This issue is in the early phases of development. The Blue Accounting AIS team is working with a diverse and binational group of experts from academic sectors and federal, state, and provincial governments to develop and refine the scope of this issue. The AIS work group is identifying the most relevant metrics to track progress toward preventing the introduction and spread of aquatic invasive species and controlling existing populations to reduce impacts in the Great Lakes basin.
The Great Lakes community is working together to:
- Prevent new introductions
- Establish regional surveillance programs and response capability
- Sustainably manage established species
The Great Lakes are one of the most heavily invaded freshwater systems in the world, with food webs dominated by non-native species that alter how the ecosystem functions, thus undermining efforts to improve water quality and restore native fish, wildlife and plant communities. Aquatic invasive species (AIS) also affect access to clean water for industrial and municipal users, interfere with recreation, and impact fisheries and tourism.
To sustain and restore the region’s freshwater resources and protect North America’s waterways, new invasions must be prevented and established AIS populations must be effectively managed. In the absence of comprehensive and consistent policies to reduce the threat of new invasions, and tools to reduce the damage from those species already introduced, the region remains vulnerable to impacts from new introductions and spread through human activities and natural dispersal.
Investments in AIS prevention and control are investments in thriving coastal industries, water quality, valuable ecosystem services and human health. Federal, state and provincial governments have identified the prevention and control of AIS as a Great Lakes priority worthy of inclusion in binational, state and provincial agreements (e.g., Great Lakes Water Quality Agreement 2012). There has also been substantial investment in AIS management within the Great Lakes community, though these efforts vary across jurisdictions and invasion pathways.
Blue Accounting supports collaborative approaches to AIS prevention and control by convening Great Lakes’ AIS experts and managers to establish metrics and track progress towards regional goals for managing AIS at each step in the invasion process. Blue Accounting enables Great Lakes leaders to easily understand the scope, progress and return on investment for AIS management, and informs future policy and management efforts.
Cleaning Zebra Mussels From Pump Room- Monroe Water supply was shut down by zebra mussels fouling the intake pipes. The economic impact on Great Lakes businesses and households is conservatively estimated to cost millions of dollars annually. The economic sectors most affected by AIS are sport and commercial fishing, tourism/recreation, water treatment, power generation, and industrial facilities that rely on Great Lakes water.
© Peter Yates/Getty Images
Alewife die off?
AIS such as sea lamprey and alewife (seen above on a beach dying in massive numbers due to overpopulation) have contributed to the decline and impeded recovery of valuable lake trout, whitefish and herring populations, as well as important native prey species. The impact of these species was so great that some native fish populations collapsed during the mid-20th century. In combination with the proliferation of zebra and quagga mussels, and later invaders such as the round goby, these AIS destabilize food webs, make food sources unpredictable, and bring instability to the Great Lakes commercial and sport fishing economies.
Sea lamprey feeding on salmonid fish
The top predator in the Great Lakes is the invasive sea lamprey. This eel-like creature attaches to large fish and sucks the life out of them. Sea lamprey contributed significantly to the decline of lake trout populations in the 1940s and 1950s. Today, the sea lamprey control program, costing $20 million per year, is the best global AIS control success story. The program uses a combination of traps, barriers, systematic monitoring, and selective lampricide treatments, and has successfully sustained a 90 percent reduction in lamprey abundance since the 1960s.
© M. Gaden/Great Lakes Fishery Commission
Ocean-going ship in the Great Lakes
The adoption of effective polices aimed at pathways of invasive species movement, like ballast water, is contributing to a reduction in the number of new species introduced to the Great Lakes. Prior to 2007, new species were being discovered at an average rate of one every eight months. The rate appears to have slowed over the last decade, in part due to new requirements that ships exchange or treat their ballast water prior to entering the Great Lakes.
©Comité sectoriel de main-d’œuvre de l'industrie maritime
Asian carp jumping
Despite considerable progress over the last several decades, the region remains under threat from a suite of invaders like silver, bighead and black carp, northern snakehead, and numerous invasive plants. These new threats provide the impetus for further innovation and strengthening prevention policies. Today, the Great Lakes region is leading the development of new technology to more effectively detect species, prevent their spread, and reduce their abundance.
©T.Lawrence/Great Lakes Fishery Commission
The Great Lakes community is served by many groups working to advance effective and coordinated approaches to AIS prevention and control. This includes 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, among others. The Blue Accounting AIS work group includes members of these groups and other experts involved in preventing and controlling AIS in the basin.
