 |
JULY
12-13:
|
The JSL is launched from the RV Edwin Link taking Drs. Tammy Frank and Edie Widder into the depths. Sub pilot is Phil Santos. Video by James Gordon
|
Science team member Uli Siebeck, from the University of Queensland in
Australia, takes a detritus sampling bucket from the JSL to the lab. Woods
Hole's Sonke Johnsen is following.
|
 |
|
Click below to learn a bit more about this advanced and versatile deep-sea research tool...
|
|
 |
|
|
 |
|
Accomplished videographer Brian Cousin is doing double duty on the Gulf of Maine cruise. He's gathering footage for a video about bioluminescence, and he's bringing the Gulf of Maine to your desktop as our @Sea correspondent. Click below to learn more about Brian...
|
|
|
|
Is there a question you'd like to ask our intrepid correspondent? Send us an email at
AskAtSea@hboi.edu.
Selected questions will be forwarded to Brian, and we'll post the answers online.
|
|
|
DISPATCH 5 & 6: Rock and Roll on The Big Blue Sea
@Sea correspondent/photographer, Brian Cousin
Phronima sedentaria a hyperiid amphipod collected in Oceanographer Canyon.
July 12, 3:30 PM --
The seas have been tossing us around all day. A line of squalls is blowing through, whipping up the water and sending waves pounding against our starboard beam. The sound has to be similar to hearing something big, like the family car, hitting the garage door at home. You want to jump up and find out just what on earth's going on.
Glassy blue-green waves crash over the railing, and the deck beneath the Johnson-Sea-Link is awash with seawater. Thirty-knot winds fan screens of spray off whitecapped waves. A few juvenile seabirds have taken refuge in quiet corners of our research vessel.
I can't believe we're in the same place as yesterday; sunny and warm, seas calm and inviting. But that's how it goes here in the Gulf of Maine.
Dr. Tammy Frank and Dr. Edie Widder made two scheduled submersible dives yesterday as their investigations into vertical migration gear up.
Already their observations are showing dense layers of animals at different depths corresponding to different light levels, and that the animals are migrating vertically. The species of krill they are encountering now are different than those found in the fall of two years ago, but seasonal population changes can be expected. What's important is that there are animals in ample numbers to make relevant observations with regard to the up-and-down population movement, as the down-welling light changes in intensity and color.
Tammy and Edie will refine their sampling schedule to conduct their shallower horizontal transects and deeper ones on alternate nights. It seems the deeper animals are taking longer to begin their migration, and limited by the amount of time the sub can remain submerged, the scientists are unable to witness the entire migration while making optimal counting/identifying transects. In essence they will halve the number of transects per night, while doubling the duration of each one.
Tammy also completed a second Tucker trawl at about 2:00 this morning. Testimony to the abundance of animals in the migrating layers, the trawl rendered almost 4,000 specimens after a two-hour tow. Future trawls will be significantly shorter in duration.
In other of yesterday's science activities, I joined Dr. Steve Haddock from Monterey Bay Aquarium Research Institute (MBARI) and WHOI's Dr. Sonke Johnsen in the first blue water scuba dive of the mission. Tethered to a down-line and outfitted with glass sample jars, we set about collecting tiny transparent organisms in the top forty-foot layer of surface water, 2,900 feet above the ocean bottom. The water is surprisingly warm and visibility excellent for our location, but it is the incredible blue vastness of the underwater open ocean that blows me away. I take a turn as safety diver while the others collect. From my position above them I watch as they work against a palette of deepening blues, keeping tethers untangled and an eye out for large predatory animals. We are in waters that are home to several species of sharks, including the great white.
Sonke will continue with his UV studies of the animals he collects. Steve is working at the molecular level: one of his goals is to clone photoproteins in the lab, of bioluminescent animals he collects at sea.
July 13, 7:00 PM -- No submersible activities have taken place today, the weather and seas are beginning to settle down. While that's disappointing for Edie and Tammy, there's already plenty of data to catch up on from the first dives. Edie is compiling numbers from the spectrophotometer in the aft compartment of the sub. Tammy has a hyperiid amphipod, Phronima sedentaria, on the electrophysiological prep, taking readings of visual sensitivity.
Of today's conditions Edie Widder says, "That's oceanography. We can actually use the down days to catch up, we would just prefer them later than earlier in the cruise".
|
|
|
