Monday, November 10, 2003

Media Contacts

Dr. Steven Miller 305-451-0233, Director, NURC/UNCW

Mark Ward 407-254-0840, NURC Public Affairs

Key Largo, Fl. - The last Aquarius science mission of 2003 begins Nov. 10 with a six-person crew led by principal investigator, Dr. Mark Hay of the Georgia Institute of Technology. He is joined by Alex Chequer, research scientist, Dr. Todd Barsby, post-doctoral researcher, and Deron Burkepile, Ph.D. student, all of the School of Biology at the Georgia Institute of Technology in Atlanta. UNCW habitat technicians include Mark Hulsbeck and Thor Dunmire, who provide operational support inside Aquarius for the mission. This will be Hulsbeck’s ninth saturation mission and Dunmire’s sixth. The Aquarius program maintains a pristine safety record.

Hay’s team will use their experience in marine ecology and chemical ecology to investigate how grazers, specifically parrotfish and surgeonfish, affect seaweeds and corals in the Florida Keys National Marine Sanctuary. Using Aquarius gives Hay and his colleagues an ideal platform from which to set up their experiments and to make observations. Said Hay, “Twenty years ago I used an underwater lab called Hydrolab (the predecessor to Aquarius) to discover how some seaweeds escaped and deterred herbivores (animals that eat plants) by a combination of growing at night and producing toxic chemicals. Aquarius will allow us to live on the ocean floor and be more constantly connected with our favorite marine system than any other humans on earth. Who could ask for more?”

Owned by the National Oceanic and Atmospheric Administration (NOAA) and operated by UNCW, Aquarius is a unique national asset - it is the only undersea research platform of its kind in the world. It rests in a sand patch surrounded by coral reefs, 63 feet deep, and 3.5 miles offshore at Conch Reef. Aquarius "aquanauts" live and work on the seafloor for extended periods using a special SCUBA diving technique called saturation diving that provides nearly unlimited bottom time to conduct scientific studies. Dr. Steven Miller, director of the National Undersea Research Center at UNCW, said, “We’ve had a successful mission year in 2003 and we are excited to see things wrap up with such an important project. We’ve been aware for a long time that fish grazing on coral reefs is important, but few details are known. The Hay group is well positioned to unlock some secrets.”

At first glance, seaweeds appear to be ripe food items for grazing fishes, but looks can be deceiving. Many seaweeds produce chemicals or they construct hard calcium carbonate skeletons that provide protection from grazing. The chemicals make the seaweeds taste bad and can produce dramatic effects on the survival, growth and reproduction of herbivores. Hard calcium carbonate skeletons can either make it difficult to take bites or the mineral can disrupt fish digestion. Thus, many seaweeds can protect themselves in an environment where abundant grazers represent a nearly constant threat. Hay added, “Herbivory on undisturbed coral reefs is more intense than in any other habitat; time-lapse movies have shown that fishes may bite small areas of the bottom more than 100,000 times a day. The seaweeds that persist in the face of this tremendous grazing pressure are among the best defended of all plants.” During this month’s Aquarius mission, experiments will be conducted to determine if common species of grazing fishes remove certain types of seaweeds from reef habitats, or if certain mixes of grazing species (some resistant to chemical defenses and others resistant to calcification) are critical to prevent seaweeds from overgrowing corals. If ecologically important herbivores differ considerably in their responses to seaweed defenses, then particular herbivores, or mixes of herbivores, could be crucial to maintaining ecosystem function by preventing seaweeds from overgrowing corals – with obvious management implications too.

During each Aquarius mission, anyone with Internet access can watch live Web cameras, read expedition journals from the aquanauts, view project summaries and pictures, and much more at the NURC/UNCW Aquarius Web site: www.uncw.edu/aquarius. Also during this mission, two outreach events will take place. First, at 10 a.m., Wednesday, Nov. 12, a live interactive session will be conducted between aquanauts working in Aquarius and participants at the Randall Library of UNC Wilmington. Then on Thursday, Nov. 13 another live interactive event will take place, linking Aquarius aquanauts with students at various schools in Florida’s Broward County. The event will be facilitated by BECON, the Broward County Education and Communications Network.