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December 2011 Issue

Unequal Ballast Water Discharge Impacts Found on US East, West and Gulf Coasts
Open-ocean exchanges, the process in which large vessels swap out ballast water at least 200 nautical miles from land to flush out invasive species, is not equally effective across the U.S., according to a recent study. Ecologists from the Smithsonian Environmental Research Center (SERC) found ports on the U.S. East Coast and the Gulf of Mexico are significantly less protected than West Coast ports.

Whitman Miller and a team of scientists from SERC looked at all international ships entering the contiguous U.S. over three years. Published in November in BioScience, the study analyzed approximately 105,000 vessel reports from January 2005 to December 2007. While most ships opted not to discharge any water, a significant number continued to dump unexchanged or improperly exchanged water into their ports of entry, the study said.

The study found that the gulf and the East Coast received much larger fractions of unexchanged ballast water than the West Coast. Roughly 5 percent of the discharged water on the West Coast had not undergone open-ocean exchange. By contrast, 21 percent of the discharged water in the gulf and 23 percent on the East Coast went unexchanged.

Much of the problem comes down to simple geography. Depending on the transit route, a ship may not have the time or space to conduct open-ocean exchange. Some incoming ships on the East and Gulf coasts may not even pass through the open ocean at all. This points to the need for another solution, the study said.

"Given the geographic constraints of shipping, and the complexity of the invasion process, it is clear that we need to move to onboard ballast water treatment technologies that will allow ships to operate anywhere in the world without fear of releasing harmful invasive species," Miller said. For more information, visit www.serc.si.edu.

NOAA Examines Potential Link Between Dolphin Deaths and Deepwater Horizon
Pathology experts contracted by NOAA are investigating the causes of a higher than expected level of dolphin strandings and deaths along the northern Gulf of Mexico, including any potential connection to the Deepwater Horizon oil spill, NOAA reported in October.

Since February 2010, 580 dolphins have been stranded. Scientists tested 21 of these dolphins so far for Brucella, a bacterium commonly found in populations of marine and terrestrial animals. The bacterium was found in two adult dolphins and three fetuses that had died off the Louisiana coast between June 2010 and February. Scientists are still investigating the causes of the other 16 deaths.

The recent die-offs could be caused by the bacterium becoming more lethal, NOAA scientists said. Dolphins could also be more susceptible to bacteria, making illness more likely and more severe.

"Severe environmental stress, including from exposure to oil, could have reduced the animals' ability to fight infection," said Teri Rowles, coordinator of NOAA's National Marine Mammal Health and Stranding Response Program. "Right now, there is insufficient information to distinguish between these possible explanations for the increases in mortality of dolphins in the northern Gulf of Mexico." For more information, visit www.noaa.gov.

Giant Amoebas Found at 10,000 Meters' Depth
Scientists on a Scripps Institution of Oceanography expedition identified gigantic amoebas called xenophyophores at the Mariana Trench, the institution announced in October.

Scripps researchers and National Geographic engineers in July deployed autonomous Dropcams, untethered free-falling/ascending landers equipped with digital video and lights. The Dropcams, developed by National Geographic engineers, utilize a thick-wall glass sphere designed to withstand more than 8 tons per square inch of pressure. The devices were baited and used "camera traps" to capture imagery of approaching marine life.

The team documented the deepest known existence of xenophyophores at depths up to 10,641 meters within the Sirena Deep of the Mariana Trench, Scripps said. These single-celled animals are known for their size (often larger than 10 centimeters), abundance on the seafloor and their role as hosts for a variety of organisms. The previous depth record for xenophyophores was about 7,500 meters in the New Hebrides Trench.

"The identification of these gigantic cells in one of the deepest marine environments on the planet opens up a whole new habitat for further study of biodiversity, biotechnological potential and extreme environment adaptation," said Doug Bartlett, Scripps marine microbiologist.

Scripps researchers said they hope to someday capture such deep-sea animals for study in high-pressure laboratory aquariums that replicate the trench environment. For more information, visit www.sio.ucsd.edu.

US Residents Value Hawaii's Reefs at $33B Per Year
Americans assign an annual economic value of $33.57 billion for the coral reefs of the main Hawaiian Islands, according to a NOAA-commissioned study published in October.

The agency said it will use the study to provide a reliable estimate of the value of Hawaii's coral reef ecosystem, which has experienced increasing stress from growing urban populations and other pressures. In the study, the total economic value includes passive use values (e.g., the willingness to pay to protect the coral reef ecosystem for future generations) as well as direct use values (e.g., snorkeling over a reef or consuming fish supported by the reefs).

"The study shows that people from across the United States treasure Hawaii's coral reefs, even though many never get to visit them," NOAA administrator Jane Lubchenco said. "It illustrates the economic value of coral reefs to all Americans, and how important it is to conserve these ecosystems for future generations."

The study surveyed more than 3,200 households in both coastal and noncoastal areas via the Internet from June to October 2009. To estimate the reef's economic value to the public, the study team presented participants with two specific measures to protect and restore coral reef ecosystems. One measure aimed to reduce effects on coral ecosystems from fishing and another targeted repairing reefs damaged by ships. For more information, visit www.noaa.gov.


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