Expedition Features: 2021 North Atlantic Stepping Stones: New England and Corner Rise Seamounts: NOAA Ocean Exploration

2021 North Atlantic Stepping Stones: New England and Corner Rise Seamounts (EX-21-04) expedition map with dive sites.

Mapping and remotely operated vehicle (ROV) operations yielded observations of numerous potential new species and new animal behaviors, geological samples to expand our understanding of ferromanganese crusts, data on 20 seamounts that had never been mapped before, and the engagement of audiences around the world.

Ferromanganese nodules collected from seamounts and abyssal plain nodules.

What’s In a Nodule?

During the recent 2021 North Atlantic Stepping Stones expedition, scientists discovered large fields of charismatic round rocks identified as ferromanganese nodules on two different regions of Gosnold Seamount. But what is a nodule?

Video Feature: A Hungry Sea Star

During Dive 11 of the 2021 North Atlantic Stepping Stones expeditions, scientists observed this sea star, Sthenaster emmae, feeding on a whip coral in the genus Calyptophora at a depth of 1,219 meters (4,000 feet).

Discovering and Annotating

During the 2021 North Atlantic Stepping Stones expedition, I participated as a scientist from shore with NOAA Ocean Exploration as part of my Ernest F. Hollings Scholarship Program internship this summer. This included participating through the science teleconference line and chat room.

Video Feature: Spongebob and Patrick

Video of a yellow sponge (genus Hertwigia) and pink sea star (genus Chondraster) collected during Dive 19 of the 2021 North Atlantic Stepping Stones expedition. Images of the pair have captured the attention of the public and the media due to their resemblance to the cartoon characters SpongeBob SquarePants and Patrick Star.

A Look Below the Seafloor With Sub-Bottom Profiler Data

Using the mapping tools on NOAA Ship Okeanos Explorer, data are collected to produce high-resolution bathymetric maps of the seafloor similar to topographic maps common for areas on land, but under water, to measure layers and currents in the water column, and to look below the seafloor to see what is hidden, even from the cameras of remotely operated vehicle Deep Discoverer.

National Intern Day 2021

At NOAA Ocean Exploration, a core part of our mission is engaging the next generation of ocean explorers through internships. As we celebrate National Intern Day 2021, get to know some of this year’s interns!

A colony of bamboo coral with crinoids on Mytilus Seamount, which is within both the Northeast Canyons and Seamounts Marine National Monument and the Georges Bank Deep-Sea Coral Protected Area. While exploring this area in 2013, researchers observed that corals were diverse, but their composition and abundance differed between the north and south side of the seamount.

NOAA’s Exploration and Research Efforts Inform Management Decisions for Deep-Sea Coral Communities

The data collected from NOAA’s deep-sea exploration and research efforts improve our scientific understanding of the diversity and distribution of deep-sea coral communities. It will also aid resource managers in developing and evaluating management options for these valuable habitats—on which U.S. fisheries and communities depend.

New bathymetry data of the New England Seamounts collected with the EM 304 MK II variant during the 2021 North Atlantic Stepping Stones: New England and Corner Rise Seamount Chain (EX-21-04) expedition, overlaid on the Global Multi-Resolution Topography Data Synthesis grid.

Mapping and Diving Go Together Like Peanut Butter and Jelly

You likely know that during remotely operated vehicle (ROV) expeditions there are two main operations occurring, generally ROV dives during the day and mapping the seafloor overnight. But did you know that these operations are strongly linked?

Seafloor data from the depths of the Atlantic to my home computer in California, delivered in near real time.

Sailing in the Cloud

As a geologist, I had written off working from home a long time ago, as most of my work depended on data collection in the field. 2020 really threw this dedicated and resilient team a challenge, and the solution to it was cloud-based mapping.

The Monument in Your Backyard

A mere 130 miles southeast of Cape Cod, Massachusetts, lies the Northeast Canyons and Seamounts Marine National Monument. One of just five marine national monuments — and the only one off the U.S. mainland — it protects an area of open ocean roughly the size of Connecticut.

The manipulator arm of remotely operated vehicle Deep Discoverer is used to clip a branch off a bamboo coral during Dive 02 of the 2021 North Atlantic Stepping Stones expedition. A small anemone was observed living on the coral, causing the coral to create small, basket-like branches around the anemone. The collected sample, once processed and made available to scientists, may help scientists better understand the relationship between the anemone and its coral host.

Shore-side Data Management of Deep-sea Specimens

In addition to high-definition video data and environmental parameters such as water temperature, salinity, dissolved oxygen, location, and depth, remotely operated vehicle Deep Discoverer collects highly valuable biological and geological specimen samples. Managing these physical samples from the depths of our ocean is high-priority work.

Video Feature: A Colorful Ctenophore

Belonging to the ctenophore order Lobata, family Lampoctenidae, this animal was initially identified as being the bloody belly ctenophore, though emerging research suggests that this yellow ctenophore might be a new and different red-belly ctenophore species.

