A Canadian Action Plan to Address the Threat of Aquatic Invasive Species
Canadian Council of Fisheries and Aquaculture Ministers Aquatic Invasive Species Task Group

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Table of Contents


Scope of the problem

AIS are a large and growing problem in Canada, one that is compounded by a lack of knowledge and understanding about the issue. Since Canada is home to 20 per cent of the world's fresh water and has one of the world's longest coastlines, the economic and environmental consequences of inaction are extreme. Few people are sufficiently aware of the nature and magnitude of the threat and, as a result, there is a widespread lack of compliance with voluntary practices and regulations designed to limit the spread of AIS resulting from human activity. Although applicable legislation and regulations exist in many cases, they have not always been adequately brought to bear on the problem.

The consequences of invasive species becoming established include damage to sensitive ecosystems, as well as negative impacts on fishing, tourism, and other industries that form the backbone of local economies.

Sea lamprey are considered a significant factor in the collapse of the lake trout and whitefish fisheries in the mid-1940s and 50s. Prior to sea lamprey entering the Great Lakes, Canada and the US harvested close to 6.8 million kgs (15 million lbs) of lake trout in Lakes Huron and Superior each year. By the early 1960s the annual catch was about 136,077 kgs (300,000 lbs), a significant 98% decrease. The sea lamprey control program, implemented in 1955, has successfully resulted in reducing sea lamprey populations by 90%. The combined average annual investment by Canada and the US in the sea lamprey control program is $22 million. Although this program has led to increased employment and growth in commercial fish stocks, the ongoing expense underscores the fact that the cost of prevention is far less than the cost of control and mitigation. If sea lamprey had been prevented from entering Canadian waters in the early 20th century, these annual, continuing costs would never have materialised. The combined economic value (in Canada and the US) of recreational and commercial fishing on the Great Lakes is currently estimated at about $4.5 billion.

Examples of invasive species found in Coastal waters include the green crab and clubbed tunicate. The green crab affects East Coast native clams, mussels and oysters, and now also threatens West Coast shellfish. The invasive alga codium (oyster thief) threatens oysters in Atlantic Canada. In BC, the Japanese oyster drill caused significant damage to the oyster industry until it was brought under control in the mid-1900s. Even Arctic waters are affected, with the recent establishment of rainbow smelt in Hudson's Bay.

In addition to the primary effects, which can be seen shortly after a species becomes established, the alteration of such things as food webs and water quality can cause secondary impacts that take much longer to manifest. This further complicates governments' ability to manage invasive species. For example, the filter feeding activity of zebra mussels rapidly increased water clarity in the lower Great Lakes. Over a much longer period, the increased light penetration (due to clearer water) produced significant growth and spread of aquatic vegetation and increased the frequency and severity of toxic algal blooms.

Nearly twice as many invasions occurred during the second half of the 20th century (as compared to the first half) and recent data suggests that the pace is still accelerating. The increase in both the volume and speed of global trade, especially in the case of goods or vessels from countries with similar climates to Canada, has led to ever-higher risks of AIS entering Canada – risks that are further exacerbated by insufficient surveillance and enforcement.

The largest single source of new alien aquatic species, estimated at about 75 per cent in the Great Lakes region, is ballast water in ships. Water taken on in foreign ports, complete with local organisms, is discharged in Canadian waters, along with undesirable hitchhikers. Ballast tanks have been known to house up to several hundred different species. Globalization and internet-based commerce have also increased the intentional and unintentional importation of alien species for various purposes, some of which pose a threat if released into the wild. Not all invasive species come from overseas, some are native to North America but became harmful invasives because they were introduced beyond their natural range.

In February 2004, the International Maritime Organization adopted a Convention for the Control and Management of Ships' Ballast Water and Sediments. The Convention sets standards for acceptable numbers of organisms to be present in ballast water and establishes a timetable for compliance. It does not, however, include any provision for addressing the problem of vessels with no ballast on board, which are currently exempt from regulations. Ratification of the Convention will require the signature of 30 countries with 35 per cent of the world's shipping tonnage.

The number and intensity of calls to action have increased over the last decade, both within Canada and internationally. Domestically, these have come from sources such as the Standing Committee on Fisheries and Oceans and the Commissioner of the Environment and Sustainable Development. Other organizations, including the International Joint Commission, the Great Lakes Fishery Commission and various non-governmental organizations (NGOs) have also called for urgent action to deal with invasive species.

A variety of issues, priorities and jurisdictions

The consequences of AIS are often wide-spread and can touch on the environment, trade, shipping, recreational use of waterways, fishing, resource management, and human health. Efforts to resolve AIS problems are complicated and the solutions often involve trade-offs. For example, allowing a species to spread may irreversibly alter the ecosystem, thereby threatening fishing, recreation, and hospitality industries. However, efforts to stem its spread may require the use of toxic chemicals, hamper trade in certain commodities, or increase shipping costs. Management strategies must provide a thorough analysis of the potential risks and benefits of specific actions in order to balance environmental and economic interests.

Numerous jurisdictions and organizations are involved, from local to international levels. Within the federal government, primary responsibility and authority rests with Fisheries and Oceans Canada and Environment Canada but, depending on the species and its pathway into Canadian waters, management actions can also involve Transport Canada, Industry Canada, the Canadian Food Inspection Agency (CFIA), the Canadian Border Services Agency (CBSA), Health Canada and others. Provincial and territorial governments share the responsibility, as do bilateral organizations such as the International Joint Commission and the Great Lakes Fishery Commission. Industry, a variety of NGOs, Aboriginal peoples and the general public are also involved.

Many actions have been taken by governments and other stakeholders in response to the threat of invasive species. On the legislative front, many federal and provincial statutes exist to protect Canada's native biodiversity. Various organizations and jurisdictions have also initiated programs designed to educate specific groups about preventing the spread of invasive species. Coordination of these programs can be enhanced.

Not every part of the country experiences the same risk from AIS. The effects of specific pathways, and their associated risks, are greater in some regions than others. For example, the shipping pathway has resulted in the greatest number of established AIS in coastal provinces and those bordering the Great Lakes. The shipping pathway and ballast water management is the highest national priority for preventing new species from being introduced. Although the risk of introduction from the shipping pathway is less direct for Alberta and Saskatchewan, the spread of invasive species through recreational and commercial boating, inter- and intra-basin water transfers from neighbouring jurisdictions, and introductions from the aquarium trade are of greater concern. The flexibility to allow for regional and jurisdictional differences in priorities is an integral component of a Canadian AIS plan.

Efforts to coordinate laws and regulations with a bearing on aquatic invasive species are in their early stages. In many cases, broad regulatory mechanisms already exist to control the intentional and unintentional introduction of AIS but where resources will come from and who will bear enforcement responsibility needs to be addressed. In order to be effective, legislation and regulations must be coordinated within and between governments.

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