The mission began the researchers’ two-year investigation on how grazers, specifically parrotfish and surgeonfish, affect seaweeds and corals in the Florida Keys National Marine Sanctuary. Using Aquarius, a 47-foot cylindrical lab, gave the researchers an ideal platform from which to set up their experiments and make observations.
Aquarius is a one-of-a-kind underwater ocean laboratory deployed three-and-a-half miles offshore, at a depth of 60 feet, next to spectacular coral reefs. Scientists live in Aquarius during 10-day missions using saturation diving to study the ocean.
Aquarius, owned by NOAA, is operated by the National Undersea Research Center (NURC) at the University of North Carolina at Wilmington.
Here are excerpts from the journals Hay and his team members kept during the mission.
Day One – Nov. 10
As you approach the Aquarius at night, it is a lot like approaching a strange spaceship you find in your corn field. Faint lights glow off in the distance, and as you get closer there are the strange, low-frequency murmurs and throbbing sounds of compressors and pumps. There is a Darth Vader-like breathing sound made as air enters and exits the wet-porch on the back of the Aquarius as waves pass overhead. You see shafts of light before you can tell where they come from. Clouds of fish swirl around. Then, finally, you see Aquarius with lights glowing from view ports and from mounts above or around the structure to enable Aquanauts to see activities outside.
It’s a wonderful experience. To put it in the “southern” context, think of a single-wide trailer beside an isolated road in the pines. The trailer is absolutely packed with strange electronics, safety equipment and pressurized gas tubes, bottles, etc. But instead of hounds on the front porch, we have 50 to 100 barracuda and clouds of smaller fish, and instead of the back seat from a 1962 Oldsmobile station wagon on the porch, we have five double sets of 100 CF scuba bottles with double regulators, multiple isolation valves, two long reels of line for navigating away from our normal excursion lines, and sealed VHF radios in case we surface and need to call for help. All of these things are critical when needed, but all a pain in the ass during our normal day when we would like to move faster, have less and use the large pockets for science gear rather than safety gear.
– Mark Hay
For everyone who has ever wondered what fish in an aquarium feel like, well, I think I know. We are now living about 47 feet under the ocean in a big metal tube. I thought it would be uncomfortable and cramped. But it’s really not. We have several portholes where we can watch the fish outside. Or are they really watching us?
courtesy of Mark Hay
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A diver checks a cage that researchers installed as part of an investigation on how grazers, specifically parrotfish and surgeonfish, affect seaweeds and corals in the Florida Keys National Marine Sanctuary.
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It’s like a reverse aquarium, a "humanarium." Sometimes I get the feeling that the fish just swim by to take a look at us to see what the humans are doing.
…. While we were working on our cages and hammering nails into bare ocean bottom, little critters would light up like light bulbs and glow. They were fluorescing. Every time I hit a nail with my hammer, I was treated to a little starry night light show right in front of me.
– Deron Burkepile, Georgia Tech Ph.D. candidate
Day Two – Nov. 11
Apparently, it’s a rough day top-side. Our surface supply divers were unable to come out today. For us, things were fine, but there was a screaming current from the north, northeast. This made it hard going to get to our study site and to the northeast fill station, but the “ride” home was fast and easy once the day and night were over.
Today we did a six-hour dive, then a mandatory four hours off, then a three-hour dive, and then we had to stay in for 12 hours before we could go out again. But after nine hours in the water, we were pretty wrinkly and ready for some food and rest. The last three-hour dive included about two-and-a-half hours of diving after dark, and we saw a lot of sleeping, or at least addled, fish up close. We got some good photos of surgeonfish, a scrawled filefish, and lots of basket stars spreading into the currents from their perches on gorgonians or sponges.
On our three-hour dive in the evening, we had light from 5 to 6 p.m., but by 6 p.m. at this depth and time of year, it is truly dark. To free our hands for working – driving nails to fasten cages to the reef – we strapped small flashlights to our mask straps and were able to work productively for the extra two hours in darkness. Because we are running on 25-hour work cycles (six hours out, a mandatory four in, three out, then another mandatory 12 hours in), we end up going out one hour later each day. Thus, tomorrow our second dive will start at 6 p.m., and the whole thing will be largely in the dark. The mask-mounted lights are going to be heavily used.
