Friday, July 12, 2019

The Portland: part 3

My shipwreck project has a strong media component in addition to the science. In September, we will be back at the Portland wreck site and broadcast live from the ship using telepresence. The broadcasts will allow schools, museums, and the general public to join in the expedition and study the Portland for themselves.

This week, we did one broadcast from the dock in Gloucester, which was live on the NOAA Office of National Marine Sanctuaries' Facebook page. I apologize for not posting the link here in time for readers to join in, but the video was recorded and can be found at this link or embedded below.

I also highly encourage you, friends, to follow the NOAA Office of National Marine Sanctuaries Facebook page (find it here) because that is where telepresence broadcasts for the general public will appear in September. We'll be at sea September 16 - 19 with telepresence, so stay tuned!

The Portland: part 2

Friends, I am back out at sea on the Dawn Treader to study shipwrecks in Stellwagen Bank National Marine Sanctuary! My team set aside this week for ROV dives on the wreck of the steamship Portland, sunk in 1898. It took us a while to figure out the best way to work in our study area, but we eventually smoothed out all the kinks and collected 8 hours of good footage. It was so rewarding to see the wreck!

ROV Pixel on board the Dawn Treader
Working in Stellwagen Bank National Marine Sanctuary is actually pretty challenging. At 450 ft (137 m) deep and ~30 nautical miles from shore, the Portland is in a weird middle ground. It's too deep for SCUBA diving but not far enough offshore to justify the use of a large regional- or ocean-class research vessel. It's not a shallow coastal habitat, but it's also not quite deep-sea either. We're filling in the gap with day-trips on a small (30 ft/9 m) boat and a small ROV, but we've had to contend with some logistical difficulties. The boat does not have a dynamic positioning system like the larger ships, so we came up with a dual-anchor system to keep it in place over the wreck. The ROV is light enough to be carried away by the strong tidal current, so we added weights in various places. It took a while for us to figure everything out, but my team has finally hit a rhythm. We are working more and more efficiently, and we reaped the benefits of beautiful footage from the shipwreck.

I was very excited to see what organisms were living on the Portland, and the wreck did not disappoint! Large plumose anemones covered the hull near the stern, and fat orange cushion stars spotted the wreck. I wasn't surprised to see plumose anemones - they have been on every wreck in the North Atlantic that I've been able to lay eyes on. I think they have a unique life-history that allows them to be successful on island-like habitats. The cushion stars were also no surprise. I spotted some individuals on the mud surrounding the wreck, so they may have migrated from the surrounding area.
Some members of the field team. Left to right: Evan Kovacs
(Operations lead, videography), Mike Skowronski (ROV
pilot), Calvin Mires (archaeology), and me (biology). Photo
by David Ullman (captain).

What surprised me were the sponges. Large, bulbous yellow sponges were common on the hull, and a second spherical species was common too. There were even bowl-shaped white sponges similar to ones I've seen in the Arctic! I had never seen so many large sponges on a shipwreck before. Sponges are generally considered to have restricted dispersal (the larvae don't go far from their parents), so they would not be expected to reach an isolated, island-like shipwreck. I will have to figure out where the sponges came from and how they reached the wreck!

Friday, June 28, 2019

The Portland

It was a grey, foggy morning in Gloucester, Massachusetts. We pulled away from the dock at 5 am. Steaming offshore aboard the Dawn Treader, I had a sense of eager anticipation. The boat started rocking as we exited the harbor, and the engines' hum turned to a roar. Enveloped by the sky and the sea, water in its various states and shades of dull gray, we steamed forth until there was no land in sight.

All quiet in Gloucester Harbor
After two hours, the vessel slowed, and the Treader sloshed back and forth in her own wake. Two men scrambled to the front of the boat and waited for the captain's command to drop anchor. I watched eagerly over his shoulder as we approached our study site. The echosounder showed only a clear water column - nothing between us and the mud 450 ft below. We drifted. Moments passed quietly as the boat rocked in the fog. Just then, pixel by pixel, a bump appeared on the screen. The seafloor seemed to rise up beneath us and then fall back down. It wasn't big, but it was something.

