Mars

"I would like to die on Mars. Just not on impact."
- Elon Musk

I love fall in New England. The air is crisp, the leaves are crunchy, and the sunshine feels comforting instead of hot.

I’m back at home now, and I used the chance to finish up my field project from this summer. Weather prevented me from making out to my third field site, the wreck of a fishing vessel called the Patriot, to recover my samplers earlier in August and September, so I scheduled a day on the dive boat Dawn Treader to try again. Unfortunately, the weather prevented me from reaching the Patriot all over again, but I was able to use the day to explore a new site closer to shore.

We went to the wreck of the Mars in Cape Cod Bay. I had never been to this site before, and I wanted to see the wreck for myself. At first, it would seem that there’s plenty of information available about wrecks in Massachusetts, but a closer look reveals that this pre-existing information is biologically sparse. It’s easy for me to find out what year a ship was built, how many hands were on board, why it sank, and how intact it is, but other divers and shipwreck enthusiasts utterly ignore the animals living on the wreck. To find out what’s there, I have to visit the wreck myself. I packed my gear, picked up my dive buddy for the day, and went to the site of the wreck.

To be honest, the Mars was a really tough dive for me. The cold water shocked my system, which had acclimated to tropical temperatures while in Palau. It was dark and turbid, so visibility was restricted to the 5 feet in front of me. I was also disoriented by nitrogen narcosis, which is a cognitive fogginess that results from breathing the gas at high partial pressure. My brain was functioning more slowly than normal, and even though I knew I was off, I had no way to fix the problem at depth.

Metridium senile on the Patriot wreck. Photo by Jim Guertin.

We swam around a little and eventually found the wreck. The bow was still intact, standing vertically above the seafloor, and as I ascended up the metallic wall, my head began to clear – just a small change in depth made a huge difference for my narcosis. All over the bow were hundreds of plumose anemones, known scientifically as Metridium senile. There’s a picture of one here, which was taken by another diver on a different wreck. The species is really gorgeous, and it has been on every shipwreck in New England that I have visited so far. I think the anemone may be pre-adapted to thrive on shipwrecks because it can disperse long distances and form populations from just a few individuals.

Even though it was a tough dive on the Mars, this project has taught me several important lessons. I’ve gained valuable experience with deep offshore diving in cold water – a difficult set of conditions that requires regular practice to master. I’ve learned the ins and outs of WHOI regulations for diving and boat charters. I have made key observations of species distributions on shipwrecks and started formulating hypotheses to pursue in future projects. Overall, it’s been a valuable learning experience, but I am glad to finally call my field season finished. Autumn is rolling in.