Deep-Sea Coral and Sponge Community Observatory at Sur Ridge

pink, yellow, and white branching organisms grow from a rocky surface in a dark ocean habitat with a crab and small sea star
Deep-sea coral, sponge, and crab community at Sur Ridge. Photo: MBARI

Sur Ridge is a rocky, deep-sea feature located 28 miles (45.1 kilometers) off the coast of Central California that supports deep-sea corals and sponges. It is 11 miles (17.7 kilometers) long and 3 miles (4.8 kilometers) wide, extending 2,680 to 5,148 feet (817 to 1,569 meters) beneath the sea surface. Since 2013, Monterey Bay National Marine Sanctuary and the Monterey Bay Aquarium Research Institute have partnered to explore and study this remarkable underwater oasis, and to better understand the impacts of climate change on the lush corals and sponges living there. Sur Ridge is a Sanctuary Ecologically Significant Area (SESA).

Beautiful and fragile, deep-sea corals can take hundreds of years to grow to full size. They provide habitat for other species and are an important indicator of critical habitat to protect from human disturbances. Basic understanding of deep-sea coral biology is important, as the deep waters off of Central California have a naturally low pH, and therefore will experience early ocean acidification—a phenomenon that is already being measured.

Map of Sur Ridge location
Sur Ridge, roughly the size of Manhattan, is relatively close to shore and serves as a model for studying deep-water seamount ecosystems.

Working aboard Monterey Bay Aquarium Research Institute’s research vessels, scientists use a suite of state-of-the-art marine technology, including cameras, high-resolution mapping tools, and remotely operated vehicles. Repeat visits to Sur Ridge have allowed scientists to enlist different technologies to monitor the coral communities as part of the Deep-Sea Coral and Sponge Community Observatory project.

A major component of this partnership is developing methods to restore coral communities after they have been eliminated. Together we have accomplished the following:

  • Located abundant and healthy deep-sea coral populations
  • Developed methods to revisit and track individual corals at depths greater than 4,000 feet
  • Begun understanding environmental and biological requirements for coral settlement and growth
  • Identified areas that have been damaged and are in need of coral restoration
  • Developed a technique to successfully
    • collect small branches from healthy corals (5 species);
    • transport coral branches to the surface;
    • place them in innovative cement “vases”;
    • and return corals to the deep (where many survived for a decade).

In addition, Sur Ridge research was used to inform development of the Monterey Bay Aquarium deep-sea exhibit, and was the subject of live-link education efforts.