Seafloor Biology Logbook
Day 4: Seafloor transects
March 4, 2012
El Norte blew through the night, but by morning was showing signs of backing off. Thirty knots overnight dropped to 25 by mid-morning. Just before lunch we were able to resume operations and launched the ROV Doc Ricketts for another dive in Guaymas Basin to study the seabed. We dove to 970 meters (3,200 feet) and observed the seabed for a while, identifying the local fauna, looking for odd animals rarely seen in California waters.
We performed benthic ‘video transects,’ where we zoom in on the seabed so that the width of the video images is about one meter wide. We use a pair of parallel red lasers to help with this. The lasers shine two red dots on the seabed that are 29 centimeters apart and provide us with a sort of scale to measure the size of objects we observe. We then fly slowly over the seabed in one direction for 500 or more meters. Later, video analysts at MBARI will identify and count all of the animals and seabed characteristics observed along the transect, providing a quantitative measure of the abundance and density of all of the organisms we can identify.
Late in the day we released the benthic respirometer system (BRS) from the seabed. It rose to the surface at a speed near 35 meters per minute, and arrived in just over 30 minutes. We eased the ship close to the BRS bobbing at the surface, grappled it with a line, and carefully lifted it aboard using the A-frame and winch on the stern of the ship. We’ll download the data and analyze the rates of oxygen consumption for the sea cucumbers (Pannychia sp.) placed in the chambers two days ago.
We are now headed for the Salsipuedes Basin, a location about 120 kilometers (75 miles) north. The Salsipuedes Basin is known for its difficult and treacherous currents. We plan to deploy the BRS in the basin tomorrow morning, then dive the ROV Doc Ricketts to load the BRS with animals and explore the seabed. Hopefully we’ll run into unknown hydrothermal vent or seep locations. They have been discovered in several locations along the Gulf of California, and are somewhat expected since the gulf is actively spreading, slowly opening the distance between Baja California and mainland Mexico.
— Jim Barry
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 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.
You can see the manipulator arm at the upper left side of the photo and the sample drawer with partitions in the lower left. The drawer is shown open on deck, full of rocks. Normally it is closed when the vehicle is operating and only open when a sample needs to be stowed. The partitions help us keep the rocks in order. The rocks look so much alike, all covered in manganese, it is important to know where each rock came from.
A push-core looks like a clear plastic tube with a rubber handle on one end. Just as its name implies, the push core is pushed down into loose sediment using the ROV's manipulator arm. As the sediment fills up the core, water exits out the top through one-way valves. When the core is pulled up again, these valves close, which (most of the time) keeps the sediment from sliding out of the core tube. When we bring these cores back to the surface, we typically look for living animals and organic material in the sediments.
Oxygen consumption (a measure of biological activity) of the organisms living in the sediment is measured using a benthic respirometer system (BRS). This instrument is used in situ (in place on the seafloor).
Johnson Flux Chamber System
Measures fluxes of CO2 and methane in terrestrial plant communities.
This sampler acts like a vacuum cleaner sucking up samples and depositing them into buckets.
Canvas bags on a T-handle for collecting gravel or other materials that fall out of a push-core.
R/V Western Flyer
ROV Doc Ricketts
Jim Barry is a senior scientist at MBARI whose research program focuses on the effects of climate change on ocean ecosystems. In addition to climate change, his research interests are broad, spanning topics such as the biology and ecology of chemosynthetic biological communities in the deep sea, coupling between upper ocean and seafloor ecosystems in polar and temperate environments, the biology of deep-sea communities, and the biology of submarine canyon communities. Jim has helped inform Congress on ocean acidification, ocean carbon sequestration, and climate change by speaking at congressional hearings, briefings and meetings with congressional members.
Ken's research interests are focused on the development of new analytical methods for chemicals in seawater and application of these tools to studies of chemical cycling throughout the ocean. Over the past 15 years, Ken's Chemical Sensor Program at MBARI has developed a variety of sensors and analyzers that operate in situ to depths of 4,000 meters. These instruments have been used to study processes ranging from the distribution of sulfide in deep-sea hydrothermal vent systems, to nitrate in coastal ponds surrounded by intensive agricultural activities.
Kurt Buck specializes in quantitative enumeration, ecology, and imaging of marine protists and bacteria. Upper water-column communities from Antarctic and Arctic sea ice to equatorial regions were his initial focus. He is currently working with deep-sea sediment communities including those from hypoxic zones.
Bob Herlien is a senior software engineer at MBARI. He is project manager for the Respirometer Upgrade project, which includes the Benthic Respirometer System (BRS) being deployed on this cruise. He is also principal software designer for that system. His responsibilities on this cruise include configuring the BRS for each deployment and assuring that it's in good working shape.
Linda specializes in the ecology of small animals that live in marine sediments (macrofauna), and larger invertebrates and fishes that live on the seafloor or just above it (megafauna). She conducts habitat characterization studies in benthic (seafloor) ecosystems using underwater video and by collecting deep-sea animals. She hopes to find some new and interesting animals in the unique habitats we are visiting on this cruise.
Chris supports Jim Barry's Benthic Biology and Ecology, and Free-Ocean CO2 Enrichment research projects. On this expedition, Chris's responsibilities are varied, from collection and curation of invertebrates used in Benthic Respiration System metabolic rate and manipulative oxygen and pH studies, to Geographic Information System work, to operation of the dissolved inorganic carbon analyzer. Chris's recent work focuses on the effects of ocean acidification on invertebrate behavior.
Patrick has worked at MBARI since its beginning in the fall of 1987. Prior to his move to MBARI, he spent seventeen years at Duke University Marine Lab investigating heavy metals in the marine environment. He currently works with Jim Barry in the design and construction of sampling gear used on the ROV to collect benthic animals, in addition to processing benthic samples and conducting carbon-hydrogen-oxygen (CHN) analyses.
Josi is a postdoctoral fellow in Jim Barry's Benthic Biology Group. Josi's research is focused on exploring the effects of global climate change—specifically, ocean acidification and hypoxia—on the deep-sea urchin Strongylocentrotus fragilis. Josi looks for effects of environmental change on urchin physiology, behavior, and population/ community structure. During the Gulf of California expedition, Josi will investigate S. fragilis from 200-1200 meters in the Sea of Cortez to identify differences in this population's age structure, depth distribution, physiology, and behavior, as compared to S. fragilis found in the considerably different conditions of the Monterey Bay Canyon System. Josi hopes to use these comparisons of S. fragilis living in two very distinct climates, to better predict the effects of global climate change on community structure and ecosystem function.
Yossellin Tapia De la O
Yossellin is working on an ecological study of ophiuroids (brittlestars) associated with bacterial mats of the cold methane seeps in the Sonora Margin of Mexico. This study will contribute information about morphological variations, abundance, biomass, and habitat preferences of the ophiuroids.
Adriana is a doctoral student at Posgrado en Ciencias del Mar y Limnología, UNAM. Her project looks at the abyssal distribution in the Atlantic Equatorial Belt taking as example the crustacean fauna of the asphalt volcano, Chapopote, in the southern Gulf of Mexico, with emphasis on Alvinocaris muricola and Munidopsis geyeri species.