We saw several oreo fish during our dives on the Corner Rise Seamounts. This one was imaged at 1,208 meters (3,963 feet) during Dive 11 of the 2021 North Atlantic Stepping Stones expedition.

Video Feature: It’s a Cookie … It’s a Fish … Meet the Seamount Oreos

“Oreo” is a common name for a group of deep-sea fishes in the family Oreostomatidae. Most species are found in the Southern Ocean on continental slopes and seamounts. Their body form and behavior suggest they could be at home on any shallow tropical coral reef.

During Dive 07, we had our first octopod sighting of the 2021 North Atlantic Stepping Stones expedition — a dumbo! Seen at 2,484 meters (8,150 feet), scientists believe that it is the rare species Cirrothauma magna.

Video Feature: Identifying a Strange Squid and a Dumbo Octopod on the “Stepping Stones”

First impressions are often speculative and are not necessarily the final answer. My first guesses at identification of an interesting squid and a cool octopod were (1) probably wrong and (2) definitely wrong. Not too far off, but not a bullseye either.

Map showing the bathymetric data collected around the Corner Rise Seamounts during the 2021 North Atlantic Stepping Stones expedition. Much of this area had not been mapped at all prior to the expedition, and in addition to providing critical information needed to successfully plan expedition dives, this mapping data contributes to our overall understanding of the seafloor.

Recap: Exploring the Corner Rise Seamounts

As we transition to our next set of dive sites on the New England Seamounts (mapping along the way, of course!), we asked our expedition team leads what was most interesting, most surprising, or aspect from which they learned the most during our eight dives on the Corner Rise Seamounts.

Video Feature: Cerianthid Anemone

Cerianthid or tube anemones, belonging to the subclass Ceriantharia, are rather distant relatives of sea anemones. All tube anemones have a quite uniform appearance, with an elongated body and two crowns of non-branched tentacles.

While exploring “Dumbbell” Seamount during Dive 04 of the 2021 North Atlantic Stepping Stones expedition, we observed several of these steep cliffs covered with a high diversity of sponges.

How Long Must I Wander?

We talk about seamount chains being stepping stones for organisms, about finding the same species along these chains and about the often-dense communities of deep-sea corals and sponges that live there. But how does that happen, when these animals can’t swim?

Sargassum is a genus of large brown seaweed (a type of algae) that floats in island-like masses. These floating rafts can stretch for miles across the ocean, serving as habitat that provides food, refuge, and breeding grounds for an array of animals such as fishes, sea turtles, marine birds, crabs, shrimp, and more.

The Importance of Exploring the Sargasso Sea: ‘Spiritual and Aesthetic Delight’ as Well as Conservation

The Sargasso Sea is a distinctive ecosystem located on the high seas. Its boundaries are defined by currents circulating the North Atlantic sub-tropical gyre, including the Gulf Stream and the Antilles Current. The Sargasso Sea is named for the floating sargassum that populates its surface – a kind of macroalgae that is designed for a pelagic (open ocean) existence, never attaching to the bottom at any point in its life cycle.

We caught a glimpse of this red crab hiding against a ferromanganese-encrusted boulder during 2014 exploration of Retriever Seamount.

Oh, (a Few of) the Places We’ll Go!

While most of our dives during this expedition will occur on seamounts that NOAA Ocean Exploration has not explored yet via NOAA Ship Okeanos Explorer, we will be revisiting a few familiar seamounts within the New England Seamount chain from dives in 2014 and 2019.

Diagram showing deepwater upwelling, caused by nutrient-rich bottom-water hitting the seamounts and circulating around them, and potential flow of larvae from one seamount to another.

Tiptoeing Through the North Atlantic

Some seamounts form long chains as the continental shelf glided over a hotspot in the Earth’s crust, creating seamounts one after another in a long succession stretching back over 100 million years. These seamount chains can form what we call “stepping stones” across the seafloor—areas of habitat that are suitable for a wide variety of species to settle, colonize, and live.

While exploring Gosnold Seamount in 2014, we encountered a high diversity of deep-sea corals and sponges, such as those shown here on a steep outcrop during our transit upslope. In addition to their interesting geological features, seamounts are also important because they harbor more marine life than the surrounding seafloor, often becoming isolated oases of life.

Geological History of the New England and Corner Rise Seamounts

The New England and Corner Rise seamount chains comprise a line of extinct submarine volcanoes that extend from near the Mid-Atlantic Ridge to the eastern continental margin of the United States.

Map showing the two seamount chains we will visit during this cruise - the New England and Corner Rise.

Expedition Plan

From June 30 through July 29, 2021, NOAA Ocean Exploration and partners will conduct the 2021 North Atlantic Stepping Stones: New England and Corner Rise Seamounts expedition, a telepresence-enabled ocean exploration expedition on NOAA Ship Okeanos Explorer to collect critical baseline information about unknown and poorly understood deepwater areas off the eastern U.S. coast and high seas.