Ever wonder how a research museum acquires new specimens, what researchers do on an oceanography cruise, or what personal challenges cruises create? This post is the second in a series that provides a behind-the-scenes look at how researchers prepare for a cruise, working life on the boat, and how specimens are recovered and introduced into the National Museum of Natural History (NMNH)’s research collections.
Editor’s note: This piece is a special communication from Invertebrate Zoology (IZ) research zoologist Karen Osborn, who is at sea on the R/V Western Flyer, a research vessel owned and operated by the Monterey Bay Aquarium Research Institute (MBARI). Amid the team’s grueling day-and-night research efforts, which include transect sampling within the water column, collecting animal respiration data with a new midwater respiration chamber, and recovering new specimens, Karen has found the time to relate her story to you. Please stay tuned for the third piece in our series, which will highlight the work of museum technician Kristen Mercer and kick off an exciting new series on collections management practices. Enjoy!
Direct from the R/V Western Flyer to you
What to tell you about first – I can’t decide! It has been a great cruise so far with lots of wonderful animals spotted and collected. It has also been nearly two years since I have been able to join the Robison team, which means I began this cruise with a long list of things I wanted to find and examine. I work on pelagic invertebrates, which tend to be extremely delicate and change dramatically once they die, so seeing them alive and having the chance to observe and document these animals in an undamaged form within their natural habitat is crucial to understanding their biology.
In my own research, I study hyperiid amphipods with my postdoc, Jamie Baldwin-Fergus. So far, I’ve been able to collect six specimens with the remotely operated vehicle (ROV) Doc Ricketts. These hyperiid amphipods belong to the superfamily Lanceoloidea, which includes deep-living, free-swimming amphipods. We are particularly interested in these organisms because, within this group, we find a wide range of eye forms, from none at all to large, complex, compound eyes. In particular, the Scypholanceola possess strange, orange, mirrored eyes that are split into two parts by tall ridges of exoskeleton. These ridges limit the direction from which light can strike the eye. We want to know how Scypholanceola process the information gathered by the different regions of the eye to see how far this eye structure has come toward splitting into two separate eyes, which is a characteristic of several other hyperiids.
The squishy side of ocean life
I’ve also been working on a fascinating group of polychaete worms that can be found in abundance throughout the entire water column. These worms are transparent, although they sometimes exhibit dark red or purple guts and can have red or orange tinged bodies. They are agile, active swimmers that spew yellow light from their arm tips and can grow to more than a foot in length. I’ve been trying to sort out the different species that are present off the coast of California, in addition to generating characters that will allow us to identify live specimens. The latter interest of particular significance: most characters used for identification in the literature require removing the parapodia, which kills the worm.
I am also looking at their distribution, reproductive biology, visual ecology, and the genetic structure of their populations. When we spot a polychaete, we capture a bit of high-definition video of the worm before trying to capture it in one of our samplers, which allows us to safely bring the animal to the surface. As long as polychaetes aren’t injured during collection (e.g., by being scraped down the side of a trawl net), they are surprisingly sturdy animals and will swim vigorously for hours after collection, even when immersed in full-strength sedative (magnesium chloride mixed to be the same osmolarity as seawater).
Typically, I take several photos of a specimen as soon as I bring it aboard to document what it looks like. For polychaetes, I focus on the shape and placement of the nose (nuchal organs), which we can’t see from the ROV. Then, once fully anesthetized, I take tissue samples for genetic work and fix the rest of the animal for morphological work back at the museum. On one particularly large specimen, I was able to capture a close-up image of the worm’s kidneys (nephridia) with a level of detail that I’ve never been able to see before, which was really exciting!
An oceanographer’s life at sea
Days are busy on board. The ROV launches at 6:30 a.m. and is in the water until 6:30 p.m. Two pilots and two scientists are needed to run the ROV, but often there are several additional scientists in the control room searching for the animals they want or helping out in other ways with the data and video streams. We’re always looking for multiple things at once, because in such a huge, dynamic habitat like the midwater, you never know what you will—or won’t—find. Then, the ROV comes up, and we offload all of the animals that we’ve collected and transfer them to tanks in a cold, dark room where they await their scientific fate.
Meanwhile, the team launches the midwater trawl net, which will be raised at about 11 p.m. While the tow is underway, we work up the animals from the ROV. Then, we haul the net and its catch aboard, sort the contents, and work up the new animals. It’s always exciting to see what we’ve caught in the trawl: there can be many surprises! Hopefully, at some point, we get to go to bed before the cycle starts over again the next day. After a few days of this work, oceanographers start to get really exhausted, which is when members of the team will sneak away for an hour or two during the ROV dive to nap or catch up on their scientific records, which document what we’ve seen and have being doing.
Innovation on the open ocean
This cruise is also special for another reason, not just the potential to find new species. I’ve been testing out a new method of cataloguing specimens right here in the field using my iPad and the FileMakerGo app. This trial run was the brilliant idea of our own museum specialist Linda Ward, who serves as our database guru. Linda loaded a bunch of catalogue numbers into the app and created a form for some basic collection data. I have a long list of preprinted catalogue numbers (the same numbers are loaded into the database), and I place one of these numbers with each new specimen, along with a ruler, before I take the picture. The catalogue number is assigned, and the photo is linked to the collection data. The best part is that I don’t have to write labels to drop in with the specimens (have you ever tried writing tiny labels on the open sea?); additionally, this process makes it much easier for me to keep track of all the different things I do with each specimen. Next, I just have to pack the new specimens for shipping back to NMNH. We will pick up the rest of this process in part 3 of this series, when we follow what happens to the specimens once they arrive back at the museum.
For now, the Robison team and I have a few more days left aboard the R/V Western Flyer and are sure to see several more exciting animals, to observe new things, and break more ground (or water, as the case may be)!
by Karen Osborn
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