Wednesday, May 31, 2017

On the rocks

It started a few weeks ago. I was sitting around my kitchen table with friends, sipping wine and chatting after dinner.

Wood Neck Beach
"Hey Kirstin," my friend and fellow postdoc, Cassidy, called from across the table, "Can you recommend a good field guide for the New England intertidal? I need to get familiar with the local organisms this summer."

To my left, my boyfriend almost snorted. "Cassidy," he informed her, "Kirstin is a field guide to the intertidal. Just take her with you!"

So she did.

Yesterday after work, Cassidy and I headed out to Wood Neck Beach, just north of Woods Hole. Unlike most beaches on the Cape, Wood Neck is covered in rocks of all sizes - gravel, cobbles, boulders. We went at low tide so we could see the organisms when they were exposed.

Semibalanus and Littorina on a rock on Wood Neck Beach 
The main organism we saw was the northern rock barnacle, Semibalanus balanoides. Barnacles are especially common in the high intertidal because they are outcompeted by other organisms at lower tidal levels. They are also well-adapted to survive in the high intertidal, an area exposed to air for long periods each day. Their shells can shut tightly, sealing water inside and helping the barnacle avoid dessication. Semibalanus was all over the rocks on the beach. We also saw a number of black snails, Littorina littorea, known as the common periwinkle. Littorina is a common herbivore with a smooth spiral shell.

A boulder with barnacles, oysters, and mussels
On some of the larger boulders, we could see eastern oyster shells (Crassostrea virginica) and blue mussels (Mytilus edulis). Whenever we did find blue mussels, they were on the underside of a large boulder. Mussels prefer to be lower down in the intertidal zone so they don't dry out. They're also pretty good competitors, so they can hold their ground in preferable habitats. If you look on the boulder here at right, you'll see Semibalanus all over the face of the boulder. The two large white spots are Crassostrea oysters, and then on the bottom, you see dark lumps. Those are Mytilus, blue mussels.

I absolutely love tide-pooling, and if you've been following this blog for a while, you have read about my intertidal excursions in Oregon before. Tidepooling became almost a hobby for me. I haven't gone nearly as often since moving east, though, because intertidal communities in New England are much less diverse than on the west coast. Still, it was great to get outside with a friend and explore some of the local biodiversity!

Cassidy and I on Wood Neck Beach

Friday, May 19, 2017

Mystery blob

A Mystery Blob, photographed at 50x magnification.
I checked my dock study in Eel Pond yesterday, right on schedule. When I put the first fouling panel under the microscope, I was happy to see many of the same organisms I have come to recognize: spirorbids, hydroids, and a barnacle or two. I was chugging along, counting organisms, until something orange caught my eye. It looked like it was encased in a ball of mucus, so it might have been nothing. I increased the magnification on the microscope just to make sure.

What I saw was definitely not nothing, though what it is, I cannot say for sure. I'm calling it the Mystery Blob.

Once I saw the first Blob, a strange thing happened. I used the microscope to zoom back out, decreasing the magnification so I could see more of my panel, and when I did, my eyes started seeing Mystery Blobs everywhere! Once I had a search image for them, my brain was able to detect other Blobs on the fouling panels. They were actually pretty abundant.

So what is a Mystery Blob? I still can't say for sure, but my gut says it's an ascidian, also known as a sea squirt. Ascidians are tiny invertebrate animals that live in colonies and filter the water for food. They have the same squishy texture as my Mystery Blob, and I think the faint orange ring on the left side of the blob in the photo is a siphon, something all sea squirts have. If I'm right, then over the coming weeks, each Mystery Blob should grow into a colony, cloning itself over and over and spreading across the plate. Larger colonies will be much easier to identify than single, newly-recruited individuals. Hopefully, I can identify the Blobs to species soon!

