Expedition goal: During this 10-day expedition aboard MBARI’s flagship research vessel David Packard, MBARI’s Benthic Biology and Ecology Team and collaborators from NOAA’s Monterey Bay National Marine Sanctuary will use a suite of diverse technologies to better understand the remarkable communities of life thriving on underwater mountains.

Expedition dates: August 3–12, 2026

Ship: R/V David Packard

Location: Davidson Seamount, Sur Ridge, Octopus Garden

Research technology: Benthic elevator, Benthic Respirometer System (BRS), CTD rosette, EK80 echosounder, FIDO eDNA sampler, free-vehicle Mega Coral Cam, hydrophone mooring, McLane Profiler, ROV Doc Ricketts, sediment trap mooring, Smith time-lapse cameras

Chief scientist: Jim Barry

Two large, branched pink corals grow on a greenish-black rocky outcropping on the deep seafloor. In the background are smaller pink and yellow corals that fade into black water.
Sur Ridge (pictured) and Davidson Seamount teem with life, including a variety of coral species, such as large bubblegum corals (Paragorgia arborea, pictured) and bamboo corals (family Keratoisididae). Image: © 2022 MBARI

Seamounts are underwater mountains that rise from the deep seafloor. They deflect ocean currents, concentrating nutrients and food to support thriving communities of life. Corals and sponges prosper on the rocky slopes of many seamounts, providing shelter for countless fishes and invertebrates, while large sharks, fishes, and marine mammals may find a feast in the waters above a seamount’s crest.

MBARI’s Benthic Biology and Ecology Team has conducted extensive research at two seamounts offshore of Central California: Sur Ridge and Davidson Seamount. MBARI makes our research, technology, and data available to resource managers and policymakers to guide decision-making about marine life, ecosystems, and resources. Our collaboration with NOAA’s Monterey Bay National Marine Sanctuary was instrumental in establishing protections for both Sur Ridge and Davidson Seamount. We continue to work with NOAA researchers to study these unique biological hotspots.

The Seamount Hotspots: Sur Ridge and Davidson Seamount Ecology Expedition will advance our research on coral communities, brooding deep-sea octopus, and puzzling scars in the seabed two miles beneath the surface, in support of three ecology projects.

A large scientific instrument sits on the silver deck of a ship on a sunny day. The instrument has a silver metal rectangular frame with an orange float at the top and several clear plastic chambers on the side. In the background is blue ocean with clear blue sky on the horizon.
The team will use the Benthic Respirometer System (BRS) to study the metabolic rates of deep-sea corals to better understand their resilience to changing ocean conditions. Image: Olívia Soares Pereira © 2025 MBARI

Sur Ridge is a rocky ridge approximately 32 kilometers (20 miles) offshore of Big Sur. Our studies here focus on factors that affect the success of deep-sea coral and sponge gardens 800–1,300 meters (2,600–4,200 feet) underwater. This expedition will help us better understand how sensitive deep-sea corals are to the effects of climate change. 

We plan to deploy our Benthic Respirometer System, an innovative instrument developed by MBARI engineers to measure the metabolism of seafloor animals in their natural environment. We will launch the BRS from R/V David Packard and let it sink to the bottom. We will then use the remotely operated vehicle (ROV) Doc Ricketts to place small coral colony branches into respiration chambers to measure their metabolic rates under manipulated low- and high-oxygen conditions. Related studies will involve the deployment of long-term oceanographic instruments—sediment traps and sensor packages—to measure the input of food sinking from surface waters throughout the year, as well as changes in temperature and oxygen levels.

A time-lapse camera in a silver metal and white plastic housing with green cables sits on the greenish-black, rocky seafloor observing an aggregation of nesting octopus on the left side of the frame. The round, pale purple octopus are clustered in a large rocky crevice. A second, smaller aggregation of nesting octopus is on the right side of the frame, behind the camera.
Time-lapse cameras will help MBARI researchers better understand life at Octopus Garden, including seasonal trends in nesting behavior. Image: © 2022 MBARI

Thousands of pearl octopus (Muusoctopus robustus) gather to nest in warm geothermal springs near the base of Davidson Seamount offshore of Central California. Known as Octopus Garden, this is the largest known aggregation of octopus in the world, with over 6,000 nests. MBARI and a team of collaborators have conducted extensive research at this site, chronicling the breeding habits of deep-sea octopus over several years. 

During this expedition, we are planning to deploy a time-lapse camera system to capture images of a small patch of approximately 50 brooding octopus mothers every 30 minutes or so over the next year. The observations will tell us more about the pace of life in this octopus nursery, from egg-laying to hatching. All octopuses die after breeding, and their tissues become part of the local food web. We will also measure the importance of octopus tissue as a food subsidy for the biodiversity and productivity of the local faunal community at Octopus Garden.

The Davidson Seamount Hotspot Project is a new research collaboration with MBARI’s Benthic Biology and Ecology, Acoustic Ocean Ecology, and Ocean Soundscape teams that aims to measure the potential role of the seamount in enhancing the productivity and feeding of beaked whales, especially the goose-beaked whale (Ziphius cavirostris).

A submersible outside of frame illuminates a large crater in a large expanse of brown muddy seafloor.
Scientists suspect pits in the sediment near Davidson Seamount may be created by beaked whales feeding in the area. Hydrophone moorings will allow MBARI researchers to listen for the distinctive vocalizations of these elusive whales. Image: © 2020 MBARI

We have observed puzzling pits in the seabed approximately two miles beneath the surface near Davidson Seamount. Similar features observed on the seafloor in other parts of the world are thought to be created by foraging beaked whales. These pits seem more abundant near Davidson Seamount than in other areas. 

During the expedition, we will deploy various instruments to assess the abundance of beaked whales that may be feeding near Davidson Seamount, and their prey. We will deploy hydrophone moorings at four sites—two near Davidson Seamount and two at more distant sites—to continuously record sound over the next year, so that we may detect the foraging clicks from beaked whales. We will explore the seabed in these areas during dives with ROV Doc Ricketts and sample water for eDNA analyses in hopes of detecting goose-beaked whales and their key prey species. Baited time-lapse cameras and acoustic surveys from the ship will also be used to assess differences in prey diversity and abundance among sites.

Together, the activities planned for this 10-day cruise will help us understand more about the rich and complex deep-sea communities that thrive in our backyard.

Expedition Logs

Team

Directory

Onboard Collaborators

Andrew DeVogelaere – NOAA

Shore Team

Shore Collaborators

Erica Burton – NOAA
Izzy Farrar – MBARI Summer Intern, Northern Arizona University
Chad King – NOAA
Astrid Leitner – Oregon State University

Marine Operations Team

Relief Crew

Justin Blair
Bernadette Castner

Technologies

All Technologies