June 14th, 2021
The days are beginning to feel similar at these sights. Again, we started the day with a short dive with Jason down to the seafloor. On this dive we completed the video transects of the brine pool sight and recovered Lauren’s trees and trampolines. We also deployed the Technicap carousel, a collector that opens a new tube every month to collect larvae.
In the early morning we also had a Sentry recovery, right before Jason went in the water. After sorting for morphotypes over the past three weeks, we’ve gotten fairly good at identifying different larval types in our samples. We can correctly identify gastropods (snails) over pteropods, and bivalves over ostracods. While these imposters are still all over the samples, we were getting fed up with another organism; the nauplius. Nauplii are the larval form of copepods (or barnacles), the crustaceans that make up the majority of individuals in our samples. These tick-looking larvae are not ones we are looking for, but we have been finding them all over the SyPRID samples. To cope with this, we came up with a little nursery rhyme:
“Fatty fatty nauplii
Swimming in a row
Clogging up the SyPRID Sample
From the plankton tow”
Later in the day, the scientists got to work sorting through the sieved water and sediment from the bioboxes on the Jason dive yesterday. While the samples were dense with black, oily, sediment, we had a welcomed surprise. Usually whenever we find a pink Bathymodiolus shell, the team is ecstatic, and the finder calls it out with glee. That’s how sorting these samples began. Each of us would take a sample from our container, immediately find one of these pink treasures, and shout it out. Then we began seeing a few more, until looking more closely. We were finding Bathymodiolus shells everywhere! Using these larval shells for isotope analysis requires a good amount, but we had found over 100 within 30 minutes! What takes us hours on other sites, we had completed in record time here. This makes our job easier and can put a higher priority in searching for live larvae for pictures, videos, and preservation.
Once Jason was back on board, we left Brine Pool and moved to the last site in our trifecta: Bush Hill. The site is faithfully named for being a large hill with tubeworm bushes on it. When we arrived, Sentry was expertly deployed yet again, to get the first of our two SyPRID samples at each site.
We ended the day with a beautiful sunset outside. Many of us have been working so hard that some of us have only seen a few, or no sunsets from the entire cruise! The different sleeps schedules also play a role here, with some people typically sleeping while the sun goes to bed itself. While the sun was setting, we were told about a legend at sea called the Green Flash. Apparently, when the sun hits the horizon on open ocean, there is a flash of green visible to those who watch. We all watched closely, hoping to observe this phenomenon, hardly blinking as the horizon met with the sun. But the green light didn’t appear, not at the horizon, nor at the end of the dock. Regardless, it was a beautiful sunset.