– Mark Hay
Day Three – Nov. 12
We had to cut the second dive to only two hours so we could get the required 12-hour storage and be back out earlier tomorrow and use the daytime better. The current was strong. It kept pushing me into every cage as I worked on the up-current side.
courtesy of Mark Hay
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Researchers had to eat dehydrated and pre-packaged food while living aboard the Aquarius underwater laboratory based in the Florida Keys.
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We saw several nice eels, but the best sight was the re-approach to the Aquarius. As we got close enough to hear it, I cut my light, and since I was in front, I was looking into the dark, but the lights of the divers behind me provided some faint light. Against the Aquarius’ light and outline, we could see thousands of fish completely filling the water column. There were what looked to be more than 100 reasonably large barracuda, several large snapper and then dense clouds of smaller fish. It was a striking sight to see how may fish were attracted to the lights, sounds and structure of the Aquarius.
One wonders what these and other Caribbean waters were like before fishing removed so many of the larger consumers. During my 26 years of diving, there has been a dramatic decline in the numbers, types and sizes of fish on reefs, but maybe I started well after the decline. Maybe this would have been common 200 years ago. I’m delighted to get to see it now. I wish my sons, Hunter and Kyle, could have been on the swim in to the Aquarius tonight. I fear that there are few chances to see these sights now, and that these chances will be even fewer in the future.
– Mark Hay
From the view port near my bunk, fish dart frantically to and fro while jellyfish ride the current past. I'm not sure if I will ever get used to looking outside and seeing these sights. After a quick breakfast, we've got a 10-minute commute to our research site. Typically there is a strong current going against us, making my arms strain as I move along the excursion line. It’s as frustrating as a traffic jam.
The day passed rapidly; it was filled with construction details. Remarkably, it's easy to get lost in the work – hammer, hammer, cable tie and snip. Then, a small, brash damsel fish will jet over to nip your leg for loitering in its tailored algae garden, immersing you right back to the reef. I think it is crazy how quickly we've habituated. Nine hours on the reef becomes normal.
Still my favorite parts of our dives occur at night. Last night while returning to Aquarius, our dive lights set off some hand-sized fish into a hypnotic frenzy. Darting and swirling, the little dervishes ricocheted three times off my head as we swam. It was surreal. Only through Aquarius could I get whacked in the head by a living fish more than once.
– Todd Barsby, Georgia Tech postdoctoral associate
Day Four – Nov. 13
We are concerned about moray eels being inadvertently captured in our cages and thus getting our fish. We canvassed the cages one night and saw none in the cages. But we noted one in Cage 17 today, though it was not especially large, and we can probably get him to leave with minimal hassle.
courtesy of Mark Hay
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Space was limited for researchers inside the Aquarius underwater laboratory based in the Florida Keys.
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Cage 24 has a lot of structure and holes in it. We have seen a big eel in there. This morning there was a large hole blasted directly through the chicken wire where something came out through the top of the cage and a second hole in the side where something came back in. In both cases, it looked like a rocket had gone through the cage material. These are impressive animals.
– Mark Hay
Day Five – Nov. 14
The current was modest this morning, but picked up in the afternoon. We finished patching imperfections in the cage bottoms and will soon be able to start quantifying the benthic community and then adding fish.
During the afternoon dive, the current picked up more, and at dusk, high densities of jellyfishes started washing through. As these came over the reef, the yellowtail snapper and bar jacks were rising up in the water column and attacking the small fish that were sheltering in the jellyfish tentacles.
There were often frenzied predators around each jelly, but as this started and the snapper and jack focused on their prey, larger jack and barracuda started going after the snapper and smaller jacks. In most cases the frenzied fish dispersed as the larger predators approached, but there appeared to be a few successful strikes by the larger predators. The low light and speed of attack often make this difficult to judge.
– Mark Hay
Here’s what we eat: chips, chocolate, cookies and three kinds of cheese – shredded, cubed, and stringed. These are the four Cs of Aquarius. To balance our diets, we supplement with anything we can microwave or rehydrate (yum). This makes for some great snacking and some not-so-great meal times, as you could well imagine. My take-home tip of the day: Dehydrated scrambled eggs and bacon is best used directly as fish food. Really, just skip the more common, intestinal track all together. Trust me.
