We woke early, just as the first rays of neon aquamarine light spilled through the bow port window. After gobbling down oatmeal and hot cocoa we donned our wetsuits (still wet and slimy from the day before – yuck). We helped each other slip into the straps of our double tanks and headed out to check on the instruments we had placed on the reef the evening before.

During the night, we had formed an impromptu science meeting to discuss the exciting data we saw streaming across our computer screens coming directly and in real time from our suite of chemical sensors. We now wanted to test a slightly new hypothesis about the diel (24-hour) cycle of sponge and seagrass physiology and this would require a bit of “remodeling” and “plumbing” of our hardware scattered around various sites. What does that mean for our friends at Conch Reef? Well I guess, it’s a little like the signs I saw at Miami International Airport, when I flew in to be a part of this mission – our experiments for the time being are “Under Construction.” Fortunately for our fine fish friends, we are only visiting on the reef for 10 days before they get the keys to the Aquarius “condo” and the wetporch back.

Aquanaut Luis Camilli

Hopefully our work out at Aquarius Reef Base will help us to understand how to distinguish local acidification processes, like that from sponge respiration, from the global scale changes now occurring around the world. Only in this decade have scientists fully realized the threat of global acidification to calcifying organisms such as corals. Marine scientists around the world are now attempting to provide the information that we need to both understand and manage this important problem. Aquarius Reef Base has provided us a useful observatory from which to launch some of these efforts.

Aquanaut Chris Martens

Among many tasks on the daily checklist is to change out the buckets of soda lime for our carbon dioxide scrubbers in the Habitat.  Why do we have to “scrub” the CO2 out of the air?  Well, essentially as our bodies use the available oxygen in the air to convert sugars into energy for cellular processes – everything from firing neurons, to heart contractions, fighting infections, or digesting dinner – the result is the production of carbon dioxide as a byproduct of these physio-chemical processes referred to as cellular respiration.  Given that at any given time there can be up to six people living in a cylinder the size of a bus may give you an idea of how much respiration is going on inside of Aquarius – incidentally related to similar chemical processes we are studying on the reef outside. 

In fact, earlier in the day we placed a couple of cylindrical enclosures (about the volume of the inside of a washing machine) around various sponges and used stable nitrogen isotope tracers to see how long it would take the sponges to respire.  The enclosures, while circulating the existing water with submerged pumps, ensure that no “fresh air” reaches the sponges during our experiments.  For awhile, it looked as if the sponges were in an intensive care unit, hooked to tubes leading to a mass spectrometer and nitrate/pH sensors complete with hanging “I.V. bags”.  What we are seeing is that it doesn’t take long, sometimes a matter of a few minutes, for these sponges to respire and significantly change the pH and level of dissolved gases (i.e. oxygen, nitrogen, carbon dioxide) in their immediate environment.

Living underwater at Aquarius and conducting these experiments makes me realize just how critical (and difficult) it is to maintain the necessary balance to sustain life in an environment that is different from your own. In some ways the Aquarius Habitat can be thought of a microcosm of life on earth.  We as humans – like other animals, require a unique mixture of earth, wind, fire and water. This may seem a little obvious until you consider the broader implications of rapid environmental change we are noticing on our planet.  This little pressurized bubble called Aquarius literally means the world to me – it is a habitat that I can’t live without.

Aquanaut   Luis Camilli

To move the equipment to our new site we took off our fins, released air from our BCDs (Buoyancy Compensation Devices) and walked each heavy piece across the seafloor stepping only on sandy spots. We usually use BCDs to stay neutrally buoyant in the water column like a hot air balloon- this makes it possible to float around above the reef surface without touching corals and other living organisms. When you get “heavy” by expelling air you settle to the bottom but only experience a fraction of normal gravity and so it’s like walking on the moon. That’s why astronauts often train at Aquarius. You’ll see our new site on the web soon- we’ll call it Moonbase”!

Aquanaut Chris Martens

James Talacek is the lead habitat technician in Aquarius this mission.  He says that the primary job of a Habitat Technician (HabTech) is operation and maintenance of Aquarius.   For he and Nathan Bender (the other habtech this mission) the day starts at 6:00am when they perform a daily checklist that covers all aspects of habitat operations and ensures that all systems are ready for another day of diving.

They next act as divemasters for the scientist aquanauts, getting them out diving on the reef to work on their various science projects and overseeing their dive plans and safety.

After that James and Nate spend the day monitoring life support systems and communicating and coordinating with the shorebase crew on conditions in the habitat, daily needs, and any issues that arise. When the surface crew comes out to make deliveries, they work with them to receive supplies. They each also spend quite a bit of time in the water using rebreathers or on hookah to perform habitat husbandry (scraping, cleaning, and all general maintenance activities) and often have construction projects to work on.

The habtechs end the night with a final systems check and then get some much needed rest to do it all again the next day.

James says his favorite part of living in Aquarius is getting to see all the cool underwater life around the habitat.  Living underwater provides the opportunity to view marine life 24/7 – much better than if you were just doing a short dive from the surface.

