Amanda Netburn is a PhD student at the Scripps Institution of Oceanography. Her research focuses on the role of deep hypoxic waters in structuring midwater fish communities off the coast of California. On the San Diego Coastal Expedition, she will be studying animals that live in the open ocean, while other student researchers investigate the role of oxygen and methane seeps in structuring marine communities on the seafloor.
The author, Amanda Netburn, buried in sea urchins.
Whew, I can’t believe we’ve only been out here for two days! The Shelf and Midwater teams have combined to form the “Zonation Zombies”. Zonation, because we all study the way that animals form layers in the ocean based on depth and environmental variables such as oxygen and temperature. Zombies, because, well, we work a lot in the middle of the night! The Zonation Zombies have been very busy- we have attempted 4 bottom trawls and one ROV (Remotely Operated Vehicle) dive.
My shipmate, Kirk Sato, is collecting sea urchins for a project to study how they build their tests (aka “shells”) under ocean acidification conditions. The predicted decline in ocean pH is expected to affect the ability of calcifying animals, like sea urchins, to build and keep their shells. Well, he certainly isn’t having trouble finding specimens (see pictures)! I was knee-deep in these crunchy spiky creatures from the seafloor, and it took three hours to sort just one haul!
The two types of urchins. On the left is the “irregular” urchin, or “heart urchin.” The “regular” species is on the right.
Three of four tows went off without a hitch, but our catch was so heavy on a forth it fell back in while we pulled it out of the ocean. We were extremely bummed to watch this valuable data wash back into the sea. It’s an unfortunate but inevitable part of fieldwork that things sometimes just don’t go as planned. Hopefully we will find some time later in the research cruise to return to the site and repeat the trawl.
Some other cool things that we found in the bottom trawl include: octopi (one pictured left), a snailfish (pictured below), lots of flatfish of various species (see my first post for a picture), mud owl worms (pictured), and starfish. We had a lot of fun identifying and sorting the animals. The animals have now been preserved for several different studies that will be carried out back on land. We have a few more bottom trawls on the schedule before the trip is over, and look forward to collecting more awesome animals.
Snailfish collected with otter trawl.
Both yesterday and today, we deployed a Remotely Operated Vehicle (ROV, see here for a description of our science goals using the ROV) to look at these animals on the seafloor. We get a lot of information from seeing the animals in their natural habitat, like how they are distributed- Do they clump together? Do they spread out?, and how they interact with each other- things we can’t learn from nets alone. Imagine looking at animals in a tidepool compared with taking them all out and observing them in a bucket.
The ROV dives each broke records for longest dive of the new Scripps’s ROV. Yay!
Sternaspidae (Polychaete) worm. Common name: mud owl.
Next up is midwater work. I will be collecting animals that live in the open ocean, a community of odd deep-sea fishes, jellies, and shrimplike animals. I look forward to telling you more about what I’m working on out here.
For background on the San Diego Coastal Expedition, please visit:https://sites.google.com/site/sandiegoseaflex/
Scientists at work in the ROV Control Room.
Photo of the live feed in the ROV Control Room.
Previously in this series:
The San Diego Coastal Expedition
The San Diego Coastal Expedition: Underway!