We are pushing on to our last two seamounts, Sapmer Bank and Atlantis. Middle of What Seamount (MOW) was a very difficult site to work in. The boundary between sub-tropical waters and the sub-Antarctic was running right across the seamount while we were there so tremendously strong currents swept across the entire area. Our Remotely Operated Vehicle (ROV) was stuck fast to the seabed in several places, unable to move because of the water sweeping past. Despite our tribulations we did manage to glean enough information to get some idea of the life at MOW. We saw some of the famous orange roughy, the fish that live to 150 years old or more and which have been heavily targeted by the fishing industry. Very prominent were small lantern sharks. During many dives with the ROV glowing lights could be seen in the distance and these were the eyes or light organs of these strange animals swimming around in the deep. Other fish avoided them so they must be predators. We also saw areas apparently damaged by trawling, although unlike other seamounts there was no evidence here of lost fishing gear or trash. Some areas were simply breathtaking. Looming out of the darkness on cliffs of ropey lava were trees of bamboo corals over 2 meters in height. Elsewhere we found tremendously rich gardens of bright purple and yellow corals as well as large trumpet-shaped sponges smothered in bright red and yellow crinoids. Above and amongst the coral hovered oreos, another long lived deep-sea fish, with glowing yellow eyes and with a very characteristic swimming motion involving the undulation of the dorsal and ventral fins. This was a fantastic sight and again demonstrates that some of these areas are not completely destroyed. Management of fisheries in such areas is of all the more importance to conserve what remains of these striking but very vulnerable ecosystems.
We also had to contend with bad weather again over this seamount. The previous evening we had winds of more than 60kts and the sea rose fairly quickly to give everybody a poor night’s sleep. It even stopped us working for about 24 hours. Yesterday we were able to recommence with oceanographic measurements in the afternoon. Plans were changed again to accommodate the gap in work. This has been a very busy cruise for me managing a lot of shifts in work schedules for one reason or another. Everyone remains buoyant on board, and there is the looming prospect of finishing science and then steaming home for Christmas, something that everyone is looking forward to.
