Revealing the secrets of Sur Ridge

During this special event on Wednesday, June 30, 2021 at 11:00 a.m. (Pacific), audiences dove behind the scenes of MBARI’s expedition to Sur Ridge during our inaugural Live from the Deep virtual event. Watch the recording here to see stunning footage of the deep seafloor, hear from experts at MBARI, Monterey Bay National Marine Sanctuary, and Monterey Bay Aquarium, and find out what it’s really like to have a career exploring the deep ocean. Learn more.

About Sur Ridge

Many mysteries persist in the ocean’s depths, but MBARI’s pioneering technology is revealing secrets in these midnight waters. Using a suite of mapping instruments, MBARI is shedding new light on Sur Ridge, a large underwater geologic feature located about 60 kilometers (37 miles) from Monterey and 30 kilometers (19 miles) off Point Sur. This rocky ridge rises 500 meters (1,640 feet) above the seafloor and is a hotspot for marine life.

The jagged rocky surface of Sur Ridge supports an abundance of corals and sponges, which in turn provide refuge for countless fishes and invertebrates.

In December 2013, researchers from MBARI and the National Oceanic and Atmospheric Administration (NOAA) embarked on a six-day research cruise to document life on the floor of Monterey Canyon. The team found themselves ahead of schedule and opted to venture further down the coast to survey Sur Ridge, an area of the seafloor largely unstudied at the time. As MBARI’s remotely operated vehicle (ROV) Doc Ricketts approached, its cameras revealed lush gardens of corals and sponges atop the rugged ridge.

Subsequent trips have allowed MBARI researchers to deploy a variety of tools to better our understanding of Sur Ridge. This site is relatively close to shore and serves as a model for studying deep-water seamount ecosystems. Thousands of seamounts arise from the floor of the Pacific Ocean, but most are poorly studied.

The corals and sponges growing on Sur Ridge offer shelter and refuge for countless creatures. This long-armed crab (Sternostylus iaspis) precariously perches on a coral. Its long arms extend the reach of its claws to grab food drifting by in the currents. Learn more about the long-armed crab. Image: © 2016 MBARI

Sur Ridge bears many similarities to Davidson Seamount located to the southwest. While smaller in size and closer to shore, Sur Ridge is home to many of the same species, like enormous, knobby corals and vase-like sponges. Both Sur Ridge and Davidson Seamount are oases of life compared to the flat, muddy plains surrounding them, and both are vulnerable to impacts from humans, including fishing pressure and climate change.

Over the last two decades, Sur Ridge and Davidson Seamount have been regular targets of MBARI expeditions, often in close collaboration with scientists from the Monterey Bay National Marine Sanctuary. MBARI’s research proved instrumental in raising public awareness of the thriving, yet fragile, coral communities on Davidson Seamount. Thanks to public support, in 2008 the sanctuary’s boundaries were expanded to protect Davidson Seamount. Sur Ridge is already protected by the sanctuary, but by visualizing its grandeur in great detail, we hope to inspire a new generation of ocean stewards to explore—and protect—other treasures still waiting to be found in the deep sea.

Sur Ridge is located about 30 kilometers (19 miles) west of Point Sur on California‘s Central Coast. This map presents ship-collected EM300 multibeam sonar data at 30-meter resolution superimposed over a model of predicted bathymetry based on ship-collected depth data or, when not available, on satellite altimetry. Image: Jenny Paduan © MBARI 2021.

WARNING: This video may potentially trigger photosensitivity reactions. Viewer discretion is advised.

Data collected by MBARI’s mapping team has helped bring Sur Ridge to life. This animation combines data from ship-based multibeam sonar at 25 meters (82 feet) in resolution, autonomous underwater vehicle (AUV) multibeam mapping data at one meter (about three feet) in resolution, and remotely operated vehicle (ROV) mapping lidar data at five centimeters (two inches) in resolution. MBARI scientists worked with Los Angeles film production company Frame 48 to visualize the terrain of Sur Ridge in astonishing detail. Learn more.

Quick facts about Sur Ridge

  • Sur Ridge is over 20 kilometers (12 miles) long.
  • At its widest point, Sur Ridge is about four kilometers (2.5 miles) across.
  • Sur Ridge has peaks and valleys, but stands 500 meters (1,640 feet) tall.
  • More than 260 species of fishes and invertebrates have been found on and above Sur Ridge.

Sur Ridge is 30 kilometers (19 miles) west of Point Sur. This rocky ridge is about 60 kilometers (37 miles) from Monterey.

