Aquatic invasive species cost Great Lakes communities and businesses millions of dollars each year.

Our Goal

  • Prevent the introduction of new aquatic invasive species
  • Detect and respond to new introductions of aquatic invasive species
  • Control established aquatic invasive species to reduce impacts

Protecting the Great Lakes

The Great Lakes basin is among the most heavily invaded freshwater systems in the world. Its food webs are dominated by invasive species that change how the ecosystem functions and result in substantial economic costs to the region: limiting access to clean water, interfering with recreation, disrupting fisheries and hurting tourism.

Public and private stakeholders recognize that effective Aquatic Invasive Species (AIS) prevention and control is needed to restore thriving coastal industries, water quality, valuable ecosystem services, and human health. Federal, state and provincial agencies are making meaningful binational commitments and substantial investments to protect our Great Lakes from harmful AIS. Advised by agency representatives and other partners, Blue Accounting is tracking progress towards the development and implementation of a comprehensive regional AIS management program.

Why It Matters- Making a difference

Why It Matters

Zebra Mussels

Zebra mussels and other AIS can have big economic impacts. In Monroe, Michigan, the water supply was shut down by zebra mussels clogging the intake pipes (pump room clean out pictured above). Removing invasive mussels from a single water treatment plant can carry substantial cost. The economic impact of AIS on Great Lakes businesses and households is conservatively estimated to cost millions of dollars annually.

© Peter Yates/Getty Images


Alewife contribute to loss of native species

AIS such as sea lamprey and alewife (seen above dying in large numbers due to overpopulation) have contributed to reduced lake trout, whitefish, herring and prey species populations. During the mid-20th century, the impact was so great that some native fish populations collapsed. In combination with other invaders like zebra mussels, quagga mussels, and the round goby, these AIS make food sources unpredictable for native species, which brings instability to commercial and sport fishing economies in the Great Lakes.

©Bettmann/Getty Images

Sea lamprey feeding on salmonid fish

starry stonewort blocking diver's path in lake

AIS can interfere with our ability to enjoy the Great Lakes. Starry Stonewort, for example, is an invasive plant that grows densely and prolifically. In addition to harming native organisms, it can grow so thick that boating, fishing, and swimming are nearly impossible.

© William "Lindsay" Chadderton/The Nature Conservancy

Who's Involved

The Great Lakes community is served by many forums working to advance AIS prevention and control including the Great Lakes Panel on Aquatic Nuisance Species, Great Lakes Water Quality Agreement Annex 6 Subcommittee, Great Lakes St. Lawrence Governors & Premiers AIS Task Force, Great Lakes Fishery Commission, and the International Joint Commission. We have convened a Blue Accounting AIS work group comprised of regional AIS experts who are members of these forums. While the content on Blue Accounting does not necessarily reflect the views of any individual work group member or organization, this collaborative approach aims to create a product of their collective expertise .

How We Work

Blue Accounting is working to support efforts to advance effective and coordinated approaches to aquatic invasive species (AIS) management across the Great Lakes region. Working across the invasion process (below), the Blue Accounting AIS work group is collaborating to identify strategies and track progress toward regional AIS goals. The work group is prioritizing management strategies within Prevention, Detection and Response, and Control of Established AIS and  Blue Accounting is synthesizing existing data and information to:

  • Track progress toward regional goals
  • Provide context on strategies and investments deployed to reach those goals
  • Deliver reliable regional information to inform AIS stakeholder
Making a Difference

Making a Difference


cargo ship on the detroit river
<div class="text-formatted field field--name-field-media-tooltip field--type-text-long field--label-hidden field__item"><p>© Photo by Michigan Sea Grant</p></div>


Well-targeted prevention policies help reduce the number of new species entering the Great Lakes. Prior to 2007, a new species was discovered in the Great Lakes every eight months on average. That rate has dropped in the last decade since new rules were introduced requiring ships to exchange or treat their ballast water before entering the Great Lakes. Other targeted prevention strategies have the potential for similar impacts.

© Photo by Michigan Sea Grant



Despite considerable progress over the last several decades, the Great Lakes remain under threat from a suite of invaders including invasive fish like the silver carp (pictured here). Today, the Great Lakes region is leading the development of new technology to more effectively detect species early in the invasion process, which increases the chances of successful detection and eradication of new invaders.

© T. Lawrence/Great Lakes Fishery Commission



The sea lamprey, an invasive eel-like creature, is now the top predator in the Great Lakes.  Established invasive species can have a huge impact on Great Lakes ecosystems. Programs such as the sea lamprey control program can have enormous impacts on reducing the presence of an invasive species, in turn, protecting critical resources and industries. 

© M. Gaden/Great Lakes Fishery Commission

Measuring Progress

Blue Accounting is developing metrics for tracking shared goals to better understand the scope, progress and return on investment for AIS management in the Great Lakes. These metrics will be refined over time, as our understanding of strategies and investments evolves.

Preventing the introduction of new non-native species is the most cost-effective approach to minimize future threats from AIS. Prevention activities aim to reduce the risk of uptake, movement and introduction of non-native species, and may be applied to any of the pathways that introduce AIS into the Great Lakes basin: trade in live organisms, recreational activities, shipping, and canals and waterways.

Early detection (i.e., monitoring) and response programs are intended to detect introductions of new non-native species early while populations are still localized. Early detection increases the likelihood that response efforts to contain, control, and ideally eradicate new populations will be effective. A comprehensive basin-wide approach is needed to coordinate and guide detection and response efforts. 

More than 185 non-native species are established in the Great Lakes, a proportion of which are considered invasive and are causing ecological and/or economic damage. While significant progress is being made to prevent the introduction and establishment of new AIS, damaging populations of AIS that already exist should be managed to reduce their negative impacts. 

Where We Work

Geographic Boundaries

Lakes and Streams

Great Lakes and streams to first barrier

The Great Lakes, connecting channels, and Great Lakes tributaries up to the first barrier form  one large interconnected water body with no barriers to prevent natural dispersal throughout the entire system. 


Great Lakes Basin

The Great Lakes and associated watersheds form one large catchment area. There are no natural barriers to prevent AIS introduced into the headwaters of any Great Lakes tributary catchment from spreading downstream into the Great Lakes.

GL States

Great Lakes States and provinces

Management of aquatic invasive species is driven primarily by state, provincial or federal management agencies, and regulations often apply to all waters within these jurisdictional boundaries.