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Ocean Research


October 2016 Issue

Healy Completes First
Mission in Arctic

The U.S. Coast Guard Cutter Healy completed the first of three missions working on groundbreaking science in the Arctic Chukchi Sea. The mission yielded the discovery of new jellyfish species in the Chukchi Borderlands and of a new genetic order of benthic ctenophore, and the documenting of a new reproductive behavior of comb jellyfish. The Global Explorer ROV was used to collect hundreds of living specimens for lab study. Other sampling gear enabled assessment of the biological diversity of the entire ecosystem.

Healy departed for its second Arctic mission, using an array of acoustic bottom moorings to collect data on how climate change and decreased ice coverage is affecting the Arctic Ocean.

The third mission, scheduled for mid-September, involves multibeam sonar mapping and bottom dredging in the Bering Sea and Arctic Ocean to further support the demarcation of the Extended Continental Shelf to support U.S. territorial claims in the Arctic.

The findings help shed light on this rapidly changing region.

Modified SeaTag-MOD
Tracks Great White Sharks

Researchers at the Monterey Bay Aquarium (MBARI) are studying Great White Sharks commonly found along the central coast of California during fall and winter. The sharks leave in the spring to a remote location in the middle of the Pacific Ocean.

Desert Star Systems’ SeaTag-MOD, a modular pop-up satellite tag, can provide migration pattern details via built-in depth, accelerometer, magnetometer and temperature sensors. A new PSAT tag design for MBARI’s shark research involved a video camera that could attach to the shark for months, withstand depths of more than 3,000 ft., and could sense shark movements to record certain behavior footage. A hook was made in the SeaTag-MOD for plugging in MBARI’s shark behavior detection algorithm. Pressure, light and acceleration sensors in the SeaTag-MOD were maintained while removing those parts from the camera controller. A software framework was created to use archival data to write the behavior detection algorithm, which then translates to a portable program that validates the ported algorithm against the archival data. This code is compiled into the SeaTag-MOD and runs in real time.

Tagging is to start December or January, when most of the sharks leave the California coast. The tags will remain in “sleep mode” until sharks reach their hotspot in the middle of the Pacific.

Barnacle-Bacteria Research
Could Counter Biofouling

The coating of barnacles and other growth, or biofouling, along the bottom of boats slows down ships and impedes the readiness of emergency response and military vessels. A new study by San Diego State University biologist Nick Shikuma identifies key developmental steps biofoulers must take to metamorphose from larvae to adults. Understanding this process could lead to new technologies to prevent the organisms from attaching to ships in the first place. It’s during the metamorphic stage that biofoulers settle upon a surface.

The study sequenced the genome of the tubeworm Hydroides elegans, a common biofouler that leaves behind calcium carbonate tubes that stick to boats. Shikuma introduced P. luteoviolacea bacteria to the tubeworms to kick off their metamorphosis and analyzed the worms’ gene expression across different stages of development.

A particular chain of proteins known as the MAPK signaling pathway was found activated during metamorphosis. A normal interaction between the bacteria’s spears and the tubeworm’s MAPK pathway appeared necessary for the tubeworms to successfully reach their adult stage.

Sonardyne Tech for
SuBastian ROV

The SuBastian ROV was built by the Schmidt Ocean Institute (SOI), a private nonprofit, to provide scientists new opportunities to explore and study the ocean. Capable of diving to 4,500 m, the vehicle’s equipment includes a reconfigurable payload skid for deploying and recovering experiments, a 4K ultrahigh-definition camera capable of streaming live video to the surface and a comprehensive suite of scientific sampling sensors.

When SuBastian entered service this summer, it was operated from SOI’s RV Falkor, which has been operating with Sonardyne’s Ranger 2 USBL acoustic positioning system since 2012.

SOI and Sonardyne worked together to configure an integrated navigation solution for SuBastian comprising a SPRINT INS, Syrinx 600-kHz DVL and a Wideband Mini Transponder (WMT).

SV3 Wave Glider for
Fish Aggregation Study

FAU Harbor Branch Associate Research Professor Dr. Laurent Chérubin is working on a project using the Liquid Robotics SV3 Wave Glider to study fish aggregations in the NOAA Florida Keys National Marine Sanctuary. The project builds on past research and monitoring in the sanctuary and focuses on connectivity between the network of marine reserves in the Dry Tortugas region.

The goal of the wave glider mission was to record ambient noise, fish and marine mammal sounds and record oceanographic conditions in the vicinity of spawning grounds for snappers in the summer and groupers in the winter.

Mediterranean Sponge
Builds Chemical Shield

University of Delaware postdoctoral researcher Eva Ternon and colleagues at other universities report new evidence that the Mediterranean encrusting sponge Crambe crambe (C. crambe) emits chemical cues from its tissues to generate a chemical shield, most likely for defense and communication purposes.

The benthic sea sponges constantly produce and release toxic compounds into the surrounding water by expelling small cells, spherules, each containing up to 136,000 molecules.

The researchers concluded that the toxins are stored in sponge cells and are most likely biosynthesized by them.

These small toxic balls diffused and settled around the sponge, leading to a shield of toxic compounds to deter predators and prevent occupation of the seafloor by other benthic species.


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Sea Technology is read worldwide in more than 110 countries by management, engineers, scientists and technical personnel working in industry, government and educational research institutions. Readers are involved with oceanographic research, fisheries management, offshore oil and gas exploration and production, undersea defense including antisubmarine warfare, ocean mining and commercial diving.