Life Aboard Ship, Dispatches From South of the "Roaring Forties"
May 19, 2004 23:00 GMT
It's 2300 GMT (four hours later than Eastern Standard Time of 1900) and we are now at 54 degrees 27.5 minutes W, 60 degrees S, 400 miles and two days out of Punta Arenas, the temperature is 5.4 Celsius (wind chill is 8 C) [Note: 16 F and 17 F], wind speed is about 9 knots. Yesterday we spent having cruise organizing meetings and setting up equipment. Today we started sampling after we got on station around breakfast. First, we ran bottom profiles to find an area smooth enough to trawl with our gear. Then we made a grab to see what the bottom was actually like (what is the bottom? Rock, mud, sand? What invertebrates live in and on it?), and after that we made two trawl tows at the relatively shallow depth of 90 meters. We didn't get too many fish in either one, but did get enough for the physiologists and biochemists to start their experiments, and for the invertebrate specialists to whet their appetite for more samples. We captured a fair number of what they call " king crabs" down here, although they are not as big as real king crabs from the Bering Sea. And, best of all, I got two small specimens of liparids, which are being preserved and which I will study and try to identify in the next few days.
Identifying a "king crab," are scientists L. Christoph Held, University of Bochum, Germany, and R. Paul Brickle, Falkland Islands Fisheries Officer.
We just finished setting eight traps for whatever we can catch. These are large mesh baited pots about 5 feet in diameter and two feet high, and are particularly useful for collecting larger critters that avoid or escape trawls or are not very common. They will "soak" or remain fishing, for 24 hours, and be picked up tomorrow at about this time. By using bait, we can catch a different selection of animals, especially some that either avoid our other collecting gear or are too uncommon to be easily caught. There really isn't any "perfect" collecting gear. All equipment has flaws and biases related to size of individual captured, number, attraction or repulsion of animals, and other factors.
So we will use a wide variety of methods to try to get the best picture of the animals we are studying as we sail across the South Atlantic. These include otter trawls (nets held open by doors, or paravanes on each side and dragged across the bottom); traps; grabs that sample the sediment and the animals in it; corers that do the same but take a sample more useful for relating bottom sediment type to animal occurrence; "light traps" that are held up in the water and are internally lit to attract small fish larvae and other animals attracted to light at night; and small midwater trawls to collect somewhat larger midwater animals.
Before the cruise, I decided that because I had never been in this part of the world, I would develop my interest in everything, including the birds (I have never been notably interested in bird watching). So I bought a good field guide and a new pair of binoculars and in my spare time I have been learning to identify the birds we see from the ship. I am fortunate in having two very good teachers, both of whom are expert in identifying Southern Ocean birds. One of them is an American, the other is a German, and as cruises usually go, folks who have never met find they have many common interests in natural history (after all, everyone in the scientific party has great interests in the sea and nature). Although I have seen albatrosses before in the North Pacific and North Atlantic, there are many more species down here. We have seen five species to date, including a wandering albatross, which has the longest wing span of any existing bird. It's a good thing I am using digital cameras on this cruise because I have missed dozens of shots trying to get good photos of them!
For the duration of the cruise we will stand six-hour watches; each watch has five scientific crew members to process the catch in addition to doing their own research, which for the duration of the watch, is of secondary importance. Work of mutual importance comes first. We are fortunate to have a large scientific party of 32, because it means that we can set a watch schedule that is not difficult. On many cruises, watches are stood 6 hours on and 6 off. We chose to each stand one six hour daily watch, which divides the day naturally into midnight to 0600, 0600 to noon, noon to 1800, and 1800 to midnight. We have four "watch chiefs", of whom I am one (I initially got the noon to 6 watch). We will rotate the times every couple of weeks so that everyone gets the least and most convenient times.
The weather has been particularly fine; it was pretty calm when we exited the Strait of Magellan, and actually laid down some more after we came out, much to everyone's surprise. I would say it is a 2-3 foot swell. It has been very comfortable sleeping, eating, and moving around. We're sure to pay our dues, however. In the winter, this is one of the roughest of oceans. When we planned the cruise, we assumed that we would lose some days to bad weather and therefore this loss will not cause significant damage to our research. Now it's time to go do some work, so that's it for this bulletin.