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MISSION DISPATCH 5 • 4/19/01 - 4/20/01 Today's Weather - images courtesy of NOAA & RSMAS 4/19/01:1700 - Pre-Dive Preparations Under Way With just two hours to go before launch time, there are still some preparations to be made. The PANTHER submersible rescue ROV is launched and put through its paces. If it had to be called into service to recover a crippled sub, the ROV must be up to the task. 
It is unlikely that the PANTHER would ever need to be used. Redundant safety features a part
of the JSL subs. They allow any of the four persons on board to bring a sub to
the surface, even if it has lost power. The human safety issue is never a debate,
if the JSL or the ship encounters a problem that qualifies as a safety risk, dive operations
are suspended.
We are a go for the first of three submersible dives slated to occur over the evening hours of 4/19 - 4/20. The conditions are favorable, with seas averaging 3-5 feet. 4/19/01 - JOHNSON SEA-LINK DIVE #4279 28°02.1203' N • 79°46.3106' W • Western Gulf Stream, off of Grant, Florida Personnel - Sphere • Sub Pilot: Phil Santos • Scientist Observer: Marsh Youngbluth Personnel - Aft Chamber • Tender: Ben Chiong • Diver: Christina Bendix Andersen Launch Time: 1951 • Time to Surface: 2146 • Dive Duration: 1 hour, 55 minutes 
The sub is launched at 1951, after a quick sub team briefing aboard the ship. The first
40 minutes of the dive is spent at less than 150 foot depth, which is where the scientists
believe the large appendicularian Bathochordaeus might be concentrated. So far, however,
Marsh has not seen the target animals. This news, taken along with the fact that the
MOCNESS tow earlier in the day came up empty, suggests that the scientists may not be looking in
the right place within the water column.
At 2033, Marsh has the pilot take the sub down to 250 feet. Bingo. The MOCNESS tow this afternoon had missed a population of the target appendicularians by 100 feet. Everyone should have a JSL submersible to do this kind of work. The next hour of the dive is spent in what the sub pilots refer to as a "target-rich environment" - appendicularian containing depths between 210 and 240 feet. High resolution videotape footage of appendicularians in their feeding houses is acquired, and the six detritus samplers mounted on the front of the sub are called into action to collect individual animals and houses for shipboard study. By 2141, all six collectors are full. The sub surfaces at 2146. The scientists on board refrain from rushing the vehicle until it has been safely secured on the aft deck. Then a flurry of activity begins. Initially, flashlights are used to verify the presence of the appendicularians in the samplers even before they are detached from the sub. It takes a while even for the experts to see a clear animal in a clear house in an acrylic chamber of clear seawater. But when the flashlight beam strikes it the right way, the telltale refraction of light off of the translucent body of the cryptic animal allows visual confirmation. 
Each scientist in the team has his or her own specific interests in the animals that come up in the collectors. Mission dispatches over the remaining days will elaborate some of these interests. Suffice it here to say that each of the scientists wants a piece of each animal or house collected. The fecal pellets are preserved and set aside for organic chemical analysis. Dead animals are examined for morphological characters, and portions of these are also set aside for later study. Some of the houses will be used in chemical analysis, while others will be scrutinized for their architectural and functional details. The animals that remain healthy and intact are mostly left alone, to see if they will inflate and take up residence in new houses under laboratory conditions. 4/20/01 - Two More JSL I Dives Two additional shallow water sub dives are successfully completed. The final dive of the night surfaces at 0630 on Friday morning, just as the sun begins to rise. Both of these dives return with full collectors and a cassette full of videotaped in situ observations. 4/19/01 - JOHNSON SEA-LINK I - DIVE #4280 28°10.6277' N • 79°45.9606' W • Western Gulf Stream, off of Grant, Florida Personnel - Sphere • Sub Pilot: Phil Santos • Scientist Observer: Per Flood Personnel - Aft Chamber • Tender: Ben Chiong • Diver: Jennifer Bossart Launch Time: 0013 • Time to Surface: 0205 • Dive Duration: 1 hour, 52 minutes 4/19/01 - JOHNSON SEA-LINK I - DIVE #4281 28°:11.4609' N • 79°:47.3110' W • Western Gulf Stream, off of Grant, Florida Personnel - Sphere • Sub Pilot: Phil Santos • Scientist Observer: Alexander Bochdansky Personnel - Aft Chamber • Tender: Ben Chiong • Diver: Jimmy Nelson Launch Time: 0444 • Time to Surface: 0624 • Dive Duration: 1 hour, 40 minutes 0800 - Scientists Tired But Happy It has been a very long night. Telling the shipboard personnel they are immediately going into night ops mode in the middle of the previous day's shift is like telling a runner in the middle of the Boston Marathon that this one's just a warm up and that the real race will start in two hours. 
But everyone seems happy with the success of the first science dives of the mission. The
target animals are here, and we have demonstrated that we can capture them. There were even
two animals that started inflating new houses in the lab, although they abandoned them before
completion. The consensus of the scientists is that the animals don't like the high frequency
vibrations of the ships constantly running engines. They are now considering how best to minimize disturbance to the animals.
Just about everyone has gone to quarters to get some much-needed sleep. The next evening's dives are set to begin at 1930 on Friday evening. The scientists may decide to try a couple of deeper MOCNESS tows in the afternoon, to see if they can bring up more of the target animals they now know are here. This expedition is made possible through a grant from the Biological Oceanography Program of the National Science Foundation with additional support from Harbor Branch Oceanographic Institution.  | |
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