The expanse of ocean between Georgia and Virginia is subtly amazing. From the surface, it appears to be just another expanse of dark Atlantic water, unremarkable, a little choppy in the fall, the kind of sea you fly over mindlessly. However, beneath it, coral forests, methane seeps, and ecosystems that scientists are just starting to comprehend stretch along the continental shelf and spill into deep submarine canyons. To begin assembling the picture, a fleet of research ships, federal robots, and almost five years of coordinated fieldwork were required.
DEEP SEARCH, which stands for Deep Sea Exploration to Advance Research on Coral, Canyon, and Cold Seep Habitats, is one of the most ambitious cooperative ocean science initiatives that the US government has undertaken recently. The study, which was started in 2017 as a collaboration between USGS, BOEM, and NOAA, sent researchers on five research cruises through some of the least-documented waters on the U.S. East Coast aboard ships like NOAA Ship Pisces and NOAA Ship Ronald H. Brown. Finding out what’s really living down there before decisions about offshore energy development made that question permanently moot was the simple, if logistically challenging, goal.
It was more difficult to predict what they discovered. In 2018, Lophelia pertusa, a stony cold-water coral that scientists were familiar with from the North Atlantic but hadn’t anticipated growing this deep or this far offshore, created massive reef structures that researchers using the human-occupied vehicle Alvin discovered. The reefs were dense, vibrant, and surprisingly large in some places. The Richardson Reef Complex, which is currently regarded as one of the biggest cold-water coral reefs ever discovered, eventually surfaced among the discoveries. It’s not a small footnote. The map is altered.
It’s difficult to ignore how much of this narrative depends on timing. The Bureau of Ocean Energy Management, or BOEM, was concurrently creating environmental review procedures that would require precisely the type of baseline data DEEP SEARCH was intended to produce, and the study was conceived during the height of discussions regarding Atlantic offshore oil and gas leasing. That overlap has a useful tension. It’s not always easy to sit with the familiar modern dynamic of science racing to document ecosystems before industrial decisions render the documentation academic.
Some of the program’s most striking images came from the 2019 expedition off the coasts of Georgia, South Carolina, and North Carolina. It turned out that the walls of Pamlico Canyon were covered in stony corals, octocorals, and brinsingid starfish, all of which were packed together in an almost theatrical manner. This density is more typical of tropical reefs than of icy, dark water 1,000 feet below the surface. Earlier, scientists found chemosynthetic tubeworms living at methane cold seeps about 36 miles off North Carolina in a detail that seemed almost cinematic. Vestimentiferan tubeworms. It was the species’ first known sighting in that region of the Atlantic. It turns out that the ocean had been hiding that specific information for a very long time.
The places where hydrogen sulfide, methane, and other hydrocarbons seep up through the seafloor and support communities of organisms that are completely independent of sunlight are known as cold seeps. They rely on chemistry rather than photosynthesis, which, despite repeated explanations, still seems a little unlikely. The known distribution of these environments along the U.S. East Coast has been greatly expanded by DEEP SEARCH, which identified numerous seep sites along the survey corridor.
In the end, the program produced a sizable body of baseline data, including maps, biological samples, sediment cores, and environmental DNA, which BOEM can now use to guide future decisions about where energy development might be compatible with sensitive ecosystems and where it most likely shouldn’t go. Although it’s still unclear how much institutional weight these findings will carry when they meet the economics of offshore leasing, that is a truly useful outcome. Policy is informed by science. The question of whether policy listens is a completely different one, and it usually receives a slow response.
