In keeping with the general tempo of this trip, the last day of research was not without drama. The ROV was making its last dive to the deep recesses of the Celebes when ROV operator Toshi sensed a strange drag on the vehicle. His thrusters were whirring, but the vehicle was not responding as it should. The clump weight, which is part of the deep sea ROV system, had become entangled in a line. Becoming tangled in the deep sea is the worst scenario for a manned submersible or an ROV. Stranded submarines entwined in line have been responsible for people's deaths. This happened off the coast of North Carolina with a Johnson Sealink submersible several decades ago. I dived that submarine several years after the tragedy. Many ROVs have been lost when they became entangled. It is very difficult to free a vehicle at depth.
The ROV's dramatic rescue
We almost lost the one million dollar ROV that night as the Celebes made one last attempt to keep yet another piece of our deep sea research gear.
The lights are now off in the ROV control room, the last sample jar is sealed, the jellyfish kreisels are disassembled. Mike Cole has stored the RopeCam accoutrements, Nick Loomis and Cabel Davis are taking apart the lasers used to create holographic images of plankton, and we are packing as the last wake of the Presbitero from this expedition forever fades into the deep waters of the Celebes Sea. We have completed our exploration and are on our way back to Manila.
As we cruise again through the Sulu Sea, we are organizing information and just beginning to understand what we have learned. It will take months, even years, to process the samples and analyze all the images and video. We all feel privileged to have been able to explore the deep ocean at the very center of marine biological diversity.