– Todd Barsby
Day Six – Nov. 15
We only have 20 more hours of diving in total, and then we will be locked in for decompression, so it is crunch time. Everyone has been good to keep at it consistently without deciding to kill anyone.
courtesy of Mark Hay
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This reef crab was among the creatures that Aquarius mission researchers observed.
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We are beginning to get the predictable suite of undesirables at the cages – sharks, big jacks, big grouper and snapper, and holes in the cages from big eels. Once fish swim into the open cage and start getting freaked-out that they can't find their way out, their activity attracts the predators.
I spent several minutes this morning convincing a 5-foot nurse shark that it needed to go elsewhere and leave the cages – and the fish in them – alone. It amazes me that fish will stay against the cage edge and get sucked through the mesh by these sharks. All the prey need to do is stay away from the edge, but they don’t. I guess destructive behavior is not just a human trait…
Our surface team graduate students, Brock and Zack, came for a lunchtime visit today to experience the Aquarius. They thought the place was interesting. We longed for their freedom to go to Sharkey's and have chicken wings and a beer. So Brock made etouffee and sent it down to us for dinner. The freeze-dried camping foods we’ve been having are good, but it was great to get this.
We have all started freezing on our dives. Everyone has on multiple layers of wet suits, and we are still getting cold. I can't tell for sure if we are getting tired, if the wet suits are depressing and becoming inefficient (I'm sure this is happening, but the magnitude of the effect is uncertain), or if the water really got colder today. Upwelled colder water does occur along here, but I can't really say it started today.
– Mark Hay
Day Seven – Nov. 16
On the way to the site this morning, I was pulling along the excursion line – not paying adequate attention – and ran my forehead into a jellyfish. I was lucky that it was a moonjelly and not one of the cauliflower jellies. It stung at the time, but went away before long.
We have seen some massive cauliflower jellies. One that came over us today had tentacles extending 10 to 12 feet down through the water column and could have easily hit one of us without us seeing the body first. I had not seen this species before, and on this expedition have seen many.
– Mark Hay
Day Eight – Nov. 17
Our wet suits are mashed, shrunken, inefficient and fighting back. We are freezing, despite multiple wet suits. They are rubbing the skin off our bodies in places and causing rashes in others... We need to dry out.
– Mark Hay
Day Nine – Nov. 18
Last night the waves must have really picked up. The Aquarius shook at times with the surge, and the wet porch hissed and moaned loudly as water was forced in and out due to wave surge.
courtesy of Mark Hay
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The Aquarius researchers had to undergo decompression at the end of their mission. They initially got 70 minutes of oxygen treatment while lying in bed. It helps wash out the nitrogen in their bodies.
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When we got up this morning, it was uncertain that we would be able to dive. Safety mandates that the fast boat from shore has to be able to get here and back should we have a surfacing emergency. We also have to be able to see our excursion lines to get back to the habitat. The visibility looked bad, the surface folks were unsure of their ability to respond, and there was some question about the advisability of us going out.
After considerable discussion, we were allowed to go after giving a promise to abandon the effort if things were too bad. Once out, the visibility was poor, but it was not hard to maneuver. There was surge, but it was not bad. The hard directional currents of earlier in the week were tougher on us.
We did use our safety reels at each cage site – hooking a line to the excursion line, swimming the reel to the cages and affixing it, then working them and reeling ourselves back to the line.
We started decompression at 4 p.m. We initially got 70 minutes of oxygen treatment while lying in bed. This gives us an initial jump on washing out nitrogen, but has some risk of oxygen toxicity at this pressure. All went well. We then watched two movies and read…. It was like watching paint dry.
The pressure was slowly vented to bring us to surface pressure. At 11:40 p.m., we were at 16 feet. The assent goes faster earlier and slower later, so those last 16 feet took another eight hours.
– Mark Hay
Day Ten – Nov. 19
We emerged to bright sunshine, a warm day and fresh cinnamon bread. It was nice to be back on top, but we’ll miss the time in and under the water. Later, we had lunch – good Mexican food and a beer. The diving physician had to go with us to be sure no one showed signs of decompression, but he was willing to do this so we were “paroled” from the NURC base.
– Mark Hay
For more information, contact Mark Hay at 404-894-8429 or mark.hay@biology.gatech.edu. For more information on the mission, see www.uncw.edu/aquarius/.
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Last updated: March 31, 2004
