CE 100014 Cruise Blog
Hi everyone, my name is Sharon Doherty and I’m a student studying marine science at the University of Ulster. I’ve joined the scientific party aboard the Celtic Explorer for 3 weeks to investigate the Irish cold water coral reefs. I am currently on my placement year from university and I will be counting this expedition towards it.
I am passionate about the marine environment and want to experience it in every way and learn as much as I can, so this expedition will help me do exactly that! My passion for the marine environment began at the age of 10 when I first took to the water, learning how to sail. Since then I haven’t looked back and my passion for sailing and drive to become a marine scientist has exploded.
The chief scientist aboard is Dr. Anthony Grehan from NUI Galway and the scientific team are from Earth and Ocean Sciences, NUI Galway: Anna Rengstorf, Inge van den Beld, Siddhi Joshi , Caroline Kivimae, Eoin McAleer; from the Institute of Zoology in London Zoo! : Chris Yesson and Kirsty Kemp; and myself from UUC . There are three Remotely Operated Vehicle Pilots: the ROV Super: Jim McDonald, Will Handley and Karl Briendensieck and our IT specialist: Paddy (McIvor) O’Driscoll.
The ship is captained by Denis Rowan and there are 14 ship’s crew in total (left). A French student from IFREMER got caught in the travel chaos associated with the volcanic ash cloud over Europe and sadly for him missed the trip.
The cruise is one of a series carrying out research for CoralFISH and another deep-sea project HERMIONE. The work over the next three weeks will involve surveys of fish in coral and non-coral areas, and animal collection using the Holland 1 Remotely Operated Vehicle (ROV); Conductivity, Temperature and Density (CTD) profiles and water samples to describe physical and chemical water mass characteristics in the sites that we visit. All this combined with the fisheries echo sounder transects over coral and non-coral areas to look for differences in fish abundance at these sites.
We left Galway Harbour 7pm on 19th of April, sailing off into a beautiful sunset. Our first site was located 250miles north-west of Galway, called the Logachev Mounds. These mounds lie on the margins of the Rockall Bank (left).
Steaming to our first location took over 24hours and we encountered a heavy side on swell. This forced me, and a few others to get our sea legs the hard way, and fast! Thankfully by the time we reached the Logachev area, we had perfect weather for conducting the very first (of many) surveys of the expedition.
On traveling to the location there was a meeting for all the scientists onboard to get to know one another, explain what everyone wanted from the expedition and how we were going to achieve it. We were then all spilt into our watches (teams) for the voyage. The two watches are the ROV crew and the CTD crew, which I am part of.
Work on board is carried out in two shifts of 12 hours. The day shift (8am to 8pm) is devoted to ROV surveys while the night shift (8pm to 8am) is predominantly used for water sampling with the CTD.
The CTD crew is made up of me, Eoin and Caroline (CTD boss). The CTD work involves the testing of both the physical and chemical parameters of the underlying water masses. From a physical perspective, sensors attached to the CTD rosette, allow the conductivity, temperature, and density i.e….CTD of the water column to be quantified as the rosette passes vertically through the water column. These data sets are then displayed graphically in real time on one of the Explorers onboard computers. Using these data sets it is possible to identify various water masses and other areas/depths of interest. At these depths bottles are fired, allowing water samples to be collected and brought to the surface. Once at the surface, the samples are tested for salinity, nutrients, organic and inorganic carbon, dissolved oxygen and chlorophyll, thus giving a comprehensive chemical analysis.
The aim of conducting this CTD sampling is to investigate the environmental parameters around cold water coral reefs and to establish a baseline to monitor ocean acidification.
Last week consisted of CTD dives and water chemistry sampling. These took place from the middle of the Rockall Trough, right along the Rockall Plateau. The CTD profiles have been from 2864m to 670m.
On the 22nd the bow thrusters on the ship developed a problem and accurate CTD dives were unable to continue so the sampling had to be abandoned for the night. Thankfully the crew got the problem fixed fast and the boat was back in action the very next day!
The first week has been challenging getting used to the working hours, the equipment and methodology. However by the end of the first week we all feel confident and are enjoying this experience.
A highlight of last week for the watch was getting to introduce myself to Oceanography and water chemistry for the first time! I am now even a functional member participating in site samplings!
The ROV watch operates 8am to 8pm to to allow daylight deployment of the ROV. In the ROV watch are; Anthony Grehan, Anna Rengstorf, Inge van den Beld, Siddhi Joshi, Chris Yesson and Kirsty Kemp.
Anna is responsible for producing all the dive maps and operating ROV navigation during dives; Inge looks after OFOP, a programme designed to help record information about what we see during the dive; Kirsty and Chris are sampling corals for genetic work, while Siddi aims to conduct a multibeam survey to map the Arc Mounds.
As well as the sampling, the ROV Holland 1 (right) has been conducting video transects. As these transects are conducted the images are viewed on a big screen in the dry lab. Members from the watch then try to identify the species of fish and invertebrate fauna that they witness. This is a very difficult task however as the image isn’t always clear and the species can flash by so fast.
Some of the species that have been identified last week were; rays, sharks, fish, octopi and much more. As the ROV travels along these transects it takes still images. Some of the images will be soon available in CoralFISH gallery.
The scary moment last week was when the ROV encountered fishing gear. If the ROV had gotten tangled it would have spelt disaster, thankfully the pilots avoided this!