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Showing posts from June, 2018

To settle

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Friends, as I've mentioned, there are some experiments going on in my lab at WHOI right now to examine how oyster larvae behave in different environmental conditions. Students and interns in the Mullineaux lab have been working on oyster behavior for several years now, in an effort to understand how turbulence, light, and water chemistry affect the swimming behavior of oyster larvae. This mess of tubes is channeling compressed gas into our flasks of seawater.  This year, our question is how ocean acidification influences the behavior of oyster larvae when they're ready to settle and begin adult life on the seafloor. Settlement is a critical stage in the life-cycle of marine animals, and swimming larvae use a variety of physical and chemical cues to select the best place on the seafloor to attach, metamorphose, and spend the rest of their life. However, as the concentration of carbon dioxide in the atmosphere rises, more and more CO 2  is becoming dissolved in the ocean,

The hatchery

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Friends, while I was out diving last week , other members of my lab were undertaking their own experiments. Some of you may remember the oyster research that has been conducted in the Mullineaux lab over the past few summers. When I first started here, I was responsible for analyzing some of the data from past oyster experiments, and I submitted a manuscript for publication based on that analysis. Then last summer, one of the interns conducted her own experiments  to examine how oyster larvae behave in different environmental conditions.  Algae tanks at the Aquacultural Research Corporation. Photo by Brooke Torjman. Well, this year, we're at it again, exposing oyster larvae to a range of conditions in the laboratory and observing how they respond.  The first step in the experimental set-up is to obtain larvae, and for that, I was sent on an expedition of sorts - a field trip to the hatchery.  The oyster larvae we use in laboratory experiments are supplied by the Aquacultura

The voyage of the Dawn Treader: part 4

I felt a tap on my knee and opened my eyes to see Evan standing in front of me. "We're about 30 minutes out from the next site," he told me. I nodded. I was still a bit queasy, having gotten seasick after our last dive. Slowly, I pulled myself up and walked out on deck, keeping my eyes to the horizon the whole time. I actually felt more stable than I expected. I can do this , I thought. We rolled over the side of the boat and made our way down the line to the seafloor. The first thing I noticed were the sand dollars. Hundreds, thousands of them were scattered on the sand all around me. I swam forward, following Evan, and found the shipwreck. The Josephine Marie is a fishing boat that capsized off of Provincetown, Massachusetts. It lies upside-down on the seafloor, "turtled" as divers call it. Evan immediately began driving my samplers into the sand near the wreck, and I swam up to the hull to start scraping off adult specimens of my study species. I'm

The voyage of the Dawn Treader: part 3

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"No one except Lucy knew that as it circled the mast, it had whispered to her, 'Courage, dear heart,' and the voice, she felt sure, was Aslan's, and with the voice a delicious smell breathed in her face." - C.S. Lewis in The Voyage of the Dawn Treader My study sites and the Dawn Treader route. White outline shows SBNMS. Base map from Google Earth. Friends, the day has finally come! The project that I have been preparing for so long has finally begun! All of the preparations , all of the  dive training , and all of the practice deploying my samplers  are finally paying off. I had a successful day out on the Dawn Treader  and visited two out of my three study sites to set the project in motion. My study sites for this project are in Stellwagen Bank National Marine Sanctuary, a marine protected area just offshore of Cape Cod. The area is best-known as a productive fishing ground and prime whale-watching site (we actually saw a juvenile humpback), but the

Limpet Land

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Summer is quickly ramping up at WHOI, and that means experiments are starting! I set up an experiment on Friday to look at the effects of slipper shell limpets, Crepidula fornicata , on subtidal fouling communities. This work builds on the experiments I did last summer . My experimental panels with live limpets or shells Last year, I noticed that tiny slipper limpets settled on my panels along with the other sessile organisms . The limpets crawled around on the panels, each in the small area near where it had settled, and bulldozed recruits of other species as they went. The end result was that no sessile species could grow on the panel in a limpet-affected area, so there were halos around each of the limpets. The halos were cleared by bulldozing limpets, but they didn't stay clear for long. One species of ascidian , Diplosoma listerianum , colonized all new space on the panels, including the halos, and it even grew over the limpet shells. It was a strange sight to see a li

The voyage of the Dawn Treader: part 2

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"My own plans are made. While I can, I sail east in the Dawn Treader . When she fails me, I paddle east in my coracle. When she sinks, I shall swim east with my four paws. And when I can swim no longer, if I have not reached Aslan's country, or shot over the edge of the world into some vast cataract, I shall sink with my nose to the sunrise." - C.S. Lewis in The Voyage of the Dawn Treader Friends, it's another weekend, and Carl and I were at it again - dive training, that is. We reprised our search for the wreck of the Corwin in Buzzards Bay, this time with much greater success. The  Dawn Treader was smoke-free , so we made it to the wreck and had a wonderful hour-long dive. Our day started at 6 am. The low tide was predicted to be around 10 and we wanted to dive when the current was slack (about 9:30 - 10:30), so we got ourselves up and moving in plenty of time. The catch? The Dawn Treader is parked on a mooring in a marina, out in the middle of the water, and

Pilot

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Friends, every scientific study requires funding. And very often, obtaining funding requires a proof of concept. Funding agencies want to know that the study they're investing in will produce good results, so they need to see a demonstration that your plan will work. It's like the old adage "You have to have money to make money" - in science, you have to have data to get funding to get more data.  Slipper limpets on panels. I've marked one example of each species. Can you tell the rest apart? So we run pilot studies. If you've never heard the term, "pilot study" refers to a small, easy, preliminary study that a scientist undertakes in order to collect preliminary data, prove that their idea will work, and leverage those positive results into something bigger. You try things out in a small way before going for the big win. If you run a pilot study, things usually work out better for the real study. One of my limpets with its egg mass, phot

Tears

"She usually cried at least once a day, not because she was sad but because the world was so beautiful and life was so short." - sign in a coffee shop I am sitting on the couch, dressed in sweatpants and an old shirt. Sun streams into the living room from windows on three sides, and the storm door creaks open in the wind. To my right, a pile of clean laundry waits to be folded. At my feet is a plastic tarp strewn with dive gear, spread out and waiting to dry. Carl and I joke that our decorating style should be named "We lead full lives," and the mess in the living room today supports that theme. We had an incredible dive today, and I am as happy as I've ever been. We left the house a few minutes before 5 am and headed up to Beverly, a small town on the North Shore. After loading our gear onto a 30' boat, we steamed out to a mooring about a half mile off the Massachusetts coast. We had reached the wreck of the Chester Poling . The Poling was my first N

Cherry calamari

It was dark, and the water was full of silt. I could only see my light and the tips of Joe's bright red fins in front of me. The temperature was a chilly 57 F, but only small parts of my face were exposed to the water. The rest of my body was isolated by my drysuit, protected from the dark, cold ocean by neoprene and latex. Ahead of me, Joe stopped swimming and trained his light on something beside him. I pulled up short and pointed my light toward the spot. Behind me, Giorgio did the same. "Must be fish," I thought, recalling Joe's affinity for charismatic megafauna. The three of us held still in the water column for a while, illuminating the slim, purple creatures with our dive lights, surveying them visually while trying not to disturb them otherwise. After a long minute, Joe started swimming forward again, using his light to illuminate the guide line strung across the seafloor. I followed suit, but after just two fin kicks, I had moved forward far enough to get