Aquatic Alien Invasive Species

Implement a Great Lakes Biologically Protective Standard

Science has shown conclusively that simply exchanging ballast water with highly saline water does not eliminate all aquatic alien invasive species, particularly those benthic ⁵ and dormant stages of species left behind in residual water and sediment in ballast tanks. Since mandatory ballast water exchange took effect in the Great Lakes over a decade ago (United States Coast Guard 1993), the rate of aquatic alien invasive species introductions has remained approximately the same. What has changed is the species composition, which has shifted to smaller open water forms such as zooplankton and phytoplankton. ⁶

In February 2004, after years of discussion, the International Maritime Organization adopted a convention on ballast water. While providing a hopeful step forward, it is not an immediate remedy. Ballast treatment standards would take effect for new ships in 2009 (assuming it is quickly ratified) and for existing vessels beginning in 2014, if enough nations ratify the treaty. Therefore, while not yet in effect, the Commission is pleased that the International Maritime Organization Convention has mandated that 95 percent of ballast water be exchanged, which would help ensures that all vessels reach the theoretical maximum efficiency of exchange.

The economic and ecological sustainability of the Great Lakes depends on having a much more effective biologically protective standard than that which ballast water exchange currently provides.

A Great Lakes biologically protective standard should:

• virtually eliminate the risk of introductions of aquatic alien invasive species



• kill or remove organisms of certain sizes or classes;



• reduce the threat of introducing pathogenic organisms; and



• ensure a standard that fully protects the freshwater Great Lakes environment, even if that standard exceeds the standard proposed through the International Maritime Organization Convention.

Because a large number of organisms could potentially be found in a ballast tank, sample analyses can be time-consuming and costly. The Commission agrees that analyzing a sample for a suite of certain indicator organisms is acceptable. This suite of indicators should include indicators of human pathogens like cholera at a minimum, as well as more traditional indicators of contamination by human or animal feces such as Escherichia coli or Enterococci. A standard that is biologically protective could lead to new technology to achieve the standard and new, rapid methods to measure effectiveness. In determining the standard, the Commission advises the Governments to ensure that economic analyses include the environmental and societal costs of invasive species (control, damage, mitigation, etc.), and the costs and benefits of prevention measures. This economic analysis applies equally and importantly to any navigation study proposed for the Great Lakes, such as the governments’ Great Lakes St. Lawrence Seaway Study.