Monterey Bay Aquarium Research Institute
2009 Pacific Northwest Expedition


Leg 2 Logbook - Midwater Ecology
Day 6 — Last dive for Leg 2
July 30, 2009

Latitude 44 degrees 49.7727 minutes N
Longitude 125 degrees 25.0469 minutes W

Our last dive for this expedition. It’s been a very short but very productive dive series. We are due back at port in Newport at 1630 hours so we have moved a little closer to Newport trying to maximize our dive time before we have to recover the ROV and return to shore. The pilots were kind enough to let us start earlier, so with a 6:00 a.m. splash time, we got into the water and started our work.

The goal for today’s dive was to find an unusual squid—Octopoteuthis—the eight-armed squid. One of the researchers on board (Stephanie Bush) is finishing up her doctoral dissertation and one of the topics of her research is this squid and we were hoping to find one more animal for her to observe before she leaves us to start a postdoctoral fellowship at the University of Rhode Island.

The dive was a short but exceptional one. We saw some amazing fish like this Tactostoma, ctenophores, a Vampyroteuthis (a deep-dwelling cephalopod that is neither a squid nor an octopus), and several giant larvaceans in the genus Bathochordaeus.

A closeup view of the head of Tactostoma, a beautiful midwater fish with very big teeth.

While most larvaceans are quite small, less than a couple centimeters or so, Bathochordaeus are more like the size of your forefinger and the mucous houses they build to filter food are up to one meter in diameter. Bathochordaeus are hermaphrodites—individuals produce both eggs and sperm—and these happened to have both. It’s rare to see so many fecund individuals as we have on this cruise series and on this dive in particular, but it will help us to finish some work we’ve been doing on their sexual habits and reproduction.

A larvacean (Bathochordaeus) with both eggs and sperm visible in the head region.

—Rob Sherlock


Previous log

Leg 2
 Equipment

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.

High-frequency suction sampler

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


Detritus sampler

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


Spatulator

Used in combination with the High-Frequency Suction Sampler (HFSS) and Detritus Samplers, the spatulator flips items off the seafloor that are then vacuumed into the High Frequency Suction Sampler or collected with the Detritus Samplers.

Midwater acoustic current meter

The current meter is held by a small standalone fixture and measures the magnitude and direction of the currents about 1 meter above the seafloor.


 Research Team

Senior Scientist, Bruce Robison Bruce Robison
Senior Scientist, MBARI

Bruce Robison's research interests are centered on the biology and ecology of deep-sea animals, particularly those which inhabit the oceanic water column. He has pioneered the use of undersea vehicles for these studies and led the first team of scientists trained as submersible pilots for research in midwater. His midwater research program is presently addressing the ecology of gelatinous animals in the deep sea. This group includes ctenophores, medusae, and siphonophores, animals which cannot be investigated accurately with conventional sampling methods, but which play dominant roles in mesopelagic ecology. Related studies include trophic structure, physiology, and the behavior of midwater animals including fishes and squids. Behavioral studies are also investigating the ways that animals use bioluminescence in the deep sea, with both laboratory and in-situ observations.

Graduate Student, Stephanie Bush Stephanie Bush
Graduate Student, University of California, Berkeley

Stephanie is a doctoral candidate at UC, Berkeley, in the lab of Dr. Roy Caldwell. In collaboration with Bruce Robison and the MBARI Midwater Ecology lab, her dissertation research focuses on deep-sea squid ecology, particularly their defensive behaviors.

Senior Research Technician, Rob Sherlock 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).

Senior Research Technician, 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.

Senior Education and Research Specialist, George Matsumoto George Matsumoto
Senior Education and Research Specialist, MBARI

George 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; and systematics and evolution of ctenophores and cnidarians (molecular phylogeny). George also runs a wide variety of education programs at MBARI

Research Technician, 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.

Reseach Assistant, 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 for the first time since starting a family.