Species

Westslope cutthroat troutOncorhynchus lewisi

A cold-water trout of the Rocky Mountain headwaters, named for the red slash beneath its jaw and recognisable one by one from its spots.

Photo: Marcus Ganahl / Unsplash

The westslope cutthroat trout lives in cold, clean headwater lakes and streams of the upper Missouri and Columbia basins, in British Columbia, Alberta, Montana and Idaho.1 It takes its name from the red, pink or orange mark beneath the jaw, which also tells it apart from rainbow trout.1

A westslope cutthroat trout: golden body, black spots and the red slash beneath the jaw

Under pressure

Genetically pure westslope cutthroat trout now survive in less than 3% of their historic range.1 Introduced rainbow trout interbreed with them, logging and dams degrade their streams, and invasive lake trout and kokanee compete for food.1 The species is considered threatened in its native range in Alberta.1

What we do

Every cutthroat carries its own pattern of black spots. In the Elk River, British Columbia, our trout identification work matches those patterns between photos, so biologists can recognise a fish they have met before without tagging it.

Two photos of the same trout with matching spots joined by green lines

Trout Identification

Trout Identification

Non-invasive technology for monitoring trout populations using computer vision to accurately identify individual fish.

Trout Identification

Trout Identification

Reading the spot patterns on trout to identify individual fish, a non-invasive way to monitor populations.

Animal reID

A modular computer vision framework for individual animal identification using state-of-the-art techniques including metric learning, local feature matching, and spot pattern analysis across multiple species.

Open to collaboration

Every project here was built hand in hand with conservation partners, and much of the code is open source. If our work fits a challenge you're facing, or you'd like to build something together, we'd love to hear from you.