UNCW Researcher, Colleagues to Assess Underwater Data from Gulf of Mexico
UNCW deep water corals researcher Steve Ross and his research colleagues, Sandra Brooke (UNCW adjunct faculty), Tara Casazza (UNCW research associate), and Mike Rhode (UNCW research associate), recently completed a cruise in the Gulf of Mexico on the R/V Tommy Munroe. The purpose of the cruise was to recover a benthic lander that was deployed near coral mounds during a separate research cruise one year ago. The lander, which was successfully retrieved, housed numerous instruments and experiments that will provide data related to the health of deepwater coral colonies and potential changes taking place due to both climate change and the Deepwater Horizon oil spill.
“Even though seas were rough that day, the recovery operation went smoothly,” said Ross. “We called the lander through an acoustic release, told it to drop a 600-pound weight, and it came right to the surface near the ship. Our experiments with living corals sent down in the lander were 100 percent successful, with all corals returning alive and showing growth. All other instruments and experiments appear to have worked completely.”
The lander was initially dropped to the floor of the Gulf in October 2010 during a cruise on the Greenpeace vessel Arctic Sunrise, the purpose of which was to investigate how the health of deep sea corals in the Gulf may have been impacted by oil from the Deepwater Horizon spill and dispersants used for cleanup. After it reached the bottom, the lander was found and photographed on the bottom by a research submersible, thus Ross and crew knew it was in a good position.
Ross noted that the successful recovery of the Lander will yield data that would otherwise be unattainable related to how deep sea corals are adapting to a rapidly changing environment. Findings will be compared to several years of baseline data previously collected from the same Gulf locations by Ross and Sandra Brooke, director of coral conservation at Marine Conservation Institute. The data may reveal damage to corals connected to the oil spill, and it will definitely reveal the degree of environmental variability experienced by the corals and other deep-sea organisms.
Ross noted that preliminary review of the data will take place in the near future, but final analysis and results may take some time. The data include monthly sediment trap samples, and data measured every 10 minutes for a year on temperature, salinity, turbidity, dissolved oxygen and bottom currents. Experiments included settling plates and coral growth and survival chambers.
Deep-sea coral reefs can reach several hundred feet above the seafloor, and are constructed by delicate branching deep-sea corals that provide habitat for an abundant and diverse community of marine life. Some deep-sea corals grow only millimeters per year, and deep-sea coral reefs can take thousands of years (maybe hundreds of thousands of years) to form.
“The health of these systems is directly linked to the health of the ocean,” Ross said. “We must learn how to protect them before our negligence causes their extinction.”
Dana Fischetti, Marketing and Communications, University of North Carolina Wilmington