Science for freshwater fish habitat management in Canada: Current status and future prospects

Abstract

Canada's diverse freshwaters support a rich biodiversity of more than 200 species. Canada has strong legislation capable of conserving and protecting freshwaters habitats. Fish are a key driver and indicator for restoration and conservation efforts. Many of Canada's freshwater species in Canada are thought to be at risk.

Apart species such as brook trout, lake trout, walleye, and yellow perch, the ecology and habitat requirements of most freshwater species are poorly known. Studies have mainly been descriptive and comparative but experimental, ecosystem-scale integration, and modelling activities are increasing. While science related to fish and their habitats is growing, little is focused on the links between the production and dynamics of fish populations and communities, and the supply and distribution of habitats at various scales.

Habitat management is still mainly reactive, assessing development at the site-level with considerable uncertainty about the mitigation and compensation actions approved to offset habitat losses and modifications. Communication between science and management is improving. Canada has invested much energy on cumulative impact assessment but effective methods for tracking cumulative change and the interaction of multiple stresses have not emerged. Nonetheless there is a broad consensus on the need to take an ecosystem-based approach to sustainable use of Canada's natural renewable resources, including freshwaters and their fish. Management needs to shift to a more proactive approach supported by better deployment of available science and scientific methods. Science should emphasize quantitative whole ecosystem studies of fish and habitat especially the development of models and experimental manipulations.

If current trends of fish habitat loss are maintained in Canada, further declines in the quality and diversity of freshwater fish resources are certain despite our apparent natural wealth. Modest investments in securing the future of its freshwater fishery resources based on scientific advice may yet begin movement toward an ecologically sustainable future.