Keys To Success
Managers, researchers, and stakeholders across the Great Lakes region are undertaking efforts to prevent and control AIS. These efforts reduce the likelihood that AIS are introduced and spread, manage existing populations of AIS, and minimize AIS impacts when they occur. Universities, private industries and other nongovernmental organizations support and contribute to AIS management efforts, helping to increase their effectiveness and likelihood of success. The numerous entities involved in AIS management work together in the following ways:
- Investment in scientific tools and information: Advancing our understanding of the way AIS move into and around the region, establish populations, and impact our economy and ecosystems is necessary to ensuring the most effective polices and approaches are implemented to stop them. Additional investments to develop the technology and methods to determine which species pose the highest risk to our region; detect species as they are moving into or around the region; and reduce or remove populations once they are here, are needed to further strengthen management efforts.
- Policy development, refinement and implementation: Consistent policies designed to prevent new invasive species from entering the Great Lakes region, and prevent the spread of species already here, are needed at the state, provincial and federal level. Gaps in policy, compliance and enforcement leave the region vulnerable to new invasions.
- Participation in multijurisdictional efforts: Binational and interstate agreements and working groups are important to helping harmonize state, provincial and federal AIS policies and management, as well as providing mechanisms for sharing resources, technical knowledge and lessons learned. The effectiveness of AIS management efforts is only increased when jurisdictions work together to stop species that don't respect jurisdictional boundaries.
An Ounce of Prevention is Worth a Pound of Cure
AIS management efforts may be targeted at specific species or invasion pathways. For example, the longstanding program to control the invasive sea lamprey costs more than $20 million annually, illustrating how prevention is less costly than the on-going efforts to control established AIS. Recognizing this, many agencies are now working to prevent the introduction of invasive silver and bighead carp into the Great Lakes region and are implementing an Asian Carp Action Plan to coordinate their efforts.
Given the high cost of controlling a single species, it is often more effective to target prevention efforts at the key pathways that can introduce and spread potential AIS. There are several primary pathways through which non-native species are moved and spread to new areas and habitats. Historically, the most significant pathway of introduction of non-native species to the Great Lakes region is the ballast water of ocean-going ships. However, over the last 25 years a comprehensive regulatory program for ballast water has been implemented which has significantly reduced the number of new species introductions associated with ballast water. Other pathways of concern include the trade of live organisms, recreational boating, and man-made canals that artificially connect the Great Lakes region to other major watersheds like the Mississippi River.
Where We Work
Trailered boats and vehicles, as well as other watercraft and associated equipment are an important contributor to spread of AIS. AIS can hitchhike on watercraft and have the potential to move between water bodies when these boats, trailers and other equipment are not cleaned thoroughly. AIS can be present in mud or water, attached to hulls, or wrapped around motors or trailers. Many AIS can also survive short overland movement and may be released when the boat and/or vehicle is launched into a new water body.
©Photo by Wisconsin Sea Grant
Trade in Live Organisms
Trade in live organisms includes the growing and sale of aquatic plant and animal species, and includes aquaculture facilities, the aquarium pet and plant trade, live bait sales, biological supply companies, legal stocking, live food, horticulture, and water gardening. Transactions may take place online via e-commerce, or through brick-and-mortar retailers. The movement of live organisms through trade greatly expands the geographic scope of where invasive species may be spread, as online orders may be shipped all over the world. Once purchased, organisms may be released, either intentionally or unintentionally, into a body of water.
© Photo by Wisconsin Sea Grant
Canals and Waterways
Canals and Waterways
The passage of invasive species into, around, or out of the Great Lakes is facilitated by connections between water bodies, both natural and man-made. Man-made canals, including the Erie Canal and the Chicago Sanitary and Ship Canal, artificially connect the Great Lakes to the Hudson and Mississippi Rivers allowing the two-way flow of species between these major watersheds. Barriers to natural dispersal like dams, culvert and road crossings can prevent the upstream movement of organisms, but efforts to restore native fish passage may also open previously uninvaded waters to invasive species colonization.
© William "Lindsay" Chadderton/The Nature Conservancy
Shipping activities may move invasive species through a ship’s ballast water discharge or via hull fouling. Depending on the amount of cargo on board, ballast water is often taken on board or discharged to stabilize the vessel. Ballast water taken up from one port, or during a voyage, may be transported and discharged in another port or geographic region. This water often contains live organisms that can survive passage and be discharged along with the ballast water into areas where they are not native. Likewise, organisms may attach directly to the hull of a boat, known as hull fouling, and be moved between ports in this manner.
© Photo by Michigan Sea Grant