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Showing posts from June, 2022

Dragonflies: part 2

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When we got back to land, the first thing I noticed was I noticed was the dragonflies. Once again, they were fluttering around  Sea Scout 's working deck, gracing our world with their iridescence.  M/V Sea Scout at the dock in Louisiana. Photo by Calvin Mires. It felt weird to wake up and find the ship motionless after a week rolling around at sea, but we returned victorious to Intracoastal City, Louisiana. This project is actually a dream for me, because we put in equal effort on the shipwrecks and the hard bottoms. We collected data from seven sites total - four shipwrecks and three natural reefs. Usually, my datasets are either all shipwrecks or make just a passing effort at documenting nearby hard bottoms. This time, I have nearly equal data from both. Moreover, the reefs we looked at were the closest natural hard-bottom sites to each shipwreck. Two of the shipwrecks were equidistant from the same hard bottom, so I can actually do a one-to-one shipwreck-reef comparison. How do

Mystery in the mesophotic

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Our goal for this project was to document three shipwrecks and associated hard-bottom sites - that was the bar for success. By the end of the day on the Hamlet , we had reached that bar, and we still had an extra day at sea. We transited a few miles back toward land and set about investigating a new shipwreck.  Sonar image of the unknown wreck  The mystery wreck looked like a fishing vessel from the sonar. There were doubts that it would be historically significant, but it still represents an important component of the Gulf coast's Blue Economy: fishing. As the ROV descended, we could see the shipwreck's bow come into view on the sonar. The metal V-shape was clear, even through the murky water. As we approached, the organisms living on the wreck came into view. There it was: Tubastraea coccinea , the orange cup coral. Tubastraea coccinea is not native to the Gulf of Mexico. It comes from the Indo-Pacific and has spread across much of the Gulf and Caribbean since its arrival. I

The Hamlet

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Our dives today were focused on a shipwreck named Hamlet . The Norwegian oil tanker MV Hamlet was transporting a load of crude oil from Beaumont, Texas to Liverpool, UK in 1942 when it was struck by a torpedo from the German U-boat U-753 in the Gulf of Mexico. Along with the CP Baker , it's one of the historically-significant wrecks we're investigating - and another one associated with the oil and gas industry. This photo is from a reconnaissance last year, when the visibility was much better. Check out the corals on that gun! The dive on the Hamlet did not go perfectly, I have to admit. For a start, the visibility was horrible . We had actually encountered the "murk layer," as Evan calls it, during our dive on the hard-bottom site earlier that morning. It was impossible to see anything unless it was directly in front of the vehicle. Just brown, turbid soup.  We found the shipwreck thanks to the magic of sonar and approached it from the stern. Of course, we didn'

CP Baker

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Yesterday was an amazing day. We had a little touchy conditions in the morning - swift current, some waves - so we delayed launching the ROV until right after lunch. Once we got in the water, though, oh man, did we find cool stuff.  My sea fan (or black coral?) specimen We started on the hard-bottom site. It was a little knoll in the middle of the mud. We started at the bottom of it and worked our way up the slope, past rocks with crustose coralline algae, encrusting sponges, and sea fans. I'm not actually sure about that last identification - I've been calling it a sea fan, but it might be a black coral. One thing is for sure: it is everywhere. The ROV doesn't have a manipulator arm to collect specimens, so I was starting to disparage my ability to identify the species. As it turns out, no manipulator arm was necessary! The ROV's thruster got some strands stuck in it, so I was able to save the specimen for identification later. I'm excited to do the full analysis b

Wreck and boulder patch

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We have done it! We had a successful dive yesterday and were able to collect data from both a shipwreck and its nearest natural hard-bottom habitat.  Sonar image of the shipwreck and the hard-bottom site. I was the scientist in charge for the hard-bottom site. I sat beside the ROV pilot in the shipping container that serves as their control van on the deck. Radio in hand, I communicated with the navigator up in the lab, the captain on the bridge, and the pilot beside me. We surveyed the site by flying over it with the ROV and collecting video. We really weren't sure from our preliminary sonar data what we were going to find at the hard-bottom site. It just looked rough - it could have been mussels, rocks, or just clumps of mud. It turned out to be basalt boulders that had probably ended up on the seafloor through a geological uplift.  There wasn't a ton of stuff living on the boulders, but then again, we were pretty deep - about 80 m. I noted crustose coralline algae, some oran

Shakedown

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Preparing to deploy the ROV on Sea Scout. The vehicle itself is in the cage, and they're  both lowered over the side with the winch.  In ocean science, we frequently refer to a "shakedown." It means the first attempt at something, when you identify all the problems and get your procedure set. Well, yesterday was our shakedown on the Sea Scout .  The day started with the ROV team and videographers working together to integrate their systems. As I mentioned, the ROV we're using isn't typically used for research, so we added an extra camera for data collection at higher resolution. Whenever you try to integrate systems, there will inevitably be a thousand tiny things that go wrong and have to be addressed, and that was definitely the case yesterday. It took a long time.  My major goal for the day was to get the ROV wet - just put it in the water, I didn't care how deep. We were eventually able to dive in the evening, although that was a shakedown of its own. The

Dragonflies

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My favorite thing about the South is the bugs. No, I'm not talking about the mosquitoes that swarm around your head or the flies whose bites hurt as much as they itch. I'm talking about lepidopterans. I'm talking about coleopterans. I'm talking about arachnids. You know - arthropods. There is such incredible biodiversity in the southern United States.  Dozens of dragonflies flitted around the ship. Their long, needle-thin bodies gleamed and glimmered in the sunlight. A brown-and-white-striped spider darted out from under a box and caught a moth to munch on. A beetle climbed the side of the ship as I ascended the ladder. A large grasshopper rested atop the bow spotlight at dusk.  MV Sea Scout in Amelia, LA. Photo by Calvin Mires. Friends, I am in on board the MV Sea Scout  in rural Louisiana. When we arrived, the ship was unassumingly parked alongside a grassy field in a bayou. It was a rather surprising place to find a ship, if I'm honest. Calvin and I boarded, go

Time series

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It's hard to believe I've already been home from Palau for three weeks. The first week was lost to sleep - ask my husband, I was a lump. The second week was mostly paperwork and digging myself out from under the mountain of things that had accumulated while I was away. And now, here we are.  It is definitely summer. Woods Hole is full of tourists, and all the visiting scientists at the Marine Biological Laboratory down the street from WHOI are noticeable around town with their signature teal lanyards. WHOI has its own summer crowd too, although they're not quite so numerous or conspicuous. I actually have a summer student of my own this year, named Kimberly. She's a Cell and Molecular Biology major at the City University of New York, and she's been wonderful to work with so far.  Kimberly's project is an investigation of temporal patterns in an Arctic deep-sea community. She's actually continuing a project that I worked on back when I lived in Germany 10 yea