Tuesday, May 16, 2017

Chainsaw carving: part 2

Crassostrea virginica larvae, photographed using a dissecting
microscope at 10x magnification. Photo by Erin Houlihan.
There's something very satisfying about finishing a manuscript. As you know, I've been analyzing data on oyster larvae behavior, whittling the results down to reveal a meaningful story. As of today, I am finally finished! I drafted two complete manuscripts, both about settlement behavior of the eastern oyster, Crassostrea virginica. One focuses on larval behavior at different ages, while the other is about how oysters settle in low pH conditions brought about by ocean acidification.

With the first complete draft of the manuscripts finished, it's my co-authors' turn to sculpt. Four other people are involved in the oyster studies - scientists who designed the studies, ran the experiments, and collected the data. The project has really been a team effort - I was just the one designated to write up all of the results. It's been fun, though. I've gotten to know a phenomenal undergraduate and another postdoc in the process. Often, the best part about science is the people I get to work with.

It feels like I've been climbing a hill and finally reached a crest at the top. To stick with my chainsaw metaphor, though, I should tell you I've finally turned off my beastly, gas-powered tool and let it fall from my hands into the sawdust. Taking a breath of sweet-smelling air, I step back, rip off my dusty gloves, and gaze at my creations. I push a sweaty lock of hair from my face. "That'll do," I whisper to myself, "that'll do."


Wednesday, May 10, 2017

Hydroid explosion!

A large colony of Obelia geniculata on one of my
fouling panels in the lab
"I might only have one match
But I can make an explosion"
- "Fight song" by Rachel Platten

Kneeling on the dock, I undid one rope, then another. I pulled up on the white thread, grabbed the edge of the PVC, and flipped my experiment up onto the dock.

And gasped in awe.

My panels were covered in hyrdoids. Big, stringy, wet colonies of Obelia. Pink buds of Tubularia all over my plates. It was a hydroid explosion!

I should have known it was coming. I mean, the hydroid colonies on my monitoring plates exploded after a few weeks. Just a few individuals can grow into a massive colony. I had thought it was already too late in the spring for hydroids to dominate the community. Guess not.

Discovering the hydroids on my experiment yesterday is an example of one of my favorite parts of ecology: the element of surprise. When I first formulated the hypotheses for my succession study, I didn't even think hydroids played a big role. I thought they might show up in small numbers with the first wave of barnacles, but that they would quickly be outcompeted by other organisms. This prediction was based on my experience with fouling panel studies in both Oregon and the Arctic. But I was wrong.

A colony of Obelia geniculata, photographed using
a dissecting microscope at 50x magnification
I actually had to adjust my experiment a little, because I hadn't been planning to consider the hydroids' role in succession. I selected a random sub-set of panels and designated them "RH" for "remove hydroids." From now on, whenever I curate my dock experiment at the WHOI pier, I'll remove all the hydroids from that sub-set of panels and see if the communities develop any differently.

I'm excited to include the hydroids as an important group in my study now. Hydroids increase habitat complexity (by forming their big, stringy colonies), so I'm curious if they have any effect on other organisms settling on the panels. I shall see! More surprises await!

Friday, May 5, 2017

Noticing beauty: part 2


Woods Hole, MA
Falmouth, MA

Sunset from the WHOI pier

Moon over Falmouth Heights

Swan in Vineyard Sound

Vineyard Sound color palette

More interesting: part 2

"There is no such thing as bad weather, only bad clothing." - German proverb

I was covered head-to-toe in waterproof fabrics. I wore my rain jacket, rain pants, and even my thick, hard-core field boots. Wheeling my formidable fat-tire bike out the door of the research building, I greeted the rain. It was now or never - if I wanted to go home, that is.

