Monterey Bay Aquarium Research Institute

Midwater Biology Logbook
Day 6: Cephalopod life history strategies
February 22, 2012

Even midwater biologists dive all the way down to the bottom sometimes. This morning we spent over an hour surveying the seafloor at 3,100 meters (10,000 feet) with the remotely operated vehicle (ROV). We collected some interesting purple enteropneusts, or acorn worms, for Karen Osborn. We even found some white ctenophores living on the bottom. They were attached to the mud with their tentacles deployed into the water. Both the acorn worm and the benthic ctenophore are undescribed species.

An unknown purple species of acorn worm.

On the way back up to the surface, Henk-Jan Hoving took the main scientist’s chair in the control room at 700 meters (2,300 feet) to search for interesting cephalopods. In less than five minutes he had spotted not one, but two specimens of the pelagic octopus, Japetella diaphana, which are rare in Monterey Bay, but we have had good luck finding them here in the Gulf of California.

Collecting Japetella diaphana in a detritus sampler with the ROV.

From Henk-Jan Hoving: We have been having a great cruise, and as a scientist who is interested in life history strategies of pelagic cephalopods (open-ocean squids and octopuses), it has been absolutely fascinating. We have been collecting squids and octopuses that are very poorly known, and in the process we are discovering totally new aspects of their biology.

We have noted two species of cephalopods that seem to occur here more frequently than in the Monterey Canyon. One of them is the pelagic squid Planctoteuthis danae. This animal has a peculiar body morphology; it has a very long and elaborate “tail” with numerous colorful tendrils. The function of this tail is unknown, but unlike other members in this group of squids, Planctoteuthis adults retain their “tail” rather than dropping it when they grow out of their juvenile stage. We know this because on day one of the expedition we were lucky enough to collect a near-mature female and a fully mature male—both sporting elaborate tails. To our knowledge these are the largest specimens ever collected of this species.

Henk-Jan Hoving uses a special tank to photograph a large female Japetella diaphana in the lab on the ship.

Planctoteuthis squid are seldom seen during ROV dives in the Monterey Canyon, perhaps once a year, but we have seen at least one on every dive this cruise. We have collected six of them, and I have dissected out the statoliths, which are calcareous (chalky) structures located near the eyes that help the squid with balance and orientation. My preliminary data suggest that the increments in the statolith, like the rings in a tree, probably represent one day in their life. By counting the number of increments in the statolith, I can determine how long it takes to grow from a juvenile of 20 millimeters mantle length to an adult of 150 millimeters mantle length.

Another species that is far more abundant in the Gulf of California than in the Monterey Canyon is a pelagic octopus, Japetella diaphana. So far we have encountered several of them every day, including mature males and females, and even a female that carried an egg mass. These specimens, in combination with animals we have collected in the Monterey Canyon, will enable us to answer fundamental biological questions like how many eggs do females carry? Do they spawn all eggs at once or do they have multiple broods? How do males and females mate? How does the female fertilize her eggs?

A brooding female pelagic octopus, Japetella diaphana. If you look closely, you can see the eggs between the tentacles.

These are critical aspects of the life history of these animals as they are semelparous (they have only one reproductive cycle in their lifetime) and finding mates in the big, dark ocean is presumably a challenge. One tactic that the female uses to overcome this problem is by storing sperm, which she can use when she is ready to spawn her eggs. The brooding of eggs in the middle of the water column decreases the chance of predation by animals from the bottom, while the animal is at the same time out of reach of deep-diving predators. Another reproductive tactic that this octopod employs is the use of bioluminescence to attract mates.

To further investigate the abundance and diversity of midwater organisms, Bruce Robison’s midwater ecology group is developing a new autonomous camera platform in order to record organisms without the disturbance of the bright lights and noise of remotely operated vehicles. The system consists of two deep-sea batteries powering a low-light camera that records continuous video, a recorder, and two red LED illuminators. Bait and a luminescent lure are hung in front of the camera to attract animals. The components are mounted on a frame that we deploy on the trawl wire of the A-frame on the Western Flyer and hang beneath the ship at night. We have deployed this system twice so far during this cruise.

Henk-Jan Hoving observes a squid collected with ROV Doc Ricketts.
Steve Haddock amd Henk-Jan deploy the towed camera at night after the zooplankton trawl has been recovered. The glowing blue light is a lure.
A large nudibranch, Bathydoris aioca, on the seafloor at 3,100 meters (10,000 feet). The red dots are from lasers on the ROV; they are 29 centimeters (11.5 inches) apart.

Can you guess what animal we captured on video with the towed camera? Stay tuned to our cruise log to find out.

—Kyra Schlining

Previous log Next 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.

Blue-water SCUBA diving rig

Blue water diving is a highly specialized mode of scientific diving that lets researchers observe, experiment, and collect delicate midwater organisms in situ. A weighted down line is suspended from the surface for the divers to attach the "trapeze" to which they attach their individual safety lines. Divers are attached to their safety lines by quick releases and a safety diver watches over all of them from near the trapeze throughout the dive.

Two-meter midwater trawl

A midwater trawl collects specimens while being towed behind the Western Flyer. Researchers have the option of trawling with the net open (as seen in this photo) or keeping the net closed until a particular depth is reached and then opening the net. The net can then be closed prior to recovery. This provides scientists with a discrete sample from a particular depth.

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.


