Description
Appearance
- Bull trout are long, slim fish with a large head in proportion to the body.
- Back is olive-green to grey while sides are silvery and marked with pale yellow to red spots.
- There are no black spots on the dorsal fin.
Distribution
- The official fish of Alberta, bull trout are native trout with the largest natural distribution of all trout in the province.
- This species is found in all river systems with headwaters in the mountains.
Natural History
Habitat
- Bull trout are usually found in pools or backwater areas, instead of fast-moving riffles and rapids.
Food
- Bull trout prey on other fishes, especially mountain whitefish.
- Diet can also include:
- aquatic invertebrates
- crustaceans
- molluscs
- insects floating on the water's surface
Reproduction and Growth
Breeding Behaviour
- Bull trout spawn in the early fall in small creeks.
- Females dig large redds (nests) in gravel and cover the fertilized eggs.
- Eggs hatch in March or April.
Growth Process
- Bull trout grow slowly in their preferred cold-water areas, and spawn at around five years old, later than other trout species.
Conservation and Management
Status
Bull trout are classified as Sensitive in the current General Status of Alberta Wild Species report. See:
Bull trout are also classified as Threatened under Alberta's Wildlife Act; protective regulations under this Act that apply to fish species are under development. See information on Species at Risk at:
Issues
- The spawning fish are usually quite large, over 30 centimetres (12 inches), and are very vulnerable to capture by bears, ospreys and people.
- Over-harvesting of this species has led to a decline in population. Protection from angling may result in recovery, but that may be countered by habitat degradation, and competition from introduced species.
Current management
Fish Sustainability Index
Alberta's bull trout populations have been assessed under the Fish Sustainability Index, see:
Fishing
Bull trout are cold-water game fish subject to current Alberta sportfishing regulations.
Because of the bull trout's vulnerability, Alberta Sustainable Resource Development (SRD) has implemented a zero possession limit on this fish throughout the province. All bull trout that are caught must be released. For details, see the My Wild Alberta website at: