This deep-sea octopus wants to wish you a happy Valentine’s Day on behalf of the OOI Regional Cabled Array team! ❤️ 🌊🚢🧪

Feeding frenzy! A swarm of hagfish tear apart a N Pacific Frostfish (?) at Hydrate Ridge offshore of OR. They look like eels but evolved ~550 million years ago, before sharks and bony fish! 🌊🚢🧪 PC: UW/NSF-OOI/WHOI, J-1719, V25; thanks to Dr. Brian Sidlauskas (Tulane) for the tentative carcass ID!

The Inferno edifice in the ASHES hydrothermal vent field in 2025. Superheated fluids streaming out of the chimneys contain dissolved gases and metals used by microbes within chemosynthetic organisms, which can completely encase sensors faster than you’d expect! PC: UW/NSF-OOI/WHOI, J-1707, V25 🌊🚢🧪

Fried Egg or “Egg-Yolk” jelly seen by the ROV Jason at Axial Base. These large jellyfish feed on other jellies and inverts at deep-water sites, and other species often live on or around them for protection. 🌊🚢🧪 More videos: www.youtube.com/@interactive... PC: UW/NSF-OOI/WHOI: J-1709, V25

R/V Atlantis SSSG Allison Heater helps V’25 student Nate Bodensteiner and RCA scientist Joe Duprey cock Niskin bottles for water sampling at Axial Seamount (2600 m depth). Analyses of the recovered fluids help verify data from the RCA moorings and seafloor sensors. 🌊🚢🧪 PC: M. Elend, UW, V25

Two roughtail skates sit in the mud among carbonate rubble at Southern Hydrate Ridge. These shark relatives are often seen lying partially buried on the seafloor at productive sites like this, where their prey (shellfish, worms, and small fish) are abundant. 🌊🚢🧪 PC: UW/NSF-OOI/WHOI, J2-1715, V25

VISIONS students help tech Alex Rose (2nd from left) prep a “Mosquito” instrument. It injects dye into the seafloor at Southern Hydrate Ridge then sucks fluid into coiled tubes to measure sediment seawater flow. It's complicated to assemble so more hands are always helpful! 🌊🚢🧪 PC: M. Elend, UW, V24

One month in a minute and a half! Enjoy this video highlight reel from our 2025 OOI-RCA maintenance cruise, and check out our YouTube channel (www.youtube.com/@interactive...) for more underwater video and sea life highlights. Happy Holidays! 🌊🚢🧪

A lava "whirlpool" formed during the 2011 Axial Seamount eruption and frozen in time. When subsurface magma erupts onto the seafloor as 1200°C lava, it hits near-freezing seawater and crusts over with a layer of glass, forming incredible river-like shapes! 🌊🚢🧪 PC: UW/NSF/OOI/WHOI; J2-1737, V25.

VISIONS'25 student technicians Alex Rose and Emily Pinneo help sample diffuse fluids entrained in a recovered osmosampler from the ASHES hydrothermal field. The samples provide a year-long record of hydrothermal fluid composition. 🌊🚢🧪 PC: M. Elend, University of Washington, V25

Crustacean love! Two Dungeness crabs we encountered in a mating posture during a dive at the Oregon Shelf (80 m) site. PC: UW/NSF/OOI/WHOI, J2-1742, V25. 🌊🚢🧪

UW RCA student worker Jolee Thirtyacre and one of our VISIONS’25 students assisting with CTD water sample processing. VISIONS students experience life at sea, stand ROV watches, and assist with many aspects of science conducted onboard the ship. 🌊🚢🧪 PC: M. Elend, University of Washington, V25.

On October 24, 2025 the RCA team participated in One Ocean Week Seattle aboard the historic sailing ship Statsraad Lehmkuhl from Bergen, Norway! Over 200 people came to view poster presentations and demonstration tables-ours included! 🌊🚢🧪

ROV video of an absolute mob of sablefish (black cod) swirling around the OOI-RCA benthic experiment package (BEP) at our Oregon Offshore site, about 40 miles offshore and 582 m deep. The yellow frame contains 8 different cabled oceanographic sensors. Credit: UW/NSF-OOI/WHOI, J2-1741, V25 🌊🧪🚢

The UW-RCA group just spent about a week turning OOI equipment at Axial Seamount, an active volcano about 200 miles off the Oregon coast. The seafloor in the caldera is covered with fantastic basalt formations, hydrothermal flows, and unique biological communities. 🌊🧪🚢

The OOI-RCA cruise has been conducting multiple dives at Axial Seamount (an underwater volcano off the Oregon coast), including deployments at several different hydrothermal vent fields. The weather has been excellent for ROV operations - hopefully that will hold for the next few days!

We visited Southern Hydrate Ridge earlier in the cruise, a dynamic site with active methane venting, exposed gas hydrate (methane ice!), and a diverse biological community - including rockfish, skates, and scavenging hagfish swarming around a sablefish carcass! 🌊🚢🧪

The OOI-RCA Shallow Profiler mooring platforms sit at 200 meters depth, over time becoming midwater islands of biodiversity as organisms like feather stars and nudibranchs settle on the hard surfaces of the flotation and instrument housings. 🌊🚢🧪

Since 2013, the VISIONS program has allowed more than 260 students to participate in at-sea experiential learning. This year we have 11 excellent students sailing with us as part of the UW’s educational mission (VISIONS’25), along with UW student technicians who are integral to the work of the RCA.

The 11th O&M Expedition for the cabled component of the NSF-OOI has begun, 7/31 - 8/31/2025! Live video from the R/V Atlantis & Jason ROV can be seen here: interactiveoceans.washington.edu/visions25-li... 🌊🧪🚢 PC 1: J. Tilley, UW-APL, V25. PC 2: M. Elend, University of Washington, V25

Learn about the most instrumented underwater volcano in the world, and the work being done by the NSF-funded Ocean Observatories Initiative, on the front page of CNN today. We'll be heading out to visit Axial Seamount this summer, so stay tuned! www.cnn.com/2025/05/08/s...

Welcome to the NSF-funded OOI Regional Cabled Array Bluesky account! Follow along for never-before-seen photos and ocean science content 🌊🧪🚢 For more from OOI Regional Cabled Array Cruises: interactiveoceans.washington.edu/images-visio...