Monterey Bay Aquarium Research Institute
2012 midwater ecology cruise

Day 6 – Seeing in the dark
July 18, 2012

Today was the last day of our expedition and we needed to be back in the harbor by 6:00 p.m., meaning that the remotely operated vehicle (ROV) must be on deck by 4:00 p.m. We didn't have a minute to lose! As we do everyday, today's dive started at 6:30 a.m. This would be our last chance to search for target species for our researchers. We got the chance to observe the fish Aristostomias scintillans that has bioluminescent organs producing red light under each eye. While most midwater species do not see red light, this fish can see this range of wavelength. Researchers believe that Aristostomias scintillans uses its red bioluminescent organs as night vision goggles for finding prey, and as a way for individuals of this species to see each other.

The red photophore is visible under the eye of this Arististomias scintillans.

During this expedition we have collected amphipods for Karen Osborn, curator at the Smithsonian National Museum of Natural History. She tells us more about her research on amphipods:

Hyperiid amphipods are small—up to approximately five centimeters (two inches) long—crustacean invertebrates that are abundant from the surface of the ocean down to the deepest depths, with particular abundance in the twilight zone or mesopelagic—200 to 1,000 meters (650 to 3,280 feet). At twilight-zone depths, available light is limited to increasingly dim and blue down-welling light and bioluminescence. In this zone, the competition to see and not be seen is a matter of life or death. As a result, hyperiids have huge variation in the shapes and function of their eyes, likely an evolutionary response to the complexities of the midwater optical environment.

Hyperiids generally have one or two pairs of compound (multiple part) eyes. In some hyperiids the dorsal eyes are greatly enlarged and cover the entire head. In others, optic fibers connect the lenses to the retinas, or they have cone-shaped retinas that allow a 360-degree field of view. Still others have retinas with mirrors that boost light collection. My postdoctoral fellow, Jamie Baldwin, who recently graduated from Duke University, and I will study the visual adaptations of hyperiids to life in the twilight zone by examining the morphology, physiology, and behavior of various species spanning the depth distribution and eye morphology of the group. Hyperiids live in close association with many gelatinous midwater animals, feeding on them, living on them, and brooding their young on them.

—Karen Osborn

Large specimen of the amphipod Scina sp.

The ROV was back on deck by 1:20 p.m. and as usual, the scientists took care of the sampled animals while the pilots hurried up to get everything ready for the second and very last dive of this expedition. During this dive the ROV recovered the MRS we left at the mooring 24 hours ago. We were back on deck at 4:00 p.m. Everyone was very busy tidying up the labs and getting everything ready to disembark.

As we are heading back to Moss Landing, I want to thank every single person on board (scientists, crew, pilots, and steward) for welcoming me so warmly on the Western Flyer and introducing me to the exciting world of midwater ecology. This cruise was a mind-blowing and unforgettable experience for me. I really hope to have the opportunity to join other marine research expeditions in the future!

The orange dot on the jelly Haliscera conica is a parasitic amphipod. We collected this jelly and its stowaway and found that it had eaten a large hole from the jelly's bell.

—Geraldine Fauville

Previous log


Day 6 Day 6
July 18, 2012
Seeing in the dark

Day 5 Day 5
July 17, 2012
Important observations

Day 4 Day 4
July 16, 2012
A squid's diet

Day 3 Day 3
July 15, 2012
Science never sleeps

Day 2 Day 2
July 14, 2012
Searching the deep sea

day one Day 1
July 13, 2012
Our first dive


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 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 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 Rob Sherlock
Senior Research Technician, MBARI

Rob is interested in the ecology of midwater invertebrates. He has worked in the Robison lab and been involved with the Midwater Time Series since he came to MBARI in 1996, identifying and quantifying mesopelagic animals and the changes in that community over time, depth and relative to other physical factors. He is looking forward to more sea-time this year than last!

kris walz 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 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 Henk-Jan Hoving
Postdoctoral Fellow, MBARI

Henk-Jan is a postdoc in the Midwater Ecology Group of Bruce Robison, Ph.D., investigating the life history strategies of pelagic cephalopods. Cephalopods have one reproductive cycle after which they die. Henk-Jan is interested in how long deep-sea cephalopods live, and how different species shape their reproductive strategies to optimize their single reproductive event.

Karen Osborn Karen Osborn
Smithsonian Institution

After completing her Ph.D. at University of California, Berkeley and MBARI, then a postdoc at Scripps Institution of Oceanography, Karen received a scientist position at the Smithsonian National Museum of Natural History. Her research focuses on the evolution of pelagic invertebrates, primarily polychaete worms and isopod crustaceans.

Bret Grasse
Monterey Bay Aquarium

Bret is an aquarist at Monterey Bay Aquarium where his job is to highlight and display a wide variety of marine organisms by providing the best possible conditions for each individual in captivity. Bret specializes in tropical systems and cephalopods.

Geraldine Fauville Geraldine Fauville
Summer Intern, MBARI

Geraldine has a master's degree in marine biology and is currently working toward a master's in education, communication and new technologies at the University of Gothenburg. She is a summer intern with MBARI's ITD division, investigating the potential for outreach and communication that social media holds.