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E-M:/ UM study on invasive species/ballastwater




July 10, 2007
Contact: Jim Erickson, (734) 647-1842, ericksn@umich.edu


U-M-led study: Rules to protect Great Lakes from ship-borne organisms are
inadequate; stronger measures advocated


ANN ARBOR, Mich.---Current rules aimed at minimizing the number of
nonnative species that hitchhike into the Great Lakes on oceangoing ships
are inadequate and often impractical, a University of Michigan researcher
and colleagues from five other U.S. and Canadian institutions have concluded.

The authors of a three-year study recommend that "saltwater flushing," the
practice of rinsing a ship's ballast tanks with deep-ocean water before it
enters the St. Lawrence Seaway, be added to a set of requirements called
the Code of Best Practices for Ballast Water Management. In 2002, the St.
Lawrence Seaway corporations in the United States and Canada adopted rules
making compliance with the code mandatory for entry into the seaway.

The study, released today (July 10), focuses on so-called NOBOB (no ballast
on board) ships, those that carry no pumpable water in their ballast tanks.
More than 90 percent of the cargo ships entering the Great Lakes through
the St. Lawrence Seaway are NOBOBs, and nonnative organisms can lurk in the
residual water and sediment left in the mostly empty ballast tanks.

Various approaches for sanitizing ballast water---using chemicals, heat,
ozone or ultraviolet radiation, for example---are being explored but have
not yet been adopted. In the interim, saltwater flushing provides an
inexpensive alternative that would likely kill most of the lingering
freshwater organisms in NOBOB ballast tanks, said U-M nutrient chemist
Thomas Johengen, one of the study's co-leaders.

"We think that saltwater exposure is an effective way to protect freshwater
systems. If we could apply it in every NOBOB, we think that we can close a
loophole," said Johengen, an assistant research scientist at U-M's School
of Natural Resources and Environment.

Johengen and project co-leader David Reid of the Ann Arbor-based Great
Lakes Environmental Research Laboratory (GLERL) worked with scientists from
the University of Windsor, Old Dominion University, the Smithsonian
Environmental Research Lab, and Jenkins & Associates Ltd. GLERL is part of
the U.S. National Oceanic and Atmospheric Administration.

The report, "Identifying, Verifying and Establishing Options for Best
Management Practices for NOBOB Vessels," was funded by the Great Lakes
Protection Fund, with additional support provided by the U.S. Coast Guard
and NOAA. Known informally as NOBOB-B, the study is a follow-up to one
(NOBOB-A) the same research team released two years ago.

NOBOB ships are loaded to capacity with cargo and carry no declarable
ballast water on board. But once they unload their cargo, they take on tons
of Great Lakes water for stability. If they then load cargo at another
Great Lakes port, they must discharge the ballast water, which is now a mix
of Great Lakes water, residual foreign water and sediment---as well as
stowaway organisms that can range from pathogenic microbes to mollusks and
fish.

At least 185 nonnative aquatic species have been identified in the Great
Lakes, and ballast water is blamed for the introduction of about 60 percent
of them, Johengen said.

The invaders include the notorious zebra mussel, a small but aggressive
Eurasian fish called the river ruffe, and two types of goby. Viral
hemorrhagic septicemia, which caused a huge Great Lakes fish kill last
year, may have arrived in transoceanic ships as well.

The latest NOBOB study included more than 70 salinity-tolerance experiments
designed to mimic saltwater flushing of ballast tanks and its effects on
various invertebrates---including larval stages of the zebra and quagga
mussels. The tests were conducted in Lake Erie, Lake Michigan, Chesapeake
Bay, San Francisco Bay and several European ports.

The experiments showed that many organisms originating in low-salinity
ports can be quickly eradicated from ballast water through exposure to
full-strength seawater.

"One of the key findings here has been to confirm that saltwater can be
quite effective at reducing the risk of invasions from ballast water," Reid
said. "It's not 100 percent effective against all types of organisms, but
it's far better than what's been going on, which has been basically no
regulation at all for NOBOBs."

The study also evaluated the effectiveness of the current Code of Best
Practices for Ballast Water Management.

The code requires vessels entering the Great Lakes to apply a
"precautionary approach" that includes minimizing ballast water uptakes at
ports where toxic algal blooms, known populations of harmful aquatic
organisms and pathogens, sewage outfalls, or dredging activities are present.

The team concluded that the real-world constraints of cargo loading and
unloading often make it impractical for crews to carry out the
environmental precautions. In addition, the precautionary measures "require
information on local water quality conditions that is not generally
available to the shipping industry," the researchers determined.

In 2005, the U.S. Coast Guard issued a policy statement encouraging
mid-ocean ballast tank flushing. Last year, Canada adopted management
regulations requiring that ballast water---including residual water in
NOBOBS---be treated with saltwater or salt---before the water is discharged
in the Great Lakes.

"This report is actually providing, finally, the basis of support for why
the Canadians did what they did," Reid said. "We've been keeping the
regulatory agencies apprised of our results all along, and they (Canadian
officials) actually jumped on it before we were completely finished."

Nearly 2,000 oceangoing vessels conducted Great Lakes trade via the St.
Lawrence Seaway between 1999 and 2006, according to the St. Lawrence Seaway
Development Corp.

Links:
Read the final NOBOB-B report:
< http://www.glerl.noaa.gov/res/Task_rpts/2004/aisreid04-1.html>http://www.glerl.noaa.gov/res/Task_rpts/2004/aisreid04-1.html

U-M School of Natural Resources and Environment:
< http://www.snre.umich.edu/ > http://www.snre.umich.edu/

Great Lakes Environmental Research Laboratory:
< http://www.glerl.noaa.gov/ > http://www.glerl.noaa.gov/

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[ballast]

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