Leg Two, Open Ocean to Inner Sea

Inner Sea to Open Ocean

Francoise Gervaise
Sep. 08 2013
Grabbing a tube for the next sediment core at the Strait of Georgia site.
Grabbing a tube for the next sediment core at the Strait of Georgia site.CSSF/ONC/SOI

It was hard to tell with all the fog, but as we made our way out of Saanich Inlet through Active Pass, we were threading a precariously narrow needle. Though sailboats avoid it, powerful ferries take this pass, coming close to the steep rock sides that we could only see in places.

Our first stop once we made it safely out, past a couple of tight turns, was in the Strait of Georgia. There we did a short ROV dive to collect a group of sediment core samples. We had to shift location a bit because when we arrived at the station, we found 20 or so fishing boats taking advantage of a newly opened salmon fishing zone.

Bottom Feeder Appreciation

Renald Belley slicing samples from one of the sediment cores.
Renald Belley slicing samples from one of the sediment cores.Mark Schrope

The cores were for Rénald Belley. He’s studying how animals in the sediment process food there and how quickly they use up oxygen. The overarching goal is to get a better idea of how these unassuming animals—lots of worms as well as small crustaceans and mollusks—affect the waters above with their activity.

As the sediment dwellers consume food they also produce carbon dioxide and other materials that make their way up to fuel animals in the water column and even algae toward the surface. “That’s the cycle that I’m looking at,” says Rénald.

The view leaving Saanich.
The view leaving Saanich.Mark Schrope

As he did with a few cores from Saanich yesterday, Rénald sliced off samples of sediment from different depths down the core to learn what animals are at each level and to run experiments with them. Specifically, he measures how much oxygen they consume and how much carbon dioxide they produce with and without the addition of extra algae as food.

Other cores he preserves for later analyses of the amounts of algae, carbon, and nutrients they contain. Ultimately he’d like to know how different animals affect the key processes, and how they respond to things like new pulses of food from algae blooms.

Heading Offshore

isgard Lighthouse after dropping off the pilots.
isgard Lighthouse after dropping off the pilots.Mark Schrope

By the afternoon, we were making our way on to the Juan de Fuca Strait, past scenic Fisgard Lighthouse. Soon after, we lowered a small boat to take the two pilots back to Victoria that had helped guide us during our inland work.

Then we were on our way offshore to the open waters 80 kilometers or so off Vancouver Island where we’ll be working for the rest of the expedition. After flat calm inland waters, the 20-knot winds and 2-meter seas were a significant shift. Tomorrow, the crew will calibrate our deep-sea navigation system, and then ROPOS should be back in the water by the afternoon.


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