Bull Trout (Southcoast British Columbia populations)

Salvelinus confluentus

SARA Status
No Status
NS
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

SARA Status

  • No Status NS
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX
COSEWIC Status
Not at Risk
NR
Special Concern
SC
Threatened
TH
Endangered
EN
Extirpated
EX

COSEWIC Status

  • Not at Risk NR
  • Special Concern SC
  • Threatened TH
  • Endangered EN
  • Extirpated EX

Description

Bull Trout (Salvelinus confluentus) are widely distributed throughout North America. The species' name is derived from its large broad head and prominent upper jaw. Bull Trout have a long and slender body. They are olive-green to blue-grey in colour with a pale belly. The belly may turn yellow, orange or red in spawning male Bull Trout. The pale round spots that speckle their sides and backs make it easy to distinguish a Bull Trout from most other salmonid species.

Bull Trout can occur in four different life history forms: stream resident, fluvial (move from stream to larger rivers for juvenile rearing), adfluvial (mature in lakes but migrate up streams to spawn) and anadromous. The first three forms are common throughout the Canadian range. Restricted to the southwestern portion of British Columbia, the South Coast British Columbia population represents the only anadromous life history type in Canada.  

Habitat

The Bull Trout is a cold-water species found in lakes, streams and rivers and in the case of South Coast British Columbia population, can be found in the Pacific Ocean. The anadromous form migrates from natal freshwater streams to feeding habitat at sea. The South Coast British Columbia Bull Trout populations reside in five large river systems: Skagit River, Squamish River, Lillooet River, Lower Fraser River and Lower Fraser Canyon.

Preferred spawning areas are usually cold, clean, and small flowing streams with cobble or loose gravel bottom. Cover is extremely important to all life history stages. Bull Trout tend to hide by staying near substrate, submerged wood or undercut banks. Fry tend to be found in shallow side channels, while rearing juveniles prefer pool habitats. Most Bull Trout overwinter in deeper pools to avoid interactions with ice.

Threats

A number of factors combine to limit the abundance of Bull Trout in Canada. The species' specific habitat requirements, late maturity and low reproductive potential render the species vulnerable to change. Currently, habitat degradation and fragmentation, introduced species, and overexploitation are the primary threats to South Coast British Columbia Bull Trout populations.  Land use practices, such as oil and gas development, forestry, mining, agriculture, transportation infrastructure and hydroelectric projects, degrade and fragment freshwater habitat. These practices can disrupt migration, decrease woody debris, modify river systems, increase water temperature, and increase siltation. Warming and changes in river flow caused by climate change will also likely negatively influence Bull Trout habitat.

Expansions of introduced species also pose a significant threat to Bull Trout. For example, the non-native Brook Trout is cause for serious concern. This species is known to displace Bull Trout, compete for resources and space, and reduce the reproductive capacity of Bull Trout by interbreeding.

The species is threatened by overfishing through angler mortality and poaching. The species is particularly vulnerable to overharvesting because it can easily be caught in low densities with little angling effort. Incidental by-catch mortality from commercial and recreational Pacific salmon fisheries also threatens the species. Anadromous South Coast British Columbia Bull Trout populations make multiple migrations between freshwater and saltwater and can get captured in these fisheries.

Further Information

Provincial and territorial authorities license anglers and angling guides, and regulate scientific fish collection permits. Through regulation, the species receives some protection in British Columbia. Regulations incorporate a variety of measures to protect fish stocks. These include stream and lake closures, catch and release fisheries, size and catch limits, and gear restrictions. Bull Trout is also one of four fish listed under the Identified Wildlife Management Strategy of the Forest and Range Practices Code of British Columbia. This recommends special management attention for such species under the Forest and Range Practices Act.

This species is under consideration for listing as Special Concern under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available on the Species at Risk Public Registry.

To find out further information about how this species is protected by provincial or territorial laws, consult the provinces' and territories' website.

Bull Trout (Southcoast British Columbia populations)

Illustration of a Bull Trout (Illustration © Joseph R. Tomelleri)

Illustration © Joseph R. Tomelleri

Scientific name: Salvelinus confluentus
SARA Status : Under Consideration
COSEWIC Status : Special Concern (November 2012)
Region : British Columbia

Bull trout

Photo credit: Fisheries and Oceans Canada

Region map

Region map, British Columbia

Did You Know?

Bull Trout will eat just about anything they can fit in their mouth. Some individuals have even been known to prey on ducklings!

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