This is Nate’s first mission as a habitat technician and here is what he has to say about it:

“It’s wonderful here.  The days are long. but they fly by – unfortunately.  Right now, we’re catching up on some improvements, so if we’re not putting in new swinging stools or feaux walls, we’re “busting rust” outside.  This experience is more than I thought it would be.  The hardest thing about being here is trying to stay focused when I’m out on hookah.  I have to remember that this is my job, and to quit staring at the goliath groupers.  Watching those guys “boom” when they eat and getting run over by a nurse shark have been awesome experiences.  On the rebreathers, it’s a different experience, I’m sure, because the marine-life aren’t as suspicious, and you don’t have bubbles masking your hysterical laughter when you are taking all of this in.”

Thanks James and Nate, keep up the great work and have a good time down there!

I love night dives at Aquarius!

Tonight we first worked at our “boring sponge” site dominated by Cliona varians. This sponge species actually bores into the coral rock, eventually reducing it to sand and rubble.

Twilight was fading as we swam out of the Aquarius wet porch a little after 7:00 pm. The water was warm and all seemed calm out on the reef. After photo- and video-documenting the site using powerful LED lighting we circled back across the big sand patch on which Aquarius rests- this area is named the Carpenter Basin after the famous astronaut, Scott Carpenter, who was at Aquarius after going into space. The sand patch looked like a snow-covered field between rock fences in New England. The outside lights of Aquarius plus interior lights glowing out of the viewports were a much wilder scene! Herbivorous fish were swirling through the light feeding on plankton attracted by the light. Off the “bow” or the bunkroom end of Aquarius which points north towards Tavernier, the scene was even better! A group of goliath groupers, including several giants weighing over 300 pounds, were hovering and circling just outside the viewport. Frequently they were snapping up unwary fish blinded by the light, making a loud booming sound as they quickly lunged and gulped down sardines and other morsels. Occasionally scales from an unlucky victim cascaded down through the water column, however, groupers feed by quickly opening their mouths and engulfing their prey leaving little evidence and no mess. What an interesting alliance between humans and fish! Several of these goliaths have been around Aquarius for years and we’ve all gotten to know each other. NOAAH, who used to be the little 50 pound baby and now a big boy probably over 150 pounds, swims up when we’re gathering under Aquarius to see what we’re doing. Yesterday I rubbed his tummy! Earl, larger and more cautious, keeps a bit of a distance for now but will relax as the mission goes on. Sometimes the goliaths hang out in the wet porch above the grating we step onto as we suit up to dive- look for photos on the website. After the mission we’ll post some night video of the goliaths “fishing”!

We ended the dive at about 8:20 pm. I hunted for basketstars as we circled above the reef around Aquarius on the way back to the wet porch. What a privilege to experience the ocean at all hours of the day and night. Hopefully our work will contribute to understanding what’s causing reefs around the world to degrade- there’s a lot to be lost if we don’t take care of this special resource.

Now it’s time for that little bunk of mine- I’ll sleep tight knowing that Earl is just outside my window, I mean viewport, watching over us!

Aquanaut Dr. Chris Martens 

(Note that the Aquarius sits in a no-fishing, research only area within the Florida Keys National Marine Sanctuary and is regularly patrolled in between missions – one reason the fish life is so wonderful around the habitat – and we want to keep it that way)

The impacts of global warming on the ocean and its ecosystems are a matter of worldwide alarm and much speculation. Corals are particularly sensitive to ocean temperature and chemistry. While we are making progress in understanding the impacts of rising temperatures on coral reefs, far less is known about the effects of the sea’s changing chemistry, in particular rising ocean acidity.  Recent research has confirmed that as concentrations of carbon dioxide have increased in the atmosphere so too have levels in the ocean and this has led to a slight lowering of the ocean’s pH.  It is a phenomenon now widely known as ocean acidification.  Along with affecting widespread biological processes, ocean acidification is expected to specifically impact organisms, which create shells or skeletons of calcium carbonate, such as corals.  Evidence, mainly from laboratory experiments, suggests that the calcification rates of many such organisms will decrease as the ocean’s pH declines.  Scientists estimate, based on these results, that calcification rates in the ocean could decrease by 60% within the 21st Century.  This could have a huge impact on corals and the structures and ecosystems they create.  However, controlled experiments in the laboratory simplify the impacts of ocean acidification and probably neglect a wide range of presently unknown environmental, biological, and ecological influences.

The Aquarius undersea laboratory is especially well suited to be at the forefront of in situ studies of ocean acidification impacts on coral reefs and the upcoming mission is an excellent start.  Drs. Chris Martens and Niels Lindquist will lead a team of researchers and technology experts to examine how pH and water chemistry change over hourly, daily, and weekly time frames on the reef, especially right near the seafloor where most of the organisms reside.  They will try to distinguish between local and global pH changes and work with their partners to test state-of-the-art technology for monitoring water chemistry on very fine scales in situ.  We look forward to following their progress and seeing what discoveries they make.

Hope you will all follow along.  Training starts Monday as the aquanaut candidates work with our expert staff to prepare for their time living among the fish and studying a very important topic in today’s changing climate!

Dr. Ellen Prager

Chief Scientist, Aquarius Reef Base