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Ocean Research

2018:  FEB

May 2017 Issue

Expedition to Support
US, Cuba Sister Sanctuaries

Harbor Branch Oceanographic Institute’s Dr. Shirley Pomponi and Dr. Joshua Voss, joined by Dr. Peter Ortner (University of Miami) and Fernando Bretos (Frost Museum of Science), traveled to Havana, Cuba, to make final arrangements for the upcoming CIOERT expedition that will be circumnavigating the Cuba archipelago.

The cruise will kick off an exploration and research collaboration between Harbor Branch, University of Miami Cooperative Institute for Marine & Atmospheric Studies, The Frost Museum, the Cuba National Center for Protected Areas, the University of Havana Center for Marine Studies, and the Cuba Institute of Oceanology.

The expedition will be the first activity in support of the memorandum of understanding between NOAA, the U.S. National Park Service and the Cuba National Center for Protected Areas establishing Sister Sanctuaries between two marine protected areas in Cuba and the Flower Garden Banks and Florida Keys National Marine Sanctuaries in the U.S.

The expedition will depart May 15 from Miami and return June 9.

Bacterial Respiration
Can Add to Ocean Carbon

The oceans absorb carbon dioxide from the air, but when their deep waters are brought to the surface, the oceans themselves can be a source of this greenhouse gas.

Wind patterns and the Earth’s rotation drive deepwater—and the carbon dioxide it sequesters—upward, replacing surface water moving offshore. This upwelling occurs on the west coasts of continents as part of the natural rise and fall cycle of carbon dioxide levels in the surface ocean.

But when carbon dioxide levels rise, ocean pH falls, causing ocean acidification.

UC Santa Barbara researchers found that the additional carbon dioxide and corresponding drop in pH increases the respiration of bacteria. When these microbes respire, the organic carbon they consume is converted back to carbon dioxide, which can go back into the atmosphere or dissolve in the surface ocean. The elevated bacterial respiration could limit the oceans’ ability to store organic carbon by converting it back to carbon dioxide. This affects the food web and ocean biogeochemical processes.

Retreating Arctic Ice
Affects Polar Cod

Polar cod is a major source of food for seals, whales and seabirds in the Arctic food web. Under the ice of the central Arctic, juvenile polar cod are heavily dependent on ice algae. As a result, retreating sea ice could have far-reaching impacts on the food web, as confirmed by an international team of researchers led by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research.

Young fish between one and two years old live in cracks and crevices under Arctic ice. They drift along with the ice from northern Siberia to the central Arctic, and they feed on amphipod crustaceans, which in turn feed on ice algae, so there is a direct relationship between the polar cod and the ice algae, which could ultimately threaten polar cod survival.

Sonar Helps Survey
Estonian Waters

The Estonian Maritime Administration identifies potential dangerous wrecks in Estonian waters to ensure safe navigation.

Wrecks can pose an environmental threat because of their cargo and fuel. High-resolution multibeam sonar systems help find and identify such wrecks.

Surveys are conducted by the Hydrographic Department of the Estonian Maritime Administration, which operates four survey vessels, three of which are equipped with Teledyne RESON SeaBat sonar systems. The SeaBat 7125 has surveyed several wrecks in Estonian waters.

All of the collected and processed data from surveys enter the hydrography information database. Data layers from this database are available at https://gis.vta.ee/nutimeri.

So far, the Hydrographic Department has charted 47 percent of Estonia’s maritime areas, with a goal to chart 100 percent.

New Strategies Needed
For Ballast Water

Marine biologists from the Smithsonian Environmental Research Center (SERC) discovered in a new study that open-ocean ballast water exchange to manage invasive species is not as effective as previously thought.

Currently, open-ocean exchange is the main ballast water management strategy, which entails flushing out ballast water in the open ocean to remove most coastal organisms and replace it with water more than 200 naut. mi. from shore.

Any open-ocean organisms picked up during this process are unlikely to survive in ships’ destination ports and coastal waters. This strategy provides a stopgap until new technologies can further reduce species transfers.

Since 2004, the U.S. Coast Guard has required most commercial ships entering the U.S. from overseas to conduct open-ocean exchange before discharging ballast in U.S. ports.

SERC biologists examined the ballast water of large bulker ships entering the Chesapeake Bay for a period of 20 years, comparing samples before and after the open-ocean exchange rule went into effect. The concentrations of potential coastal invaders that scientists found in ballast water were five times higher in recent ships.

Overseas ships have discharged almost five times more ballast water into the Chesapeake Bay in 2013 than in 2005, mostly from bulkers that return loaded with overseas ballast water.

From 2005, the more coal the Chesapeake exported, the more bulkers came into its ports. The surge in global trade is causing increases in the concentration of foreign organisms in ballast water and total ballast water discharged in the bay.

Onboard technology, such as UV radiation, could be more effective to eradicate invaders. The U.S. Coast Guard has set new discharge standards for treatment technology and has already approved three onboard treatment systems. In addition, 54 nations have signed the Ballast Water Management Convention, effective September 2017, which limits the concentrations of various organisms ships can have in ballast water before discharge.

2018:  FEB

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