Lake Trout Boreal FSI

The Fish Sustainability Index (FSI) uses scientific and local knowledge to assess the health of lake trout in Alberta's boreal forest.

Artist rendering of a lake trout

The Fish Sustainability Index (FSI) combines scientific, and local knowledge to assess the health of lake trout in the boreal forest of Alberta.

Lake Trout: Boreal FSI Maps

Adult Density (Current and Historic)

Stocked lake populations are denoted with a circle. Please note that data reliability is not currently displayed in these figures.

Habitat and Overharvest Protection Needs

Please note that data reliability is not currently displayed in these figures.

Lake trout FSI spatial layers can be viewed on our interactive web mapping platform.

Lake Trout: Boreal Population Status

In summary, lake trout in the boreal forest lakes of Alberta were found to have declined, but recent monitoring and improved regulations appear to be restoring degraded populations. Populations in the remote northeastern Canadian Shield area generally remain healthy.

Historically, lake trout were found in 17 lakes in the boreal forest zone of Alberta, outside of another 25 lakes in the Canadian Shield north of Lake Athabasca. Natural limitations of warm and shallow water likely limited some of these populations to a moderate abundance.

Two of the southern-most lake trout populations have been lost (Lesser Slave and Touchwood lakes), and Cold Lake fish were very nearly lost. None of the boreal forest populations remain at more than moderate abundance. Recent restrictive harvest regulations have begun to restore some of these fisheries, notably Cold Lake and Peerless Lake. The remote fisheries in the Canadian Shield appear to be maintaining moderate to high abundance.

Threats to Sustainability

The main threats to sustainability of lake trout in the boreal forest appear to be:

  • Heavy fishing pressure, including commercial fishing, appears to be a primary cause of the past declines. Improved road access and increasing sport fishing will continue to be concerns for lake trout sustainability.
  • Increasing summer temperatures will reduce available lake trout habitat. Extreme events (e.g., summer heat waves and droughts) may result in local summerkills.

Next Steps

  • Lake trout harvest must be carefully monitored and regulated to allow these fish to survive to their naturally old ages.
  • Population abundance should be increased, both to improve sport fishing quality, and to provide additional resilience to occasional summerkills.

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