R/V Western Flyer

Ian Young


George Gunther
Relief Captain, Legs 1 & 2


Matt Noyes
Chief Engineer


Andrew McKee
First Mate, Legs 1 & 2


Shaun Summer
Relief First Engineer


Paul Ban
Second Mate, Legs 1 & 2


Olin Jordan


Craig Heihn
Relief Deckhand


Jason Jordan
Relief Deckhand


Dan Chamberlain
Electronics Officer


Patrick Mitts


ROV Doc Ricketts

Knute Brekke
Chief ROV Pilot


Mark Talkovic
Senior ROV Pilot


Randy Prickett
Senior ROV Pilot


Bryan Schaefer
ROV Pilot/Technician


Eric Martin
ROV Pilot/Technician


 Research Team

Steve Haddock
Chief Scientist

Steve Haddock studies the biodiversity and bio-optical properties of gelatinous zooplankton (various types of jelly-like animals). He uses molecular and morphological traits to examine the relationships of rarely-studied, deep-sea comb jellies and other open-ocean drifters, many of which are new to science. These animals also are able to make their own light (bioluminescence); Steve is interested in the genes involved in light-production.

Lynne Christianson
Senior Research Technician

Lynne works in Steve Haddock's laboratory and her research focuses on exploring the biodiversity of marine zooplankton, especially cnidarians and ctenophores (jellies) and phaeodarians (radiolarians). She uses the tools of molecular biology to aid in the identification of these animals, to study their evolutionary relationships, and to investigate the origin and function of bioluminescence and fluorescence. In addition to assisting in the collection and examination of animals from ROV dives, trawls, and blue-water scuba dives, her main job will be cruise logistics. Her goal is to make this cruise as successful as possible for all the scientists on board! She's looking forward to seeing how the diversity of midwater animals in the Gulf of California compares to those in the Monterey Bay.

Henk-Jan Hoving
Postdoctoral Fellow

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. During the expedition in the Gulf of California he hopes to collect various pelagic cephalopod species and determine their age using their statoliths. Statoliths are hard, calcareous masses in the squid's organs of balance in which increments are periodically laid down (similar to rings in a tree). Additionally, a baited camera system will be deployed over the side of the ship to attract and record midwater fish and squid. The species seen by this camera system will be compared with the species encountered using remotely operated vehicles (ROVs).

George Matsumoto
Senior Research Specialist

George works in the fields of research and education. He is interested in a wide variety of gelatinous organisms and is focusing on Bathochordaeus—a large larvacean that has been studied in Monterey Bay using ROVs, but one that we hope to find and work with on scuba while in the Gulf of California. As a senior education and research specialist at MBARI, George's role involves several different projects: seminar coordinator, summer internship coordinator, livelink mentor, distance education, links between the research institute and other partners, and other projects that haven't begun yet. He is interested in the open ocean and deep-sea communities with particular emphasis on invertebrates. Specific areas of interest include: Ecology and biogeography of open ocean and deep sea organisms; Functional morphology, natural history, and behavior of pelagic and benthic organisms; Systematics and evolution of ctenophores and cnidarians (molecular phylogeny).

Kyra Schlining
Senior Research Technician

Kyra is a senior research technician in the video lab at MBARI. Her main responsibility, both on shore and at sea, is to manage and annotate the video footage recorded during MBARI ROV missions. Kyra specializes in identifying deep-sea organisms and describing their behaviors, as well as, recording observations on habitat and equipment. On the ship,she will also assist with processing biological samples and writing up the cruise logs. Kyra's duties in the video lab also include assisting scientists with accessing the data from the video database for publications, editing video from our archives using Final Cut Pro, and presenting current MBARI research to the public, mainly through our sister organization, the Monterey Bay Aquarium.

Meghan Powers
Graduate Research Assistant

Meghan is a doctoral candidate at University of California, Santa Cruz working in Steve Haddock's lab. Her research is focused on understanding the molecular biology and evolution of bioluminescence in a variety of deep-sea zooplankton including cephalopods, chaetognaths, and jellyfish.

Stephanie Bush
Postdoctoral Fellow
University of Rhode Island

Stephanie joined the Seibel Lab at the University of Rhode Island as a postdoctoral researcher after finishing her graduate work in MBARI's Midwater Ecology Lab and the Caldwell Lab at University of California, Berkeley. She is broadly interested in marine organismal ecology, and her current research explores animal physiological adaptations to living in oxygen minimum zones and how we can predict the response of marine organisms to ocean warming. Additionally, she is part of collaborative effort to study animal camouflage in open water, focusing particularly on the polarization components. She is also interested in the connectivity between populations of planktonic animals and how it relates to speciation and biodiversity in the open ocean.

Rebeca Gasca
El Colegio de la Frontera Sur, Unidad Chetumal, Mexico

Rebeca's research is on the biology and ecology of zooplankton, especially of siphonophores and hyperiid amphipods. She is interested in community changes related with water masses and environmental phenomena like El Niño. Also, the symbiotic associations between gelatinous zooplankton and hyperiids have been among her main interests and this kind of expedition represents an opportunity to observe those behaviors in situ.

Karen Osborn
Smithsonian National Museum of Natural History

After completing her Ph.D at UC 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. During this expedition she will be working on drifting acorn worms, systematics of tomopterid polychaetes, and the feeding and population genetics of munnopsid isopods.

Erik Thuesen
Evergreen State College

Erik Thuesen is a member of the faculty in Zoology at The Evergreen State College. His research focuses on the ecological physiology and biodiversity of marine invertebrates. He has studied many kinds of gelatinous zooplankton, including chaetognaths, ctenophores, and medusae. He is particularly interested in the physiological and biochemical adaptations to life in marine environments, such as the deep sea and estuaries. He received a B.S. from Antioch College, a M.A. from the University of Tokyo and his Ph.D. from the University of California at Santa Barbara. At Evergreen, he teaches invertebrate zoology, symbiosis, biodiversity and marine science.

Last updated: Feb. 27, 2012