By Erik Cordes, Associate Professor, Temple University
Amanda Demopoulos, Research Benthic Ecologist, U.S. Geological Survey
Caitlin Adams, Web Coordinator, NOAA Office of Ocean Exploration and Research
From April 9 to 30, 2019, NOAA and partners at the Bureau of Ocean Energy Management (BOEM) and the U.S. Geological Survey (USGS) will conduct a research expedition on NOAA Ship Ronald H. Brown to collect critical baseline information about deepwater habitats offshore the U.S. Mid- and South Atlantic coasts. This expedition is part of the 4.5-year BOEM-USGS-NOAA Deep Sea Exploration and Research of Coral/Canyon/Cold seep Habitats (DEEP SEARCH) interagency project sponsored by the National Oceanographic Partnership Program (NOPP), with TDI-Brooks International, Inc. as the prime contractor for BOEM, and scientists from USGS and nine academic institutions participating. During this 22-day expedition, remotely operated vehicle (ROV) Jason will be used to explore and sample seafloor environments, complemented by additional shipboard operations including multibeam mapping, multicore collections, and CTD casts.
DEEP SEARCH’s primary goal is to augment the ability to predict the location of seafloor communities off the coast of the Southeast United States that are potentially sensitive to disturbance. This area encompasses a variety of different habitat types, including submarine canyons, cold-water coral mounds and gardens, methane seeps, and soft sediments. We will explore and characterize the biological communities of the study area; examine their sensitivity to natural and human disturbance; and describe the oceanographic, geological, geochemical, and acoustic conditions associated with each habitat type.
Deep-sea ecosystems along the U.S. continental margin support enhanced biodiversity and sensitive biological communities, yet they remain poorly understood. The maintenance of biodiversity is critical to the function and sustainability of these deepwater ecosystems that provide numerous ecosystem services. Loss of deep-sea biodiversity could have long-term, damaging effects to large expanses of the deep seafloor, the overlying water column, and to human health. Thus, we need to better understand these systems so they can be effectively managed. Through this study, we will improve our understanding of the habitats and communities in offshore areas of the Atlantic Large Marine Ecosystem, which will augment the capacity to predict the distribution of sensitive areas with respect to the potential development of energy and marine mineral resources.
This is the fifth research expedition associated with this project. The first was on NOAA Ship Pisces with the autonomous underwater vehicle (AUV) Sentry in September 2017. This cruise was heavily impacted by weather, but the team acquired some multibeam data and accomplished three Sentry dives in the study area. The second mission was originally scheduled on NOAA Ship Nancy Foster, but it was cancelled due to needed ship repairs. That mission was re-allocated to two cruises in 2018: multibeam mapping objectives were completed by during a cruise on NOAA Ship Okeanos Explorer in May 2018 and the sampling and lander component was conducted on the R/V Brooks McCall in October 2018.
The Okeanos Explorer cruise was highly successful and detailed bathymetry was acquired over the southern Lophelia coral portions of the study area. These locations were selected using a combination of prior coral observation data along with the results of our preliminary predictive habitat models. The subsequent Okeanos Explorer ROV mission, Windows to the Deep 2018, was co-led by DEEP SEARCH co-principal investigator Cheryl Morrison and included a number of exploratory dives to coral, canyon, and seep habitats in the DEEP SEARCH study area.
In August 2018, the DEEP SEARCH team completed a 15-day expedition on the Woods Hole Oceanographic Institution (WHOI) operated R/V Atlantis using human occupied vehicle (HOV) Alvin. Eleven dives were completed at three canyons, two seep sites, and four coral sites, ranging in depth from 403 to 2,169 meters (1,322 to 7,116 feet). Mapping data from the earlier Okeanos Explorer cruises were augmented with an additional 8,233 square kilometers (3,178 square miles) of data. Biological, geological, and chemical samples were collected by HOV Alvin and with CTD, monocore, and multicore instruments.
The 2019 expedition on board NOAA Ship Ronald H. Brown with the ROV Jason builds upon all of this work and will allow the DEEP SEARCH team to build upon the successes of the Atlantis cruise. The primary objectives of the 2019 cruise are as follows:
During the 22-day voyage in and out of Charleston, South Carolina, the team has planned for daily dives (see sampling map), including canyons and seeps located offshore Virginia and North Carolina and coral mounds recently mapped by Okeanos Explorer near the Georgia-Florida line.