• 13 - 19 June 2011


Day 4 – Deep dive reveals rare animals
June 16, 2011

Location: 2,300-meter site
Latitute: 36º 36.3159 N
Longitude: 122º 9.5354 W

Today we had a successful day at a deeper site (2,300 meters) within Monterey Bay. It was great, full of rare and interesting organisms! One of the first great finds was a small midwater octopod, Japetella diaphana. We don’t see this octopod very often, so when we do, it’s quite a treat! Unlike most octopods, they spend their entire lifecycle in the water column, meaning they never settle onto the seafloor. They are also bioluminescent, like many deep sea organisms. However, their bioluminescence is unique in that females are known to light up a ring around their mouths, which is thought to be a signal used in mating.

The midwater octopod, Japetella diaphana.

We also came across a fish that can possibly be described as the most opportunistic fish in the sea! Chiasmodon niger, the black swallower, has a large mouth that can engulf a fish similar to it’s own size. It’s gut can distend to hold in a huge prey item. In the deep sea, where food is scarce, this is a useful strategy to ensure that you won’t go hungry!

The black swallower fish with a full gut.
Chiasmodon niger can swallow prey similar to its own size.

The weird worm of the day was the Pigbutt worm, Chaetopterus pugaporcinus. Look at the picture, and you can see why it’s called that! The species’ Latin name actually means “resembling a pig’s rear”. This species was describe by a team of scientists led by Dr. Karen Osborn, one of the scientists on this expedition. This worm is unique because the other worms in this genus live on the seafloor in parchment-like tubes. Other Chaetopterid worms have larval forms that float in the water column, but Pigbutt is much larger (5 to 10 times larger) than any known Chaetopterus larvae. (image Cpugaporcinus.jpg – caption: ).

Pigbutt worm
The Pigbutt worm, Chaetopterus pugaporcinus is an unusual variation of a segmented polychaete worm.

— Susan von Thun

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R/V Western Flyer

The R/V Western Flyer is a small water-plane area twin hull (SWATH) oceanographic research vessel measuring 35.6 meters long and 16.2 meters wide. It was designed and constructed for MBARI to serve as the support vessel for ROV operations. Her missions include the Monterey Bay as well as extended cruises to Hawaii, Gulf of California, and the Pacific Northwest.

ROV Doc Ricketts

ROV Doc Ricketts is MBARI's next generation ROV. The system breaks new ground in providing an integrated unmanned submersible research platform, with many powerful features providing efficient, reliable and precise sampling and data collection in a wide range of missions.

Midwater respirometry system (MRS)

The MRS conducts oxygen consumption rate measurements in situ gauging the metabolism of animals without subjecting them to the stresses of transport to the surface. MRS has been modified to operate in deeper water with an expanded capacity, enabling respiration studies on animals that live deeper than 1,250 meters.

Detritus sampler

Detritus samplers are large plexiglass containers with lids that can be controlled by the pilot of the ROV and gently closed once an organism is trapped inside.


The CTDO is mounted on the ROV and takes in situ measurements of environmental parameters such as conductivity, temperature, depth, and oxygen concentration.

High frequency suction sampler

This sampler acts like a vacuum cleaner sucking up samples and depositing them into one of the 12 buckets.

 Research Team

Bruce Robison
Senior Scientist, MBARI

Bruce Robison's research is focused on the biology and ecology of deep-sea animals, particularly those that inhabit the oceanic water column. He pioneered the use of undersea vehicles for these studies and he led the first team of scientists trained as research submersible pilots. At MBARI, his research group has focused on the development of remotely operated vehicles as platforms for deep-sea science.

Kim Reisenbichler
Senior Research Technician, MBARI

Kim's general area of interest is the study of midwater and deep sea animals. He has developed many tools and techniques to observe, manipulate, and collect these organisms, and to maintain the animals in the lab.

Rob Sherlock
Senior Research Technician, MBARI

Rob studies the properties and organisms of the ocean's largest habitat, the midwater. His research group is learning more about the ecology of midwater organisms; their abundance and seasonal patterns, depth ranges and who eats whom. Rob enjoys watching mesopelagic animals with the HD (high definition) camera; animals that once would have come up as glop in a net can be seen to have delicate structure and complex behavior (e.g., squid inking or changing color, fish eyes that rotate to keep prey in sight, an amphipod carving up a pyrosome to make a home).

Kris Walz
Research Assistant, MBARI

Kris works with the Midwater Ecology group, analyzing ROV video transects between 50 and 1,000 meters in depth to identify biological organisms from all taxonomic levels, most of which spend their entire lives in the oceanic water column. Kris started working at MBARI in 1996 after finishing her Master's at UC Santa Cruz. She's looking forward to returning to sea this month to collect video transects and search for deep-sea lobster larvae from the family Polychelidae.

Susan von Thun
Research Technician, MBARI

Susan works in the MBARI video lab, where her primary responsibility is to watch video taken with MBARI's remotely operated vehicles (ROVs) and make observations about the organisms, behaviors, equipment, and geological features that she sees. While annotating video, she's become adept at identifying numerous deep-sea organisms, specializing in midwater organisms. She works closely with the midwater ecology group and the bioluminescence lab to expand her knowledge of the fish, jellies, cephalopods, and other groups in the midwater.

Henk-Jan Hoving
Postdoctoral Fellow, MBARI

Henk-Jan received his Ph.D in Ocean Ecosystems from the University of Groningen. Henk-Jan has developed an experimental program of both laboratory and in situ research that will chemically mark increments in the deposition of squid statoliths. Using the marks as temporal reference points, the pattern of deposition should allow him to determine the age of any squid.

Karen Osborn
Postdoctoral Fellow,
Scripps Institution of Oceanography

Karen's research interests include evolution of pelagic life, phylogenetics of marine invertebrates, and mechanisms of speciation in the open ocean and the deep sea. Karen is a former MBARI graduate research assistant and is currently a University of California President's Postdoctoral Fellow at Scripps.

Richard Young
University of Hawaii at Manoa

Richard is Professor Emeritus of Oceanography at the University of Hawaii. His research seeks to increase our understanding of cephalopod phylogeny and biodiversity, focusing in particular on cephalopod beaks, one of the more under appreciated features of all cephalopods, and their potential usefulness in phylogeny and identification.

Alexis Walker
Summer Intern, MBARI

Alexis is working with the Midwater Ecology Lab as a summer intern. Her interest in deep sea research has brought her to MBARI from UC Santa Cruz where she received her B.S. in marine biology, and more recently worked as a research technician.