Michael Carver, Operations Coordinator
Cordell Bank National Marine Sanctuary
Today’s weather conditions were calm with a light swell from the south. Following three successful days of marine debris removal it was time to move ahead on one of our secondary objectives, to dive on a shipwreck in Gulf of the Farallones National Marine Sanctuary (GFNMS). There are approximately 200 ships and aircraft reported lost in GFNMS. The shipwrecks are the result of significant maritime exploration and commerce, which historically occurred in the region, coupled with a foggy and rocky coastline.
Today would be the first day that Remotely Operated Vehicle (ROV) pilot Craig Bussel would relinquish the controls of the ROV, which he had been expertly piloting for days. Staff from the Cordell Bank National Marine Sanctuary were ready to pilot the ROV. First at the helm was Michael Carver. Dan Howard continued to skillfully manage the back deck, a role he had been filling on the cruise for several days. The deployment of the ROV went smoothly and the vehicle began swimming away from the boat. After a few minutes, the ROV had safely descended onto a flat sandy bottom with about 50’ of visibility. With the aid of our tracking system, we navigated the ROV towards the coordinates of the shipwreck given to us by the Office of National Marine Sanctuaries (ONMS) maritime heritage program. The shipwreck was discovered during a multibeam/side scan sonar survey completed by NOAA’s Office of Coast Survey in partnership with the National Park Service’s Submerged Resources Center in 2007.
Two views of shipwreck in Drake’s Bay: side scan sonar (left) and multibeam (right). Images produced from data collected by NOAA Ocean and Coast Survey vessel NRT-6 in October 2007. (Photo: NOAA’s Office of Ocean and Coast Survey)
Piloting the ROV around for several minutes, the Cordell Bank Sanctuary team saw nothing that looked like a shipwreck. Then, in the distance, there was a white-plumedanemone growing on what appeared to be a uniform sand-bottom. On closer inspection, the object it was growing on looked man-made. While continuing on the same bearing, the ROV team kept a sharp eye on the computer monitor that was displaying data from the ROV’s sound navigation and ranging (SONAR) unit. The active SONAR, which is fitted to the front of the ROV, uses echolocation to help the pilot see what is ahead. This system of echolocation is similar to that which is used by whales and dolphins to locate prey. After several minutes of nothing showing up on the SONAR screen, the display lit up with a bright yellow image that was, without question, the outline of a sunken ship.
Image of shipwreck as seen through ROV's SONAR. (Photo: Michael Carver/Cordell Bank National Marine Sanctuary)
Michael carefully moved the ROV closer to the wreck to get a better look. The first pass of the ROV showed the vessel had a steel hull that small schools of rockfish were using as habitat. Although the steel hull had experienced a high-level of degradation, there was still evidence of various parts of the ship.
After over an hour of gingerly maneuvering around the wreck it was time to take a break. Superintendent Dan Howard took a turn at the controls. Working carefully, so as not to disturb the wreck, the team logged almost 2 hours of video footage of the wreck. During the dive, the crew, with substantial help from Craig Bussel, identified numerous parts of the ship, including the diesel engine and windlass.
Video footage of shipwreck (including cylinder heads of a 3-cylinder diesel engine) and associated biological community. Click here to watch the video. (Video footage: Michael Carver/Cordell Bank National Marine Sanctuary)
To the best of our knowledge, this shipwreck has never been video documented. It was both surreal and thrilling to be part of a team that was the first to collect video footage of this ship. The ROV survey that CBNMS conducted will aid on-going historic research being conducted to help identify the mystery shipwreck as well as to assist GFNMS staff in managing and protecting the shipwreck.
Critical to the success of this dive, and all the dives at Cordell Bank, was the stability of the R/V Fulmar. ROV operations can be nearly impossible if the ship cannot remain above the ROV. Thanks to a great vessel and crew, we had another successful day of ROV operations off the R/V Fulmar.
A key mandate of the Office of National Marine Sanctuaries is to explore, characterize and protect submerged archaeological heritage resources and to share expedition discoveries with the public. To learn more about ONMS maritime heritage program visit http://sanctuaries.noaa.gov/maritime.