• 13 - 19 June 2011


Day 7 – It is not the length of life, but the depth of life
June 19, 2011

Location: Monterey Canyon
Latitude: 36º 45.1001 N
Longitude: 122º 6.3000 W

Today the midwater lab wrapped up their week-long research expedition with two final dives. The first dive was an abbreviated one, only eight hours versus the regular 12, in which the primary mission was to collect study specimens as well as organisms of interest. We enthusiastically captured squid of the Gonatus variety, several Atolla jellies, a tomopterid worm, a pteropod (sea butterfly), and a rare deep-sea lobster larva!

The polychelid, lobster larva, just before it was collected in a detritus sampler by the ROV Doc Ricketts. This organism is a rare find as only a dozen have been observed over the last 18 years.

Although intrigued by the elusive polychelid larva, I am especially interested in coronate jellies of the genus Atolla. As the summer intern in the Midwater Ecology Lab, I will be focusing primarily on the these jellies, particularly the curious trailing filament, also referred to as a hypertrophied tentacle, which is morphologically unique to these scyphozoan jellies. Some researchers suggest that this structure may be used in prey capture or reproductive strategies. Over the next two months I will endeavor to test these hypotheses as well as explore new possibilities. Additional histological and experimental observations will hopefully shed some more light on this peculiar structure. The study of these creatures thus far has been producing much more questions than answers, but I feel that I am hot on their trail…ing tentacle.

Atolla wyvillei trailing its hypertrophied tentacle through marine snow in the midwater. The length of this tentacle may be nearly three to six times the diameter of the bell.

The second dive had a singular destination, the breathtaking midwater respirometry system (MRS) mooring at the 1400 meter site in Monterey Canyon, to retrieve the captive Sergestes similis for Kim Reisenbichler, who is measuring the oxygen consumption of these shrimp in situ. (See Day 1 entry for more details.) But of course we couldn’t pass up the opportunity to collect just a few more treasures from the deep on our ascent. The final dive of the Midwater Ecology Expedition, marking the end of our cruise, was alas bittersweet. As a first timer on the Western Flyer, the usage of the ROV as a window into the mysterious world of the deep sea was beyond anything I could have imagined. The ROV Doc Ricketts allowed us to view an almost alien environment and catch a glimpse of the incredible organisms that inhabit the meso- and bathypelagic depths. Although the exhilarating experience of collecting live animals and exploring the wonders of the deep is over, the journey is just beginning. With a fascinating array of video footage and organisms collected we can strive to add more pieces to the vast puzzle that is midwater ecology.

One of my personal favorites, of a squid belonging to the genus Taonius, displaying binocular orientation as we agitate him to get a closer look.

— Alexis Walker

Previous log


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.