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GLIN==> NOBOB Best Management Practices Final Report available



The Great Lakes NOBOB research team is pleased to announce the availability of a recently completed final report on a three-year study entitled, “Identifying, Verifying, and Establishing Options for Best Management Practices (BMPs) for NOBOB Vessels” (short title:  NOBOB-B). 

A complete copy of the report can be downloaded from the project web-site at:
http://www.glerl.noaa.gov/res/Task_rpts/2004/aisreid04-1.html

The study was primarily funded by the Great Lakes Protection Fund, with supplemental funding and support by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Coast Guard.  The research project was a bi-national, multi-institutional collaboration and was comprised of scientists from NOAA-Great Lakes Environmental Research Laboratory, University of Michigan, University of Windsor, Old Dominion University, Smithsonian Environmental Research Laboratory, and Philip T. Jenkins & Associates Ltd.

The study was undertaken to examine the extent to which commercially operating ships realistically apply the practices put forth in the “Code of Best Practices for Ballast Water Management” (hereafter “the Code”) adopted for the Great Lakes by the Shipping Federation of Canada and the (U.S.) Lake Carrier's Association in 2000, and to examine the effectiveness of these and suggested enhanced management practices at reducing the risk of new species introductions in the Great Lakes, especially from NOBOB (no-ballast-on-board) vessels. 

The enhancements to be tested included the following new or modified practices: 1) when in locations that appear undesirable for ballasting (BMP #6a-f), use the minimum possible ballast in the fewest tanks possible and complete ballasting after transit out of the undesirable conditions; 2) when carrying ballast, discharge and replace poor quality ballast water with cleaner water as soon as possible to minimize the amount of sediment accumulation; and 3) regularly perform a saltwater flush of all empty (NOBOB) ballast tanks when transiting the ocean. 

In particular the study sought to evaluate the effects of BMPs on organism density and viability (including resting stages), and sediment accumulation and retention, in NOBOB ballast tanks, and to characterize source invertebrate populations and assess salinity toxicity as a barrier to prevent transfers of “high risk” species to the Great Lakes in ballast tanks.

Analysis of BMPs as a management tool to reduce the ANS risk on commercial vessels suggests that this approach is unlikely to provide a reliable, consistent protection against nonindigenous species introductions, but could result in some decrease in overall risk. Many of the recommendations put forth in Item 6, the main environmental precautionary practices of the Code, require information on local water quality conditions that is not generally available to the shipping industry, or are often not practicable on every voyage or with every ballast operation due to cargo loading and unloading requirements.  However, repeated and consistent application of ballast management practices can help to reduce sediment accumulations and associated populations of organisms and resting eggs, resulting in some risk reduction. 

Although not a complete barrier against all exotic species, salinity tolerance and on-board ballast water exchange experiments clearly showed that many invertebrate taxa that originate from low-salinity ports can be eradicated from ballast tanks relatively quickly through exposure to full-strength seawater (34 ppt).  This conclusion is especially true for species of rotifers, cladocerans, and copepods that are likely to occur in freshwater habitats (0-2 ppt).  Animals from habitats with higher average salinities (2-5 and 5-10 ppt) exhibited greater resistance to treatments of full-strength seawater, requiring longer exposure periods to kill them.  We recommend an exposure time of at least 24 hours, preferably more, to maximize mortality from saltwater exposure.  Typical ballast water exchange, required by law for ships carrying pumpable ballast water, would usually occur three or more days before ships enter the Great Lakes.   It should be emphasized, however, that saltwater exposure is unlikely to significantly reduce the risk from resting stages as a potential source of propagules.

Therefore, while BMPs, if consistently and repeatedly applied, can reduce the risk of introductions from NOBOB vessels by minimizing the amount of sediment and associated organisms that are transported within ballast tanks, the practical realities and limitations associated with vessel operations makes the existing BMPs inadequate as the lone strategy for reducing the risk of nonindigenous species introductions from NOBOB vessels.  On the other hand, experimental evidence suggests that the routine use of saltwater flushing as an official BMP for NOBOB tanks that have not otherwise been exposed to saltwater would greatly improve the protection framework for the Great Lakes, if aggressively implemented by the shipping industry, or required by regulations.

Our research results strongly support the implementation of new Canadian Ballast Management Regulations adopted in 2006 and the Policy Statement issued by The United States Coast Guard in 2005 requiring/recommending open-ocean tank flushing on NOBOB vessels entering the Great Lakes.  In order to reduce ANS risk, vessels operating outside the Great Lakes should conduct saltwater flushing of their empty (NOBOB) ballast tanks prior to each entry and as soon as possible after any subsequent ballast operations within the Lakes.  This recommendation would apply to both foreign vessels and coastal trade vessels that may operate from other fresh or brackish water ports within North American waters. 

For more information, contact
    Dr. David Reid, NOAA, 734-741-2019, david.reid@noaa.gov
    Dr. Tom Johengen, University of Michigan, 734-741-2203, Johengen@umich.edu

-- 
David F. Reid, Ph.D.
Director, NOAA National Center for Research on 
Aquatic Invasive Species (NCRAIS)
Senior Research Scientist, Nonindigenous Species Program
U.S. Department of Commerce
National Oceanic and Atmospheric Administration
Great Lakes Environmental Research Laboratory
2205 Commonwealth Blvd.
Ann Arbor, MI  48105-2945
Voice: 734-741-2019
FAX: 734-741-2055
GLERL home page:
    http://www.glerl.noaa.gov

-- 
David F. Reid, Ph.D.
Director, NOAA National Center for Research on 
Aquatic Invasive Species (NCRAIS)
Senior Research Scientist, Nonindigenous Species Program
U.S. Department of Commerce
National Oceanic and Atmospheric Administration
Great Lakes Environmental Research Laboratory
2205 Commonwealth Blvd.
Ann Arbor, MI  48105-2945
Voice: 734-741-2019
FAX: 734-741-2055
GLERL home page:
    http://www.glerl.noaa.gov
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