It's supposed to rain 2 inches (5 cm) all over Cape Cod tonight. Strong winds, coastal flooding - we're getting hammered. On my bike ride home, I had to cinch my hood around my face to reduce drag and lean my bike into the cross-shore wind to keep from tipping over. The waves on Trunk River Beach were the highest I've ever seen. My waterproof clothing shield was quickly covered in puddle splashes and salt spray, but I pressed on. Biking level: Expert. (For the record, the levels are Novice, Beginner, Intermediate, Advanced, Expert, Legendary, and Dutch.)
A spirorbid polychaete (tube worm) on my fouling panels.
Even though it's magnified 50x, it's still small in this
photo, demonstrating just how tiny these organisms are.
Scroll down to part 1 of this post and check out the barnacle
photo - both were taken at the same magnification, so you
can see just how great the size difference is! 

Considering the logistical difficulities today's storm brought, I was very glad to have curated my dock study yesterday. Every time I check the fouling panels, my study gets more and more interesting, and this week was no exception. I retrieved panels from Eel Pond and discovered ciliates, barnacles, and two new organisms - a spirorbid polychaete (tube worm), and a bryozoan.

If you've been following this blog for a while, you'll remember I talked about spirorbid polychaetes when I was studying recruitment in the Arctic. They live inside little calcium carbonate tubes and filter the water to feed. The species on my fouling panels now is actually one of the same species I found in the Arctic. Its distribution extends throughout the north Atlantic and even up to Svalbard - pretty cool, right?

The coolest thing about my dock study is that so far, the data I've collected fit my hypotheses perfectly. I expected the first organisms recruiting to my plates to be all hard-shelled, calcareous species - and that's exactly what I've found. I have a whole other set of hypotheses about how the communities will develop if I remove those calcareous organisms or leave them be, and I won't be able to tell if those predictions are true for another couple months. I'll keep collecting data every week and update you as I learn more. For now, I'm staying inside and out of the rain!

Tuesday, May 2, 2017

At the library

It was dark on Water Street as I stepped out of the library. I waved goodbye to J and headed down the sidewalk. Across the street, small white lights glowed around the sign for Pie in the Sky, our local bakery.

"Kirstin!" I heard someone call to my right. My friend, Kristina, stepped towards me, hands in her red jacket pockets. I thought she had already gone home but was glad to see she was still there.

"Do you want to go for a tea?" she asked, nodding toward Pie in the Sky. Of course I did!

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Sitting in a folding chair, I leaned over to arrange a few items in my backpack. The lower floor of the library was probably as full as it had ever been, with seminar attendees milling about and chatting. I was proud of the job I had done. Out of the corner of my eye, I could see someone in a flannel shirt and jeans approaching me. I looked up.

"I have a question, if you don't mind," he began. "Can you define 'benthic'? Because I always thought it meant things that were deep, but your research is right off the docks."

I explained that "benthic" referred to any organisms that lived on a surface, no matter what their depth. It was a good question, and I chatted with the man for a few more minutes.

- - - - - - - - - - - - - -

I stood up at the front of the room, laser pointer in hand. Someone dimmed the lights. My title slide formed a white square on the projector screen. Orange stripe at the bottom for color. Text in blue for contrast. I called it "Fauna most foul: discovering how and why dock fouling communities change over time." I thought my title was pretty clever.

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Backpack on my shoulder, I walked into the seminar room. Folding chairs were set up in rows with a projector in the middle. Only one other person was there, typing on her laptop in the front row. I slowly approached.

"Hello, are you in charge?" I asked.

She looked up at me with thick glasses and a smile. "Nope! I'm the other speaker. Nice to meet you." We shook hands.

She was more than enthusiastic about her research, talking at lightning speed about plate tectonics. She made seismology sound like a trip to the candy store. She was a beginning Ph.D. student and actually reminded me of myself a few years ago.

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I love sharing my research with others, so when an opportunity opened up to speak at the Woods Hole Public Library, I took advantage of it. The population of Woods Hole, Massachusetts has a much higher proportion of scientists than your standard small town, so I was glad for the chance to practice communicating my science to an educated, albeit non-specialist, audience. I also got to connect with new acquaintances and spend time with a good friend. It was a great evening.