Workshop woman

Friends, I described my ideas for experiments to start on this cruise as "half-baked," and I chose that word purposefully. It wasn't meant as an insult to myself but rather a true reflection of reality. There was limited opportunity prior to the cruise for me to meet with the ROV team about the underwater operations I wanted to complete, and besides, we're using a smaller ROV this year than previous years. I had definite goals and plans in mind, but I knew I was going to have to improvise. I basically showed up on board with a box of raw materials and have spent the first week trimming my samplers to the ROV's space and weight limitations. In terms of my baking metaphor, I showed up with batter and a selection of differently-shaped cake pans.

The cages and frames I built out of PVC
One of the items I want the ROV to plant on the seafloor are predator-exclusion cages. The rectangular cages are meant to keep predators like sea stars and fish away from some of the sponges that live on stones on the seafloor in the HAUSGARTEN, so that then I can come back in two years and see how the community has changed. The relative changes in the caged-off areas compared to control plots without cages should demonstrate the effect that predators have on the sponge community. I came prepared with PVC pipe and netting, but I had no idea what size the cages needed to be. After measuring the ROV's sliding drawer and testing a few options, I decided on a size of cage that worked well and set about building them. I could cut the PVC and the net by hand, so it was relatively easy.

The next items I want to outplant are larval traps and fouling panels. These devices have recently become a staple in my research. Some of you may remember I had deployed them on moorings in the HAUSGARTEN and in north Svalbard with help from my German and Norwegian colleagues and
recovered the first set of them last summer. The water-column traps didn't have many larvae, so I'm curious whether larvae in the Arctic might be dispersing closer to the seafloor (I'm actually hypothesizing so). The only problem? The traps were too tall to fit in the ROV's drawer. I had to cut them down.

One of my finished larval traps. Each column is a sampler
that will hopefully catch larvae, and the panels on the sides
are to see if anything settles and grows over the next 2 years.
The PVC I used for the larval traps was pretty thick, so I couldn't cut it with the tools I had brought. Thankfully, the ship has a well-outfitted workshop. I made my way to the lower deck, and thanks to some very helpful members of the ship's crew, I was able to secure a clamp, a saw, and some work space. I spent the afternoon sawing away at PVC, and I've got to admit, it was pretty satisfying.

I'm still fiddling with the traps a little to make sure they are easy for the ROV to handle, have enough weight to stay in place on the seafloor for two years, and will open themselves automatically after I leave them behind. Every day, I'm getting closer to a finished product, and I look forward to starting my experiments soon.

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