"Drop!" called the captain, and the anchor's chain rattled over the edge of the bow.

We had reached the wreck of the Portland.

Friends, this summer, I am working on my first federally-funded project as a WHOI scientist. I'm collaborating with an archaeologist, an underwater videographer, and several staff members from NOAA's Office of National Marine Sanctuaries to examine shipwrecks in Stellwagen Bank National Marine Sanctuary, offshore of Massachusetts. Most of our field sampling is taking place this summer, and then in September, we'll continue our work during live telepresence broadcasts. Yes, that means anyone with an internet connection can follow along as we explore the shipwrecks, and yes, I will post links and a broadcast schedule as the time draws nearer!

Dawn Treader in Gloucester Harbor. The red thing on the back
deck is Pixel (I'll get better photos soon), and the green spool
is Pixel's tether.
Our team is using a state-of-the-art, cinema-class remotely operated vehicle (ROV) named Pixel to record high-resolution videos of the shipwrecks. We'll use the videos to analyze the state of each shipwreck, how the wreck site has changed over the last 10 years (my archaeologist collaborator uses the term "site formation processes"), and what's living on the wrecks compared to nearby boulder reefs (that's my job!). We're also planning to build 3D models of some shipwrecks that can be used as educational and outreach tools. It's very exciting work!

Our first wreck is called the Portland. It's a steamship that ferried passengers from Portland, Maine, into Boston, and the ship sank with all hands during a famous blizzard called the "Portland Gale" in 1898. Our investigation marks the first time the Portland wreck has been visited in 10 years and the first complete documentation of the wreck site.

Right now, we're still figuring out some logistics, but I will have much more to share about the project over the next few weeks. Stay tuned for updates from the Portland!

The metamorphosis

"Als Gregor Samsa eines Morgens aus unruhigen Träumen erwachte, fand er sich in seinem Bett zu einem ungeheueren Ungeziefer verwandelt"

"As Gregor Samsa awoke one morning from anxious dreams, he found himself metamorphosed in his bed into a monstrous insect."

- Franz Kafka in The Metamorphosis, translation mine
A Crepidula fornicata larva before metamorphosis

Friends, I am back in Woods Hole and once again working on my experiment with Crepidula fornicata. I collected mothers from the field and kept them in different temperature and feeding conditions while they were brooding their larvae. Now that the larvae have hatched, I'm collecting data to see if there are any carryover effects. As I've already mentioned, I'm measuring the sizes of the larvae as they grow. I am also seeing how long it takes the larvae to develop to metamorphosis. 
A Crepidula juvenile after metamorphosis, laying on its
back so the foot is exposed

Everyone is familiar with at least one example of metamorphosis, which is a caterpillar becoming a butterfly (or a human becoming an insect, if you're into early 20th century Existentialist literature). You may or may not be aware that marine larvae do the same thing. In most cases, the larva looks nothing like the adult form, so larvae go through a transformation when they settle. Their tissues are rearranged; some structures are re-absorbed; others are constructed for the first time; and the animal looks totally different when it's done. In one extreme case called "catastrophic metamorphosis," ribbon worm juveniles develop inside the larval body and then eat their way out of the larval body when it's time for metamorphosis. (I'm not kidding; watch a video of the process here.)
A juvenile Crepidula crawling in a petri dish. (If you can't
tell, I got a new microscope with a built-in camera!)

For Crepidula, metamorphosis isn't too extreme. The larval swimming organ, the velum, disappears, and the muscular foot grows larger. The cilia that once kept the larva suspended in the water column are shed. The spiral-shaped larval shell grows a new brim so the juvenile can sit flat on a surface. That's it. What's really nice, though, is that metamorphosis can be reliably triggered by exposure to potassium chloride. Stick a Crepidula larva in 20 mM KCl, and if it is ready to metamorphose, it will. This means KCl exposure can be used to assess whether a larva is competent (ready to metamorphose) or not. 

