We had an incredibly productive science day today. Jim and I repositioned some of the flow probes over different barrel sponges to measure the rate that they can pump water. Tomorrow, Jim will collect water samples from the same sponges to be analyzed for different components to see how much material they are removing from the water with their efficient filtering mechanisms and how much they are releasing in terms of certain nutrients.

n addition, the four of us spent most of today working on our control volume sampling apparatus. We successfully collected six sets of samples – totaling about 60 samples in all – to be analyzed for chlorophyll and nutrient concentrations. As mentioned earlier, this will allow us to see how much ‘stuff’ the reef is removing from the water column. This is a relatively labor intensive process and requires significant help from and coordination with our amazing surface support team (without whom, this project would be impossible!). Our two aquanaut dive teams spent over well over twelve hours total in the water today – mostly around 70’ deep. This would be impossible to do if diving from the surface (without significant decompression each day). Everyday, we realize more and more how valuable the Aquarius platform is for accomplishing science out on the reef. Studies like ours simply could not be done here otherwise.

Long amounts of time out in the water give us the chance to observe and reflect on phenomena around us. One observation that we have all made is the amount of scour and sediment movement that occurred from the waves generated about a week ago by hurricane Dennis. In the shallow waters (around 50’ deep), most of the former sand patches have been eroded to a hard, old coral reef pavement. Some of this pavement probably has not been exposed in many years. As you get deeper in amongst the spur and groove of the lower reef, we still see significant scour (at around 65’) in the deeper sand channels. However, starting around 70’ deep, sand waves appear in the sand channels that, though relatively small, are still about 10-15 cm high. In these areas, there are alternating bands of exposed old reef and buried new reef. Some corals and soft corals that were healthy only a week ago are now buried under the sand, and new, barren substrate is exposed opening space for the colonization of other organisms. This is a very natural process that transports sediment from the shallow to the deep reef, but large storms tend to accelerate what is generally observed to be a reasonably slow process. It is fascinating to observe these dramatic effects, and our curious minds have already been mulling potential projects to explore the details of such events.

At the end of the day, we are exhausted, yet happy knowing that we accomplished so much. We are beginning to realize that our time under the sea is drawing to a close (only one full working day left!!!), but, for now, we must focus on the science that we need to accomplish and enjoying the watery world around us.

The surface support crew did a spectacular job once again, and always seemed to be diving down the lines to grab our samples just as we were finishing the experiment. As the day wore on, we all started to feel the cold a little bit, hanging out at 70 ft. Jim had the smart idea to hover around 60 ft where the water was noticeably warmer, so we each took turns running samples, taking pictures, or watching the action from above. I got some great shots of this big old lobster that was sitting behind us under some rocks. He seemed fat, happy, and content watching these funny looking humans wandering around the reef.

Kristen and I stayed out until 5:30 pm while Greg and Jim maintained the station for one last set of samples to be collected. Around 7:30 pm our last set of samples were done and the surface crew headed in for the night.

Hopefully tonight I’ll make it out for my first “hooka” run to do night photography. I’m pretty excited about it and crossing my fingers the nurse sharks will still be there. With so much time in the water, I think I’m starting to grow my own fins. Not that I’ll need them, the fish don’t seem to care one way or the other if I’m there.

Our time here so far has been very productive! We have been spending most of our time during the first days getting the equipment ready for the control volume experiments.

One of the coolest things about spending so much time in the water is that you see things that you wouldn’t normally have time to notice: fish making mistakes and bumping into things, big fish eating littler fish, some really aggressive little fish who push the big fish (and us!) around. Last night we were treated to several Caribbean reef squid displaying outside the dining port hole.

Well, the time has come for me to stage out on hookah and get some work done outside. It gets pretty busy down here as we always try to maximize our time in the water taking care of business, looking out for our science team and claiming back our habitat from the constant growth of marine life.

I spent around four hours out on hookah today cleaning and working on the outside of the Habitat. It’s a constant battle when you put something on the sea floor and the ocean begins to claim it for its own. Valves and piping must be cleaned regularly and working from saturation allows us to get long dives in and give the habitat the attention she needs and deserves. Today while working, I dropped a tool and when I looked down, I saw fish of all sizes a dart around it. As I dropped down to retrieve it I saw what all the excitement was about……a large ball of bait fish or “silver sides” was swarming underneath the habitat. Every one was trying to get in on the action, several large Nurse Sharks and a big Atlantic Stingray were in the thick of it all, with about a dozen Black Grouper racing through the fray gulping up mouthfuls of fish. All of the action had the smaller Snapper and Yellowtail all worked up as well zipping about in every direction. When I first saw the bait ball it was about 12 to 15 feet across, but after about 2 hours it was reduced to a small scattering of little fish, the Nurse Sharks lounging on bottom, fat and happy after their very large meal.

The ocean is full of amazing sights, it’s never a dull moment down here.

As for the science (ah, yes the less interesting but *real* reason we are here!), we had a very productive day. Jim and I were able to deploy current meters in some barrel sponges today. These will be used to see how fast these primitive animals pump water through their bodies. Sponges are incredibly efficient at filtering water, so we will also be sampling the water to see how much food and oxygen the sponges can extract. Kristen and Matt, with help from our amazing surface support team, spent much of their dive time setting up the pumps we are using for the ‘control volume’ experiment. It appears that everything is in working order, but we have to fine tune some of the pumping rates to get the experiment just right. If things go well, we should be able to start collecting data on this part of the project tomorrow. We are still amazed that each dive team could spend six or more hours out on dives. Of course, this still isn’t enough time!!! Yes, we scientists are never satisfied!

Ross and I are spending time in the water cleaning valves and related equipment. We also tightened down a hold down chain or two that was loosened by the storm. Every now and then we get distracted by the reef community around us. I saw a large nurse shark in a concentrated search pattern on the bottom. Then I spotted it’s prey. There was a dead snapper resting nearby that the shark quickly found and sucked into her mouth with the efficiency of a vacuum cleaner. Then, while scrubbing a valve handle, a curious green moray eel came along and rested his head on my arm for a moment. I said hello and he went about his business.

This group of Aquanauts are spending lots of time on the reef. Keeping busy makes the time fly by. Saturday already!

As Habitat Techs, my partner Mark “Otter” Hulsbeck and I, are responsible for keeping up with the day to day activities of maintaining and running Aquarius, as well as looking out for our scientists and helping to facilitate their science.

At any given time, one of us is inside freeing up the other to go out on “Hookah”, a habitat supplied umbilical that gives us a virtually unlimited air supply, and allows us to clean and check critical systems on the outside of the habitat. Each morning after getting the scientists in the water, we perform a daily check list to make sure all aspects of the Habitat are in good working order.

This is day one of what we hope to be a very productive mission. This project has a diverse group of scientists from all over, including Stanford, the University of North Carolina, UC Berkeley, and the Hebrew University in Israel.

Today was my first time inside Aquarius. If you’re wondering what it’s like, it’s sort of like being in the school bus you always wanted to have when you were in 3rd grade — your friends, a can of Pringles potato chips, and an ocean swimming by in the lights.