Lophelia II: Reefs, Rigs, and Wrecks (MMS and NOAA OER)
Cruise Summary: August 19 –September 12, 2009
R/V Ron Brown, ROV Jason II
NOAA Ocean Explorer
There were a number of significant discoveries on this year’s cruise. We made a total of 17 dives at 13 natural sites, 8 of which had never had visual surveys before. Even with this high degree of pure exploration, we found corals at every one of the sites, and new high-density Lophelia pertusa communities at three of the sites. These included Garden Banks 535, the western-most Lophelia site in the Gulf; Viosca Knoll 906, one of the largest continuous Lophelia reefs known in the Gulf and named Roberts’ Reef; and a new area of Viosca Knoll 826, a 200 m long ridge hosting a large Lophelia reef. At Mississippi Canyon 751, we investigated the most active seep known to host live Lophelia colonies, which were quite abundant. We also found some high density black coral communities at a number of the sites we investigated, and a new site with a high abundance of bamboo corals at the northern end of the Florida Escarpment. This site in DeSoto Canyon was a new depth record for six different genera of octocorals including three different species of bamboo corals. We also collected the first alkalinity data from the deep Gulf of Mexico, which will guide our research into the potential impact of ocean acidification on deep-water corals throughout the rest of the project.