Tech's "aquanauts" — including Georgia Tech professor Mark Hay, postdoctoral associate Todd Barsby, PhD student Deron Burkepile and research specialist and technician Alex Chequer, along with National Undersea Research Center scientists Mark Hulsbeck and Thor Dunmire — were aboard the National Oceanic and Atmospheric Administration-owned Aquarius ocean laboratory in the Florida Keys National Marine Sanctuary. Tech graduate students Zach Hallinan, Brock Woodson and Anne Prusak provided support for the mission from the surface, diving to the site on a daily basis.

Aquarius, a 47-foot cylindrical lab, is deployed three and a half miles offshore, at a depth of 60 feet, next to spectacular coral reefs. Mission scientists use saturation diving to study and explore the coastal ocean.

Hay, who led the Aquarius mission, is an experimental ecologist and holds the Linda and Harry Teasely Chair in Environmental Biology in Tech's College of Sciences.

This mission on Aquarius was the beginning of a long-term study by Hay and his team. The team will monitor changes in algal and coral cover and composition within 32 6-foot-by-6-foot-by-3-foot cages. They should start seeing differences in seaweed growth and cover and how it affects the corals, Hay says. The team photographed the corals in each cage at the end of the November mission and will rephotograph the corals after six months and a year to see how the corals have changed.

The team spent nine hours per day diving, the physiological limit at that depth while saturated. "Saturation diving" is a technique that permits divers to remain at high pressures for weeks or months without having to often undergo decompression and waste the diver's time resurfacing each day.

Working at the dive site before dawn and as day turned to dusk provided interesting opportunities to observe different marine life.

"The coolest thing to me was to see the changes in fishes at dawn and dusk. We'd start before the sun came up and we'd see the reef wake up as the nocturnal fishes went away and the daytime fishes starting to move around," Burkepile says. "It was equally neat to go from light through dusk to darkness and to see all of the predatory fish come out at dusk. You'd see huge schools of fish — 50 to 60 barracuda all together — swimming around right at dusk."

The long days of diving and constructing the cages underwater were physically draining, and the bedroom accommodations were less than spacious — about 7-by-8 feet with two sets of bunks stacked three high with a little less than two feet of space between bunks — but everyone slept well, given the daily schedule.

"We slept very soundly at the end of the day because we spent twice as much time in the water as we could have diving from the surface," Burkepile says.

©2004 Georgia Tech Alumni Association