Sanctuary Integrated Monitoring Network
Monitoring Project

Exploration of Sur Ridge

Principal Investigator(s)

  • Jim Barry
    Monterey Bay Aquarium Research Institute
  • Andrew DeVogelaere
    Monterey Bay National Marine Sanctuary


  • NOAA
  • Save The Earth Foundation
Start Date: December 15, 2013

Sur Ridge is a rocky feature 28 miles offshore of Point Sur, California. The feature is 11 miles long and 3 miles wide, extending 817-1,569 meters beneath the sea surface. Exploration of Sur Ridge began December 15, 2013 during a larger research cruise to revisit a lost shipping container. Using the research vessel Western Flyer and ROV Doc Ricketts, we completed two exploratory ROV dives on Sur Ridge. We targeted high slope and ridged areas at the northern and southern parts of Sur Ridge. Corals and sponges were found to be abundant and diverse.

Project objectives include: 1) exploration; 2) general characterization; 3) quantifying megafaunal distributions in relation to substratum characteristics; 4) collecting bamboo corals to estimate age and to determine productivity changes in the California Current over time; 5) marking selected coral/sponge locations for monitoring growth rates; 6) testing how corals defend themselves from predation by sea stars; and 7) developing transplant and restoration techniques for deep-water corals.

To date, we have surveyed Sur Ridge during December 2013, June and July 2014, and June 2016.

Summary to Date

Corals and sponges were found to be abundant at Sur Ridge, particularly bamboo corals. Brooding octopi and a cold-seep were also documented. “Sweeper tentacles” on bamboo corals are effective at deterring sea star predation.

Monitoring Trends

  • No trends until project data are analyzed and summarized.


No discussion until project data are analyzed and summarized.

Study Parameters

  • Habitat association
  • Diversity
  • Distribution

Study Methods

Habitat and Species Analyses

To document habitat and species occurrence at the Sur Ridge, HD video was continuously recorded. During each ROV Doc Ricketts dive, video frame grabs were recorded and preliminarily annotated using MBARI’s computer video annotation program, VARS (Video Annotation and Reference System). Several video sampling methods were used to characterize the Seamount: 1) video transects; 2) video frame grabs; and 3) general observation video footage. Transect length and duration depended on dive objectives and suitable habitat for ROV operation. General observation video footage was used to explore the area, and recorded during collection of animals. Transects and frame grabs will be used to quantify habitat and macrofauna.

Figures and Images

Figure 1. Sur Ridge was a relatively unexplored 800 meter tall hill, about the size of the island of Manhattan, on the seafloor within Monterey Bay National Marine Sanctuary until MBARI and MBNMS explored it with a deep-sea remotely operated vehicle (ROV) in December 2013. Significant deep-sea coral and sponge communities were discovered, which prompted return expeditions in June and July 2014 and June 2016, of which all ROV dives are plotted here, colored differently by year. Data from MBARI (courtesy of David Clague).

Figure 2. A three-dimensional view of Sur Ridge from the southwest. Color indicates a depth change maximum of approximately 800 meters. The scene is vertically exaggerated by a factor of 2. Data from MBARI (courtesy of David Clague).

Figure 3. A colorful collage of some of the incredible sights from ROV dives on Sur Ridge, which included more than 10 species of coral, many different sponges, two blob sculpins, nudibranchs, brooding octopii, dozens of other cnidarians all on a landscape of ever-changing and diverse habitat.

Figure 4. Snailfish (Family: Liparidae) rests inside of a sponge near the summit of Sur Ridge.

Figure 5. Bamboo coral (Isidella tentaculum) is an upright branching soft coral that acts as a foundation species for other benthic megafauna.

Figure 6. Left: Bamboo coral (Isidella tentaculum) and marker to monitor growth rates. Right: Bubble gum coral (Paragorgia arborea) and experimental PVC transplant device.

Figure 7. Vesicomyid clam and cold seep at Sur Ridge.

Figure 8. Sea star upon sweeper tentacles of Bamboo coral (Isidella sp.).

Figure 9. Octopus at Sur Ridge.

Figure 10. Close-up of octopus arms and egg cases at Sur Ridge.

Figure 11. Giant Grenadier (Albatrossia pectoralis).