Great Lakes Health: Non-native Species

Courtesy of

Preventing the introduction and spread of non-native species in the Great Lakes is a
major concern in this region. Currently, the Great Lakes have 185 KNOWN non-native species.
Of these non-natives, some are considered invasive species, or species that cause economic and
ecological harm to an ecosystem. This is an area of particular concern because of the far reaching implications regarding water quality, industry and biodiversity.

Ballast water* is major vector in the introduction of non-native species into the Great
Lake and a compromise between industry and the environment is often needed. Exchanging
ballast water while underway can be very dangerous, depending on the conditions at sea, and
also costs the company money because it takes time.

The Nonindigenous Aquatic Nuisance Prevention and Control Act (NANPCA) of 1990
was an inter-agency, federal program that was intended to identify and implement was to prevent
the unintentional introduction and spread of invasive species into waters of the US, to work
towards minimizing economic and ecological impacts of already established non-native species,
and to establish a program to assist states in the management of such species. In 1996, the
National Invasive Species Act (NISA) amended the NANPCA and including findings regarding
the unintentional transportation of non-natives through recreational and commercial vessels.
The act not only mandated regulations to prevent the spread of non-native species into the Great
Lakes through ballast water, but also required such programs to demonstrate technologies and
practices that prevented the introduction of non-native species as well.

Courtesy of NOAA

In March of 2012, the United States Coast Guard (USCG) published a final rule
that further regulates the discharge of ballast water into US seas. This final rule applies to sea-
going vessels and coastwise vessels that do not operate outside the EEZ, known as the exclusive
economic zone**. Vessels that depart from the Great Lakes and transit beyond the EEZ, and
return upstream of the Snell Lock are also regulated by this final rule. The rule expands on the
existing acts by expanding on the previous management plan. Training and safety procedures
regarding fouling, sediment removal must be updated. However some parts of the rule remained
the same. Vessels must avoid taking up or discharging in sensitive areas or areas with
infestation. Tanks must be cleaned and anchors and chains must be rinsed. The discharge
standard in the final rule was not updated, despite the 2009 “phase-two” standard that was 1000
times more stringent. The discharge standard requires fewer than 10 organisms per cubic meter
for organisms greater than or equal to 50 micrometers (0.005 centimeters) and fewer than 10
organisms per milliliter for organisms between 10 and 50 micrometers (0.001 and 0.005

In order to meet the discharge standard, vessels have different systems that can be

  • A USCG balast water system
  • Water from a public water supply
  • An alternate management system, approved by a foreign entity as well as the USCG
  • Retain ballast water on board while in US waters, or
  • Discharging to a reception facility

The ballast water exchange regulations will continue to be in existence and will continue to receive input from all sides, encouraging or discouraging its continued use. However, as long as we have a globalized economy, the introduction of species into new areas will continue to be a threat, how we manage it is what will change.
*Ballast is a substance, typically water that is stored in compartments and holds of vessels that
increase stability and maneuverability.

** The EEZ a sea zone over which a state has special rights over the exploration and use of
marine resources. It stretches from the seaward edge of the state’s territorial sea out to 200
nautical miles from its coast.


A great graphic of the spread of zebra mussels:

Emily Shaw, Contributing Writer

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