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Freshwater science

Learn about freshwater science at Fisheries and Oceans Canada (DFO) and what we do to control invasive species and preserve freshwater resources.

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About freshwater science

Conserving and protecting our natural resources must be based on an understanding of how we're affecting:

  • fish
  • fish habitat
  • aquatic ecosystems

Environmental science at DFO provides the scientific basis for the development of policy and regulations that help to protect Canada's vast freshwater resources.

Controlling invasive species

Our research into invasive species, such as sea lamprey, has helped protect Great Lakes salmonoid stocks, which refer to ray-finned fish like:

  • trout
  • chars
  • salmon
  • graylings
  • freshwater whitefishes

Sea lamprey is an invasive species that has threatened the Great Lakes for decades. Their aggressive feeding behaviour imposes biological stress on the native fish populations.

Research into the life cycle of sea lamprey led to the development of selective lampricides aimed at killing young lamprey. These lampricides have been successful in reducing sea lamprey populations in the Great Lakes.

We're now focusing our scientific effort on other methods of control, such as new biological controls and better physical barriers.

Preservation partners

We provide support for preserving our shared freshwater resources, such as:

  • strengthening and harmonizing agreements
  • sharing information, expertise and best practices

Our partners in this effort include the:

The International Joint Commission is an independent binational organization established by the Boundary Waters Treaty of 1909. It advises Canada and the U.S. on issues relating to the use and quality of boundary waters.

The Great Lakes Fishery Commission was established in 1955 by the Canadian/U.S. Convention on Great Lakes Fisheries. In addition to sea lamprey control, it also:

  • coordinates fisheries research
  • facilitates cooperative fishery management amongst various levels of the Canadian and the U.S. governments
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