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Gulf of California 2015, Leg 3 – Biodiversity and Biooptics – Log 3

Gulf of California 2015, Leg 3 – Biodiversity and Biooptics – Log 3

Larvaceans, Jellies, and other Animals

George Matsumoto writes: My primary research interests are split between larvaceans and jellies. On the basis of MBARI’s 2003 Gulf of California expedition where we found thick layers of giant larvaceans at a depth of 15 meters, I have been hoping to investigate the fluid flow patterns within the inner filters of these animals. Our visit to the Gulf in 2012 found the same dense layers of giant larvaceans, but at 35 meters—a little too deep for our SCUBA diving efforts. Thus far in 2015, the larvaceans have been remarkably sparse and the few that we have seen with the remotely operated vehicles have been around 80-110 meters. Again, too deep for SCUBA, but I am hopeful that we might find some shallower ones as we move farther south.

Surprisingly, we have not yet seen the thick layer of giant larvaceans (Bathochordaeus) that I am looking for, but we have observed several of these smaller fritillarid larvaceans in deeper waters. They build very intricate mucus houses to filter detritus out of the water column for food. The red box outlines the animal.
The map shows a site we visited during the GOC 2012 expedition, and are revisiting this year.

Luckily, one usually keeps a backup research plan. My backup plan focuses on jellies. We have found some beautiful and interesting jellies here in the Gulf that do not quite fit in any of the known species. Over the next few months I hope to work up these unusual jellies, which involves a thorough literature search, morphological observations, and molecular analyses. Coming out here with Steve Haddock is an educational experience as he has spent much more time at sea than I have and knows so much about the jellies we are seeing. Steve and I first met over 20 years ago when the Monterey Bay Aquarium and MBARI hosted the first (and only) Jellyfest in the aquarium auditorium. It was a remarkable meeting of researchers with similar interests and helped to start the Monterey Bay Aquarium’s world-renowned jelly research and exhibits.

Several interesting jellies I’ve been observing during the ROV dives.


MBARI is a wonderful organization and I am lucky to have been employed here for almost 19 years. For me, a big challenge is trying to ensure that I make time for my science. I have a great deal of flexibility with my work schedule, but I also have a lot of education and outreach responsibilities, so my research seems to take a lower priority. I will continue to work on that, so that I can devote more attention to science. The most difficult part about being at sea is being away from family. As much as I love engaging in cutting-edge exploration and research in the field, I miss being home.

—George Matsumoto

Kyra Schlining writes: Some highlights from today’s dive include:

We spotted this large cranchiid squid, Galiteuthis pacifica, as it was feasting upon another large squid (perhaps Leachia danae).

Although both are exquisite, the juvenile form (top) of this purple lobate looks very different from the mature lobate ctenophore (bottom). We are able to reveal these relationships using molecular analyses.