Dispatch: May 24, 2006

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Day's menu: Prime Rib!!, baked salmon, au gratin potatoes, mixed vegs, asparagas, cheesecake, carrot cake; Hamburgers, hot dogs, French fries, peas, rice, salad, and cookies.

Slip 'n' Slide at 0200 on the Lido Deck
Did somebody turn back the clock? Last night it got windy and sloppy out on the ocean again, and the rockin' has returned. It's not so bad that science activities need to be suspended, but there are magazines all over the floor of the Lounge again, and nobody's been there to be leaving them around. I found the mouse of a computer dangling off the desk and large chairs askew good thing the hardware is well lashed down. You know those waves and grey skies? They're baaaaa-aaaaack!


Large mesh sieve



I was on the Bridge last night, and although there were no icebergs, the white caps on the waves were certainly eyecatchers. "It's just a front blowing through, and we'll be happy again soon," says one crew member. Isn't that always the case? Well, last night's dredge yielded a most interesting haul. The Blake trawl (go to www.auburn.edu/antarctica to see the types of equipment we're using) was deployed sometime after midnight, and at 2 a.m. it was back on deck with a nearly solid block of mud in its net. When that happens, it is sliced off in chunks, and the mud is rinsed from the wildlife in series of different sized sieves out on the deck. "Size" refers to the size of the spaces or holes in the wire mesh at the base of a metal ring about the diameter and depth of a large cheesecake pan. They start with the large mesh and rinse through to a smaller and then again smaller one in order to 'catch' more specific things in it.

The large mesh might leave behind snails and sea squirts and stars, the medium is maybe for large worms and small crustaceans, and the fine mesh for things the size of krill and much smaller worms that have worked their way through the other two. (There are also a couple of very fine mesh sieves that the plankton group uses to trap the critters that can't be seen by the naked eye rinsed from their nets.) It's a very messy job, and this team gets right into it. Ladies and gentlemen, your sons and daughters are working very hard for their keep here.


Diego Giberto and Rhian Waller display one of the hazards of the trade.

Many starfish, several 'sea mice' (a kind of large, hairy worm really, you'd have to look away), and 3 small octopus were among the treasures in this haul. Quite a bit of diversity in these waters.

Let me tell you a bit about what it takes to deploy a piece of equipment or an instrument over the side of the ship. Naturally, everything that needs to be used again has to be attached to the back of the ship in some way. In the case of a dredge or net, it's attached by a cable. In some instruments, the cable includes a fiberoptic wire (if they're going to see something with it) or an electronic data wire (if they want some data to come back from it). There are huge spools of wire and cable on the decks for use in equipment deployment. The Chief Scientist meets with the Captain regularly to work out a strategy for the type of equipment he or she used (in our case, it's Ken Halanych and Marty Galster). They determine coordinates on a map where the sampling will happen, and the Captain relays that to the Mate who is at the helm of (driving) the ship, the Marine Technicians, Electronics Technician and the Marine Projects Coordinator. When the ship gets to that map point, it slows down or stops to perform the test. In our case, Ken usually does some diagnostic work to find out what the bottom looks like, to determine the best piece of equipment to send down to collect animals. Sometimes they use the Smith-MacIntyre grab that is dropped to the bottom and snaps shut like a mouse trap when it senses solid bottom. Ken gets to see what's at that particular square foot and makes an educated guess. Another way is to send down an ROV that has a camera that shows exactly what's on the bottom over a wide span of real estate. The ROV is great, but takes a much longer time to deploy and complete its mission.

All of this is simple enough (if you're a rocket scientist), given what we know in our own back yards, but out in the open ocean with wind and waves and current and 230 feet and 3780 tons of on-water shifting and bobbing steel and rivets with two giant whirring blades under it, there is a lot to consider. Everyone involved in a given operation has a radio and there is a lot of conversation between the Bridge, the deck technician and the aft Winch Control Room (oh, hadn't I mentioned that yet??). Once they know which piece of equipment is going over, the appropriate cable from one of those giant spools is run to the deck through a series of pullies and guides, and is attached (another artform) to the about-to-swim item. The winch operator runs the cable out (and in), as well as operating the movement of the A-frame that leads the cable up and away from the decks. The person at the helm has to maneuver the boat so that the equipment goes out behind the ship, and stays there throughout the entire operation, until which time it is hauled back up on the ship's deck, full of sea booty. It is like a well-designed traffic stop, only, it tips and sways and sometimes it's wet and slippery and cold as well. Nothing to it.

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Last updated May 23, 2006
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