Friday, August 5, 2011

Update 4 - bad weather and more fishing

arctic skate
For three days (28-30 July 2011), Cumberland Sound endured gale force winds. We hid at anchor in Pangurtung Fjord, and even there the winds reached over 30 knots. At one point, the ship started dragging the anchor (the type of thing that only happens in the middle of the night – I was asleep and missed it).

Shifting our plans slightly to get some work done, we deployed an acoustic range test in Pangurtung Fjord in the afternoon of 29 July 2011. Strong wind and tides made the deployment difficult as the ship struggled to get on top of each position accurately. Acoustic tags of different types were dropped into the water at known locations and moorings with receivers were positioned at specific distances away. The aim is to determine how well the receivers can hear the tags over a year. How sound propagates through the water depends on density which can be determined from a CTD cast. I did a cast over the range test and discovered the water in Pangurtung Fjord creates a very different profile (fresher and warmer near the surface) than Cumberland Sound water.

On 31 July 2011, winds died down enough to venture into the Sound. Before we left, two new scientists came on board and Aaron went home. Now we have one more scientist than bunks, so someone is sleeping on the floor of the lab on a pile of lifejackets – and it's not me. First we put out another shark fishing line then 24 moorings were deployed, most with receivers on them plus another group for a range test. I even squeezed in three CTD casts and downloaded all the data. I'm still seeing a temperature minimum around 100m. By the evening the sound was calm, so we drifted for the night.

We started 1 Aug 2011 by hauling up the shark line. Only three sharks took the bait and one escaped before we could get our hands on it. Two remained, one male and one female, both large animals in good shape. Nigel and Iva tagged both and released them. For the second one, in an effort to get a line around the shark, Nigel's nose rubbed the wrong way on the shark's skin, leaving him with bloody nose rubbed raw.

I finally got to build my first oceanographic mooring. It was deployed as soon as we were done with the sharks. The mooring went out in 270m of water, the mooring itself was 240m long with conductivity and temperature sensors spaced every 40m. Also, attached at the top was a dissolved carbon dioxide sensor for someone else's project (the sensor came in a wooden crate held together with star shaped screws – with me I have a screwdriver for almost any type of screw out there, except that). I've never worked with a carbon dioxide sensor before, so I checked the manual on how to deploy it. According to the manual, the sensor was ready to go and I could check that by waving a magnet over a red dot on the instrument's side, waiting 40 seconds, then looking for drips of liquid coming out a tiny tube. I saw the drops, so I'm assuming the instrument is ready to go. This mooring will be recovered at the end of August, the data downloaded, then re-deployed for the winter.

The second of August was another sunny, calm day. First thing in the morning we pulled up a long line of hooks we deployed the night before – I think there was 300 hooks total, each baited with squid. Right of the bat we had a shark and eventually we caught two more and each of them were tagged. We also caught our first arctic skate. When a skate comes out of the water, it curls up instinctively. When I saw this the first time, it looked exactly like the creature that fixed itself to the face of one of the crew members in Alien. In the end, we caught many skate and only two turbot – the first turbot was too small to tag, so only one turbot got tagged.

On our way to the next site, I was able detour for a CTD cast between two islands. As we did the cast, one of the crew members told me there was an old whaling station on one of the islands (Kekerton) along with a cemetery. I couldn't see any structures on the island from the ship, however, the whaling station was marked on the chart. It would have been nice to anchor near by and take a look around.

A sailing vessel with two masts passed us, along with two tug boats hauling barges. I was told the tugs were dropping off their loads at a mine up the sound – apparently, they are mining for diamonds. One of the tug boats was named 'Molly', a fact I learned listening them call on the radio (I never heard the name of the other tug or the sail boat).

The third and fourth of August blurred together as we spent the days fishing with a few CTD casts in between. It was one of the crew member's birthday so, Iva and I conducted a chemistry experiment by baking a cake based on what we could find on board – a number of substitutions were made, luckily resulting a tasty coffee cake. It's very difficult to covertly bake a cake on a small ship, no matter where one goes on board you have to pass through the galley. We managed because the captain put the birthday boy on bridge watch while we were mixing everything together. Later as the cake baked, we were all on deck working with the fishing lines. Another scientist pulled the cake from the oven and stashed it in our cabin (making for a nice smelling cabin). Iva planned in advance and had birthday candles on hand and we lit them without setting fire alarms off.

Swell came in and the winds picked up forcing us back into Pangurtung Fjord for the night of 4 August 2011. A crew swap will occur and we'll be changing focus next week – the shark wrestling phase of this expedition is done.

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