With its jagged topography, Sur Ridge’s rocky peaks are located 800 to 1,300 meters (2,600 to 4,300 feet) beneath the ocean’s surface.

Sur Ridge is over 20 kilometers (12 miles) long and four kilometers (2.5 miles) wide. It’s roughly the same size as Manhattan.

Sur Ridge rises 500 meters (1,640 feet) above the seafloor. Because Sur Ridge is nestled on the continental slope, measuring its height relative to the surrounding seafloor can be misleading—the ridge has a larger relative height on its downslope side—so MBARI typically measures the depths of the ridge’s four peaks instead. Sur Ridge’s highest point is the central peak and is 788 meters (2,585 feet) deep. The southernmost peak is 795 meters (2,608 feet) deep, while Sur Ridge’s two northern peaks are 825 meters (2,707 feet) and 857 meters (2,812 feet) deep.

MBARI leveraged a variety of platforms including ship-based multibeam sonar, autonomous underwater vehicles (AUVs), and remotely operated vehicles (ROVs) to map Sur Ridge.

Autonomous underwater vehicles (AUVs) use numerous narrow beams of sound to map wide swaths of the seafloor.

Remotely operated vehicles (ROVs) outfitted with MBARI’s groundbreaking Low-Altitude Survey System (LASS) use sound, light, and stereo photography to map the seafloor in incredible detail.


Upper-ocean systems
Acoustical ocean ecology
Acoustic instruments
Acoustic fingerprinting
Acoustic community ecology
Acoustics in the news
Biological oceanography
Global modes of sea surface temperature
Krill hotspots in the California Current
Nitrate supply estimates in upwelling systems
Chemical sensors
Chemical data
Land/Ocean Biogeochemical Observatory in Elkhorn Slough
Listing of floats
SOCCOM float visualization
Periodic table of elements in the ocean
Biogeochemical-Argo Report
Profiling float
Interdisciplinary field experiments
Ecogenomic Sensing
Genomic sensors
Field experiments
Harmful algal blooms (HABs)
Water quality
Environmental Sample Processor (ESP)
ESP Web Portal
In the news
Ocean observing system
Midwater research
Midwater ecology
Deep-sea squids and octopuses
Food web dynamics
Midwater time series
Respiration studies
Zooplankton biodiversity
Seafloor processes
Revealing the secrets of Sur Ridge
Exploring Sur Ridge’s coral gardens
Life at Sur Ridge
Mapping Sur Ridge
Biology and ecology
Effects of humans
Ocean acidification, warming, deoxygenation
Lost shipping container study
Effects of upwelling
Faunal patterns
Previous research
Technology development
High-CO2 / low-pH ocean
Benthic respirometer system
Climate change in extreme environments
Station M: A long-term observatory on the abyssal seafloor
Station M long-term time series
Monitoring instrumentation suite
Sargasso Sea research
Antarctic research
Geological changes
Arctic Shelf Edge
Continental Margins and Canyon Dynamics
Coordinated Canyon Experiment
CCE instruments
CCE repeat mapping data
Monterey Canyon: A Grand Canyon beneath the waves
Submarine volcanoes
Mid-ocean ridges
Magmatic processes
Volcanic processes
Explosive eruptions
Hydrothermal systems
Back arc spreading ridges
Near-ridge seamounts
Continental margin seamounts
Non-hot-spot linear chains
Eclectic seamounts topics
Margin processes
Hydrates and seeps
California borderland
Hot spot research
Hot-spot plumes
Magmatic processes
Volcanic processes
Explosive eruptions
Volcanic hazards
Hydrothermal systems
Flexural arch
Coral reefs
ReefGrow software
Eclectic topics
Submarine volcanism cruises
Volcanoes resources
Areas of study
Bioluminescence: Living light in the deep sea
Microscopic biology research
Open ocean biology research
Seafloor biology research
Automated chemical sensors
Methane in the seafloor
Volcanoes and seamounts
Hydrothermal vents
Methane in the seafloor
Submarine canyons
Earthquakes and landslides
Ocean acidification
Physical oceanography and climate change
Ocean circulation and algal blooms
Ocean cycles and climate change
Past research
Molecular ecology
Molecular systematics
SIMZ Project
Bone-eating worms
Gene flow and dispersal
Molecular-ecology expeditions
Ocean chemistry of greenhouse gases
Emerging science of a high CO2/low pH ocean


James Barry

James Barry

Senior Scientist & Benthic Ecologist


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