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[editor's note, by Jason] Jon Warrenchuk is currently participating in NOAA's 2004 Gulf of Alaska Seamount Expedition.


August 6, 2004: Last night we launched the CTD. Marine biology is fairly light on acronyms, but this is one we throw around often. "C" stands for conductivity (a measure of salinity), "T" for temperature, and "D" for depth. Perturbations and combinations of those 3 factors (salinity, temperature, and depth) are primarily responsible for patterns of life in the ocean. This particular CTD also measures dissolved oxygen, another important limiting factor for marine life.

The CTD device is tethered to the Atlantis with fiber optic cable, and displays real-time data to the computer lab as it's lowered to the ocean floor. What's surprising is that dissolved oxygen decreases significantly after 200 meters depth and the water actually becomes quite "hypoxic" (low in oxygen). But after 1300 meters depth, dissolved oxygen increases. On seamounts that transcend this depth range, zonation of organisms is as evident as it is on a tidal seashore. It's cold on the bottom too, a consistent 1.6 to 2 degrees Celsius.

The best part about launching the CTD at night is that the boat is stationary and all the deck lights are on. When this happens, you never know what might ascend from the depths. Schooling forage fish, attracted to the lights, flash about in silvery streaks. A squid, about 3 feet long, quietly ascends, hovers, then disappears out of sight. I waited patiently for a salmon or two to make an appearance, but no luck.


[editor's note, by Jason] Jon Warrenchuk is currently participating in NOAA's 2004 Gulf of Alaska Seamount Expedition.


August 5, 2004: While there's always duping, clipping, editing, and highlighting those "oh cool!" moments of underwater video to be done, the flurries of activity really begin when the Alvin breaks the surface after a dive.

Tom Shirley's research is focused on documenting species that rely on deep-sea corals for habitat. It's relatively straightforward to video larger "macrofauna" such as crabs using corals as feeding platforms (and we see a lot of this). But it's more difficult to assess the habitat of those smaller critters that play an important part of the benthic ecosystem. Fortunately, Alvin is equipped with vacuum "slurpers" and these are used to "slurp" around the corals and collect any critters on the branches. This technique reveals a myriad assemblage of creatures not apparent on video. When the sub is winched back on board, we empty the slurp tubes and find many strange and wonderful creatures. We catalogued and preserved brittlestars, polychaete worms, shrimp, amphipods, and anemones for future identification.

After our samples were processed, a pod of about 20 Pacific white-sided dolphins zipped around the boat during sunset. It was very oceanic.


[editor's note, by Jason] Jon Warrenchuk is currently participating in NOAA's 2004 Gulf of Alaska Seamount Expedition.


August 4, 2004: Last night we left Denson Seamount and moved on to Dickins Seamount. Dickins is a shallower seamount, so I'm hoping to see more marine life. The waters above seamounts are supposed to be more productive than surrounding waters, concentrating plankton and zooplankton and the life that depends on them. I pictured swarms of seabirds in the waters above the seamounts, but there was not much evidence of this at Denson. I only saw a few storm petrels skimming the surface waters. Possibly Denson seamount is too deep for upwelling to occur.

Aha, there are a few more birds at Dickins, and diversity is greater too. I see about a dozen black-footed albatross, a few sooty terns, and more storm petrels. It's still not the circling swarm I pictured in my minds-eye, but it could be a significant observation. There's also a "boat effect" I need to address; albatross are curious and might come from miles around to check out a boat (there's not much on the horizon in the middle of the sea). I guess my feature article in "Audubon" will have to wait.


[editor's note, by Jason] Jon Warrenchuk is currently participating in NOAA's 2004 Gulf of Alaska Seamount Expedition.


AUGUST 3, 2004: Forget all this science. The real reason we're here is to squish Styrofoam cups! It's so cool! You take a standard Styrofoam coffee cup, decorate it with artistic license (mine had a "Jaws" theme), and stick it in a mesh bag tied to the sub. As the sub descends the air spaces in the Styrofoam get compressed and you're left with a much SMALLER Styrofoam cup! It makes a great souvenir.

Today Catalina Martinez, the expedition coordinator, gets to take a trip in Alvin. It's an exciting day for her. She has organized these expeditions for NOAA's Office of Exploration for 4 years, and today will be her first ever dive. They'll descend 2700 meters to the base of Denson Seamount. The launch is only slightly delayed, and off they go.

While on the bottom, they answered live questions from students in a middle school in Rhode Island, only 2700 meters up and a continent east away. This is the result of a satellite phone call, arranged by their teacher Carey Delauder, who joined the expedition as an "educator-at-sea". Her students are from an Urban Collaborative Accelerated Program and it's a neat way for kids to learn about the deep sea.

After she climbs out of the sub at the end of the dive, Catalina is greeted with water balloons and buckets of water. The veterans tell us this is tradition after your first dive. Sploosh! Welcome back!


[editor's note, by Jason] Jon Warrenchuk is currently participating in NOAA's 2004 Gulf of Alaska Seamount Expedition.


Monday, August 2: We've finally arrived at our first dive site. The early morning is spent "pinging" the bottom with multi-beam radar. This will generate the first detailed topography of the bottom structure and will be used to select the dive site. The peak of Benson seamount reaches to within 1100 m of the surface.

This morning, a small pod of Pacific white-sided dolphins frolicked in the wake beside the boat. They're the first marine mammals I've seen other than some whale spouts off in the distance. We're "standing down" for awhile to let the winds die down a bit before they launch the sub. The aquanauts for the first voyage will be Tom Shirley and Randy Keller.

Late morning and we're ready to launch! It's quite an operation. Alvin trundles out on a train track from the hanger and is loaded up with ballast weights. Divers don wetsuits. A zodiac is launched. Tom and Randy walk the gangplank and disappear into the sub. A giant A-frame crane lifts the sub and lowers it into the water. The divers ride the sub a ways and check that everything is ok, and then the sub slowly sinks out of sight.

Six hours (and a few ping-pong games) later and Alvin breaks the surface. The retrieval operation proceeds much like the reverse of the launch operation. The sub is lifted on deck and scientists gather around like over-eager children at Christmas. And it is Christmas! Presents from the deep! Slimy, spiky critters and rocks!

The collecting boxes and suction tubes are loaded with goodies. I retrieve some kind of king crab species from the collecting box for Tom. With identification keys, I confirm that it's a female Paralomis verrilli. It's not well-known enough to have a common name. It does resemble the more familiar red king crab, but is "spikier".

We even find some unexpected critters in the corners of the collecting box and on pieces of coral: a delicate deep-sea spider on a small piece of bamboo coral, undescribed copepod species, and a small crab we couldn't identify. All are preserved in digital and alcohol media and added to the body of science on deep-sea biology.

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