Amazing people and unfortunate crabs

It is common to get superstitious at sea. So much of our life on land is under control that the sudden feeling that you are small and at the mercy of these huge processes can come as a bit of a shock. Even the most logical minds can ascribe lucky and unlucky traits in a desperate attempt at making sense and taking some control of random and uncontrollable events.

We have been marred by misfortune at every turn and it is beginning to feel that there is some malicious and deliberate opposing force that is pushing against us. When you are just a few people, tiny against the forces you are up against, there is only so much you can have control over. This is the point where people really prove themselves however.

I am immensely proud of the people on this vessel, of the things they have managed to achieve with so little. Things have been forced to happen, have come into being through sheer acts of will: Deliveries that would have been late have been intercepted in transit (optional scientist as Adam Ant in Stand and Deliver sequence here), a -800C freezer has been found on a remote island and a abyssal depth rated vehicle has been constructed out of spare parts on the vessel, to name just a few.

These acts have yielded rewards. We have seen a slow trickle of data from the trench as we refuse to be beaten. The water is incredibly clean, allowing us to see our gear as far as 20m below the vessel. These clean waters don’t produce much life and so there is very little food raining down on the seafloor below. The photos we have taken have revealed a very clean seabed with golden silty sediment. In some areas there are large and irregular rocks lying on the sediment. Since they have not been burred they must have arrived relatively recently. Their dark colour and irregular shape would indicate they are volcanic in origin and we have seen a few signs of activity in the area.

Yesterday we passed over a ring of bright yellow/green water, in stark contrast to the clear dark blue of the surrounding water. There was a strong sulphur smell and also large amounts of pumice in the water; rocks that had solidified so quickly when contacting that cold ocean water that they were full of gas bubbles and floated on the surface. We have seen these floating blocks the size of footballs. These larger blocks become little floating islands as larvae in the water settle on them and grow. Many are covered in goose barnacles and we even recovered one piece with two crabs living on it. These were crabs that should have been living at the bottom and were not able to swim. They had obviously found their little island home as larva and grown there; if they were ever to fall they could never get back. The pumice is eventually over-colonised and sinks, likely killing all onboard. On a tough day in the middle of the ocean you can dwell on that. It can be a grim metaphor for all sorts of things. Poor little crabs.

We have covered a range of some 5,000m depth but the life we have found has been amazingly consistent. The same four fish species, in different proportions, have been found at all of these depths. These species are familiar; we found them in the Kermadec trench earlier this year. The Kermadec is closer to land and has a higher food input. In that trench we saw many species and several transitions with depth as one species took over from the last. Here in the New Hebrides trench the fish that we saw at about 4-5,000m in the Kermadec have expanded in both directions. This would suggest that in the Kermadec they do not occupy their narrow depth range because that is the only range that they can cope with but, at least on one side of their range, they may be limited not by depth but by competition with other species. The boisterous and greedy macrurids (rattails) may keep them out of the shallower areas in the Kermadec trench but here, with the noticeable lack of this group, they are free to spread and eek out a meagre existence on a seabed with very little food.

There have been a couple of species that have been mocking us for some time. Turning up in abundance for our cameras but refusing to enter a trap and allow us to know for sure what they are. Our deep-sea bullies were a large red shrimp and a very pale eel. We had our hunches as to what they were but without a specimen to look at it was all an educated guess. We have finally managed to capture a few examples of each. We have identified them as best we can on the vessel but in some species x-rays are needed. These specimens were left intact and will be examined at the Te Papa museum in Wellington. I am excited to finally put a name to the face that has been mocking me through a camera’s lens.

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