HECATE STRAIT 2015 Research Cruise September 28-October 12
Members of the Leys lab travelled to the west coast of British Columbia to study the sponge reefs using the remotely operated submersible ROPOS. Read about the trip and view the amazing reefs by videos - below.
IRLS log: Date: October 2, 2015 Dive: R1887 Objective: Calibrate Thermistor 14-15, Deploy SIP-1, Search for missing instrument SIP-3 ROPOS off deck ROPOS in the water ROPOS descending
The ‘In Real-time Logging System’ (IRLS) entries read like a science fiction-esque space journal, and at times it really feels like we work in a NASA control room. The main laboratory of the John P. Tully (a Canadian coast guard ship) is crammed with screens, joysticks, computers, and various unrecognizable gadgets and gizmos that only the expert ROPOS crew can operate. Our instruments line the starboard side of the lab, and are programmed and prepped for deployment by Sally Leys and Amanda Kahn. Meanwhile the ROPOS crew are surgically operating on their robot; removing probes and replacing them with others, fixing and modifying. The window for turnaround between dives is only about two hours, and while it may seem like a long time, the amount of work to be done leaves everyone working at maximum capacity. Once the gear is prepped and secured to ROPOS, the science crew gathers on the stern* to watch the lifting of ROPOS into the water. The deck is buzzing with radio static as the ROPOS crew ensures that the launch goes off without even a single hitch. Once the submersible is in the water, everyone assembles at their posts in the lab to observe, log and run the operations streaming live from the robot. As well as having multiple sensors, cameras, and samplers of various natures, ROPOS has two arms to manipulate the instruments that we loaded on deck. There is a miniature copy of the ROPOS arms in the command room, which are used as controllers for the larger ones. Considering our probes are incredibly sensitive (and even more incredibly expensive) they have to be handled with motherly care. The dexterity of the robot is a technological marvel, but the fragility of the instruments is challenging to work with and leads to nail-biting tension during the dives. It takes a huge amount of precision and expertise to operate a ROPOS submersible, and looks like the operation of a space probe. We are certainly glad to have a dedicated and patient crew working alongside ours.
Our tasks for today’s dive are to calibrate our flow thermistors (which are paired to oxygen sensors) against an acoustic flow meter termed “Vector”, test the functionality of a “SIP” water sampler, and find a missing SIP (if time permits). This, however, is just a backup plan so that our valuable time is not lost. Ideally we would be working in the Hecate Strait, west of Banks Island (Northern BC), but rough waters forced us to move closer to land, outside our study site. Once ROPOS hits the sea floor we start juggling the instruments, trying to make sure that each one of them is calibrated with the Vector for at least five minutes. These calibrations are invaluable, as they give us the numbers we will be using to assess the validity of our data, and need to be done carefully. The SIP worked perfectly, which was a pleasant relief from the delicate instrument work. After the calibrations were done and the SIP was fired, we had some time to look for a SIP sampler that was lost during a previous dive, “SIP-3”. We fly over the sea floor, eyes peeled. The gravel benthos appears barren, but looking closer there are countless polychaetes, corals, snails, anemones, bivalves, crustaceans, echinoderms and, of course, sponges. Although we did not find the missing SIP yet, it is a pleasure to explore such rarely seen terrain. As we take a moment to forget the time and effort that goes into studying life 150m below, we get the chance to appreciate the wonderful beauty and diversity of life, and remember what inspires us about what we do.
* “Stern is the back, like your spine is to the back when you are stern; bow is to the front like your back is when you are bowing down”-Lauren Law