The first MAR-ECO cruise to the Mid-Atlantic Ridge has been completed!
The RV Akademik Mstislav Keldysh with the manned submersibles Mir1 and Mir2 (Shirshov Institute of Oceanology, Moscow) have been working in the area of Charlie Gibbs Fracture Zone, 12 - 14 June 2003.
Two double dives were completed successfully on June 12 and 14. The dives were performed to 3000 m in a very rough area of the Charlie Gibbs Fracture zone. The third dive was cancelled due to a heavy storm. Mike Vecchione has sent us two short but exciting reports from the two dives.
13 June 2003
I just wanted to let you know that, after many days of steaming, we completed the first double dive yesterday- to 3000 m in the roughest area we could find. It was a good dive and everything went well. We saw, videotaped and photographed a lot of different kinds of fishes, as well as a cirrate octopod, shrimps, galatheids, and a variety of soft corals, feather stars, sea cucumbers etc. on the bottom. It turned out that the bottom is even rougher than expected. It is not at all trawlable. Therefore, direct observation by submersible is the only means of determining the occurrence of mobile epibenthic and demersal megafauna in the area.
Highlights so far: (1) the cirrate octopod, an opisthoteuthid which was encountered and remained in midwater, unlike expectations that species in that family mostly remain on the bottom unless moving from one location to another. (2) the occurrence of very many small rattails. Ray Wilson informed me that this is particularly interesting because macrourids of this size are not usually collected by either bottom or midwater trawls. (3) a small orange frogfish (benthic anglerfish). Although these have been videotaped from submersibles before, this dive dive recorded excellent videos of the animal walking along the bottom and swimming. (4) several sightings and an excellent video of an unidentified creature, possibly an enteropneust. Although this is not necessarily something entirely unknown, it is very interesting because it is difficult for an invertebrate zoologist to recognize and we have good images. Christopher Ralston has been working steadily on materials for public outreach. John Nicoals is working since we got under way also, but there doesn't seem to be much marine mammal action out here, at least at this time of year.
Here is the plan for tomorrow (Friday): We begin the second dive at 0900 and plan to be back on deck no later than 2200. The ship leaves the area as soon as the subs are on deck. There will be no dive Saturday, even though the Russians really wanted to contribute a third double dive. A moderately nasty storm is headed our way and should start around midnight Friday. We will be steaming straight through it to get to Newfoundland.
15 June 2003
Diving is complete and we are rolling through heavy seas, heading for home. I have had to take all of the drawers out of my desk because they keep coming out on their own during heavy rolls and rocketing across the room. The most dangerous part of the day, however, was the celebration of the successful completion of the dives. It was a Russian celebration. Many toasts with straight Moscow vodka. Afterwards, I wasn't sure if the ship was rolling or not.
The second double dive was most noteworthy in its contrast with the previous dive, although they were only separated by a few miles. Today we were on basically abyssal sediments with very few animals in sight. There were a few very large rattail grenadiers (Coryphenoides armatus) and some huge shrimps (an oxymoron), and some cucumbers but little else. Whereas the area of the first dive seemed to be a nursery for grenadiers, part of the area traversed by MIR2 yesterday appeared to be a nursery for elasipod holothurians. Andrey Gebruk, who is an expert on deep sea cucumbers, was quite pleasantly surprised. Everywhere throughout our dives, marine snow has been highly concentrated. Georgiy Vinogradov say it is the most that he has seen anywhere. Also we keep running into beautiful sponge gardens, as well as near-bottom concentrations of appendicularian houses. Both sponges and appendicularians filter feed on extremely small particles. There is also a lot of phytodetritus in evidence.
We have accomplished what we set out to do: complete the first MAR-ECO cruise to the Mid-Atlantic Ridge and conduct deep dives on the Charlie Gibbs Fracture Zone. We were also the first humans ever to visit this part of the planet.