 study, MBARI and Monterey Bay National Marine Sanctuary colleagues combined high-resolution multibeam mapping with ROV surveys to chart the seafloor and reveal the habitats supporting corals and sponges. They found a patchwork seascape from steep rock walls and boulder outcrops to soft sediment plains—each hosting its own community. For example, corals and sponges flourished on hard substrates, while sedimented areas supported different assemblages. Documenting even finer-scale habitat patterns, like rock type, provided the foundation for restoration, guiding experiments in outplanting corals back onto the ridge and turning ecological insight into conservation action.
Thanks to MBARI and NOAA’s Monterey Bay National Marine Sanctuary, Sur Ridge is now a model for using science to guide conservation in one of the ocean’s least understood environments. Fine-scale seafloor mapping, coral fragment outplants, and long-term monitoring are already shaping restoration techniques and mitigation strategies, helping vulnerable deep-sea communities recover and thrive. By treating Sur Ridge as a science hub, researchers are laying the groundwork for deep-sea conservation on a global scale. What we learn here—about growth, reproduction, and survival—will ripple far beyond Monterey Bay National Marine Sanctuary, helping to safeguard coral and sponge ecosystems wherever they’re found.
Sadie Gardiner is an undergraduate intern with NOAA’s Monterey Bay National Marine Sanctuary.
Maya Bañuelos is a graduate student intern with NOAA’s Monterey Bay National Marine Sanctuary.
Rachel Plunkett is the content manager and senior writer/editor for NOAA’s office of National Marine Sanctuaries
Raúl Nava is the senior science communication and media relations specialist at MBARI