If you’ve been following the Deep Links website and Twitter feed then you must have stumbled upon many deep-sea pictures and videos, including the Sea Pen versus ROV video and some incredible deep-sea coral gardens. All these images are possible thanks to an intricate piece of machinery on board the RRS James Cook: the Remotely Operated Vehicle (ROV) ISIS.
This advanced underwater robot can dive to depths of up to 6500 m and is enabling us to explore uncharted seafloor territory. The vehicle is tethered to the ship by a 10,000 m steel cable enabling it to move around on the seafloor whilst remaining attached to the ship. ISIS is also fitted with two mechanical arms: Predator and Titan 4, which are controlled from the ship by qualified ROV pilots who sit in the “ROV shack”.
The first time I stepped into the “ROV shack” it was like walking into a scene from The Hunt for Red October. The dark room is illuminated by a wall of large plasma screens on one side and by an iridescent red light on the other. This large steel container is roughly separated into two sections: one for the scientists and the other for the pilots and engineers.
During each dive, ISIS is lowered into the abyss and the initial epipelagic blue gradually darkens as light slowly fades away. A descent to 1200m takes the ROV about an hour and a half but it would take considerably more to reach its maximum depth of 6500 m. Of course, the descent has to be monitored at all times and this means staring into plain blue water for a few long hours; it quickly became clear why the ROV shack had so many great playlists at hand! Unlike Mark Watney in The Martian, we never got tired of the 80s disco music.
Then, as the depth meter gets closer to the expected depth for the dive, the ROV slows down and gets ready to land. In some areas it can look as though you’ve just landed on the moon, with a never-ending landscape of sand and not one live animal to be seen. In other areas, you can be spoilt for choice as to where to look. We’ve been to places, such as the 1200 m site at George Bligh Bank, where the seafloor is packed with sponges and corals of all shapes, colours and sizes. One of my favourites is the Bubblegum coral, which could not have been given a better name as it genuinely looks like it belongs on the set of Charlie and the Chocolate Factory.
Once the correct depth is reached, the main part of the dive can then start and as ISIS hovers over the seafloor, five different cameras fitted with powerful lights are all streaming at the same time to ensure all angles are covered. One lucky scientist gets to sit at the front with the pilots to control the science cam. This has been one of my favourite experiences on this research cruise. Not only do you get to sit at the pilot’s table but you also get a joystick to control the camera and explore parts of the ocean floor that have never been seen before. Its pretty much like watching Ocean Planet live and what’s more you get to decide where to look next!
Thanks to this ROV, the potential for what deep-sea research can achieve has increased significantly. We can carry out sediment cores, choose what samples to collect, such as sponges, corals, sea cucumbers and urchins, and bring them back to the surface to be studied. We can also conduct video transects to determine the state of the ocean floor in Marine Protected Areas (MPAs). At some sites, for example, we observed over twenty different forms of fishing and trawl gear; be sure to read the previous blog on human impacts by Kirsty McQuaid for more info.
The images retrieved from the deep are not only important for research but also for raising public awareness about the state of the ocean floor. We have very little knowledge about what is down there and it is sometimes falsely assumed that it is a barren land of rock and sediment. The images we retrieved, however, demonstrate that this couldn’t be further from the truth. This is why the ROV ISIS is critical on projects like Deep Links to turn on the lights in the deep sea and give us reasons to ensure its persistence.
Text by Nina Faure Beaulieu, University of Oxford.