While Graham Tulloch was on deck tackling the challenges associated with programming and attaching the equipment for the landers, I was preparing for my ATLAS role in the expedition.
The two sites at which the landers were to be placed were chosen to be in contrasting locations in Southern Baffin Bay. A ‘non-sponge site’ was chosen at SE Saglek bank, where very few sponges have been brought up in nets, while another ‘sponge site’ at NE Saglek bank has lots of sponges including Geodia, Asconema and Polymastia sp. and some soft corals such as the stunning red tree coral Primnoa resedaeformis. Both areas are within an area of Hatton Basin where bottom fishing is not allowed in case it damages these fragile creatures.
Red Tree Coral Primnoa resedaeformis Credit: ArcticNet, 2016
Our main aim is to understand what type of food is arriving at the sponge grounds and coral reefs and how it gets to them. When we collect Graham’s landers next year the information from them should help us answer this question. The landers have pieces of equipment attached to them that will give us some valuable long-term data. One of these is called a sediment trap that captures ‘marine snow’ that falls down through the water column. This is made up of organic matter, dead and decomposing sea creatures, animal poop, dust, silt etc. and is an important food source for all types of deep-sea life. Another piece of equipment will give us information on near-bottom currents that move the food around near the sponges and corals.
My concerns were very much in the ‘here and now’. On the ship, I was to be sampling the organic matter and exploring how food was spread out in the water column. To do this, I took measurements in two lines, each with five sampling stations, across the lander sites.
My lab was in a big converted shipping container on the port aft side (that’s the left side of the ship towards the front, when facing forward) of the helideck. I found the boxes with my lab equipment, the chemicals that had been sent from the University of Liverpool and NIOZ (Royal Netherlands Institute for Sea Research) and other special chemicals for preserving the samples that David Coté from Fisheries and Oceans Canada had kindly organised. Then I began setting up the equipment and labelling innumerable vials of various sizes to get ready for the challenge ahead!
Along with landers and ROVs, a very useful piece of equipment used by scientists at sea is the ‘CTD rosette’. CTD stands for conductivity, temperature and depth (the conductivity will tell us how salty the water is). It can be lowered into the water and set up to sample at different depths. Before joining the expedition, I’d been in contact with the chief CTD rosette operator, Pascal Guillot of Amundsen Science, so he knew in advance which depths I wanted to sample at.
Deploying the CTD rosette © Sabena J Blackbird
I put on my ATLAS beanie hat, sat in the CTD operator room with Pascal and his assistant Solenne Caous and watched the Amundsen crew deploy the CTD rosette at the first Atlas sampling station: ‘Sponge Site 5’. The first site was quite shallow (299m from the sea surface to the seabed), and it was not very long before the CTD rosette was on its way back up. Pascal used the controls on the computer to open specially designed bottles to collect seawater at the required depths. When the CTD arrived at the surface of the water, the crew expertly moved it back onto the deck and secured it down. After checking the CTD log sheet I pulled on my purple rubber gloves (looking rather gothic!) and began filling up two nine-litre containers for each of the five sampling depths. A number of volunteers very kindly helped me carry them around to the lab – special thanks to Alec Aitken, Robert Izett and Anirban Chakraborty.
Then began the filtering frenzy! Vacuum filtration onto filter paper for POM (particulate organic matter) and pigments; filtering seawater into vials for DOM (dissolved organic matter) and inorganic nutrients (Nitrate + Nitrite, Nitrite, Silicate, Phosphate and Ammonium). I also collected seawater to sample phytoplankton and bacteria & viruses - each requiring different preserving chemicals. The samples then had to be cooled before flash freezing in liquid nitrogen.
I had barely finished the lab work and placed the filters and seawater vials in various freezers before we were at the next station. The pattern was repeated for the next few days and nights until I managed to grab a break between stations. Meanwhile, the other scientific teams aboard were kept equally busy.
Northern Fulmar © Sabena J Blackbird
The well-earned break gave me an opportunity to peek out of the lab door to observe the Northern Fulmars who were dedicated followers of the Amundsen throughout the voyage, gliding over the surface of the sea on their stiff wings. There were even a couple of hitchhikers that landed on the helideck - a White-rumped Sandpiper (possibly on migration) and a Pine Siskin, which happily twittered away. We were also lucky enough to see (from far away!) a Polar Bear that flumped from an ice patch into the sea, strongly swimming into the distance and some Long-finned Pilot Whales and Fin Whales.
After completing the remaining ATLAS stations, we steamed across to SW Greenland to a Lophelia pertusa site discovered accidentally in 2012 when a piece of coral was caught on a CTD rosette frame during water sampling activities. ROV operators from the Canadian Scientific Submersible Facility faced challenging conditions. There was a high sea swell and strong currents but they managed to investigate the steep bedrock where the Lophelia pertusa colonies were found, between 750 and 950m deep. The video images displayed on TVs in each cabin also showed many different soft corals, sponges and fish.
Although the ATLAS team weren’t scheduled to sample the water here, it was too good an opportunity to miss! In George Wolff’s Organic Geochemistry lab at the University of Liverpool (where I work), we normally analyse the suspended particulate organic matter (sPOM) in the water. Unfortunately, the SAPs (stand-alone pumping system) that we use to collect sPOM from large volume water samples wasn’t available for this cruise. Instead, I used a smaller scale version of the SAPS and collected many samples. This new information will be added to what we already know about sPOM from different locations with and without Lophelia pertusa coral in the NE Atlantic.
Graham awaiting his fate in Neptune’s realm © Sabena J Blackbird
‘All work and no play’ the proverb goes. There was certainly going to be some fun, as many of the scientists were going to be crossing the Arctic Circle for the first time. Those people, myself included, needed to endure a number of challenges over the course of three days and be thoroughly tested by King Neptune (and his missus) before being allowed into the Order of the Blue Nose!
By Sabena J Blackbird