So every few days, I'm taking a sub-sample of larvae and exposing them to KCl. I leave them overnight, and then I come back and count how many have metamorphosed. So far, it looks like there might be some differences between larvae from different mothers. I'm excited to have data!

Thursday, May 30, 2019

Costa Nova

Costa Nova beach

The workshop ended in mid-afternoon on the third day, so I had a chance to explore more around Aveiro. When I mentioned to another researcher that I was thinking of walking to the beach, he shook his head. I would have to walk along the highway, he said, but he was going to work in a café out there and would be happy to drive me. We grabbed one more researcher who was interested, hopped in the car, and headed to Costa Nova.

Barra lighthouse in Costa Nova
Driving out of Aveiro on the highway, we passed the Ria Aveiro estuary and large salt flats. Aveiro is on the coast, but the space between the town and the beach itself is filled with pools where seawater is evaporated to harvest salt – one of the major industries in Aveiro in historical and modern times. There has been trade between Portugal and Norway since about the 12th century, with the Portuguese exporting salt and importing salted codfish.

Striped homes in Costa Nova
The beach reminded me a lot of Oregon. There were steep sand dunes and large waves. Stone jetties extended out into the water and served as habitat to algae and mussels at their deeper ends. Familiar shells covered the beach – blue mussels, cockles, clams. Some fishermen fished with large poles from the jetties, and there was a tall, red-and-white-striped lighthouse. It was gorgeous.

What surprised me was the town. Costa Nova, located just outside Aveiro, is a vacation destination, and it looks the part. Pale adobe houses with terra cotta roofs lined the streets, but many of the houses have a more maritime look. They were painted with vertical stripes, always in a bright color that alternated with white. The Portuguese researcher explained that in the old days, homes in Costa Nova were
Ovos moles
built from long wooden boards placed vertically to form the walls, and the boards would be painted in alternating colors. For whatever reason, the aesthetic has remained popular even though wood is no longer used. The overall effect was of a storybook town on the water, and despite the short distance between them, Costa Nova felt very different from Aveiro.

The last thing I did in Portugal was try a local delicacy called "ovos moles." In Portugal, it is traditional to make sweet treats with a custard of egg yolk, cream, and sugar. Nuns traditionally were master bakers in Portugal. They needed the egg whites for other household tasks, so they had numerous egg yolks left over and developed delicious ways to bake them. Ovos moles consists of a thick, baked egg-and-cream custard surrounded by a wafer similar to a communion wafer (making it even more obvious that the treats were invented by nuns). I tried some from a bakery in downtown Aveiro that came highly recommended, and they were good! Not too sweet, very thick with a mild egg-yolk flavor.

I have greatly enjoyed the chance to experience Portugal this week. It has been a good workshop!

The workshop

I really enjoy scientific workshops. Unlike conferences or seminars, where we just talk about our research, workshops have a defined goal and a short amount of time in which to achieve that goal. The discussions have more direction, and we make measurable progress by the end. It feels very productive.

The objective of this workshop was to collect and synthesize ideas for long-term collections of larvae in the deep sea, for example through an observatory. We met at the University of Aveiro for three days, and by the end of the second day, we had our ideas pretty well together. We had presentations from participants and open discussions, which eventually resulted in some solid, tractable directions and even an outline for a paper. Each of us left Aveiro with an assigned section to write. It will be very exciting to watch the draft come together!

The workshop reminded me how fortunate I am to hold a solid place in the marine biology community. I am affiliated with some truly world-leading experts, and by virtue of my training, experience, and current position, I am included in their circles. The workshop actually reminded me of how much knowledge I possess, because I was one of the researchers in the room with the most experience collecting deep-sea larvae. It was satisfying to be able to contribute to the discussion.

It has been a productive time in Aveiro!
Workshop participants on the University of Aveiro campus

Aveiro in photos

Streets in Aveiro tend to have very long names describing historical events.




This bridge was covered in ribbons with text on them

Ceramic factory

Barcos moliceiros - essentially Portuguese gondolas