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Mountain Whitefish
Prosopium williamsoni

Also known as Rocky Mountain whitefish, they are sometimes mistaken for grayling.

What do Mountain whitefish look like? Mountain whitefish look quite a lot like trout, but they have a much smaller head, a larger adipose fin, larger scales and no teeth. Their snout is pointy and sticks out past their mouth. Whitefish are grayish to light brown on the back, silvery on the sides and white on the belly. They have relatively large scales that are round and may be outlined with black.

Food for Thought... Whitefish are hard to catch - they don't often stay on the fisherman's hook. What feature of their anatomy makes this happen?

Where do they live? Mountain whitefish are only found in western North America from the Yukon/BC border to Nevada. They are not found along the coast or further east than central Alberta. They live in both lakes and streams.

What is their life cycle like? The mountain whitefish usually spawns for the first time between three and four years of age. These fish spawn in the winter - between October and February over gravel or rocks in steams or in shallows along a lakeshore. They do not build nests - and they only spawn after dark! The eggs hatch in early spring.

Did you know that … Mountain whitefish can live up to 17 or 18 years. One was caught in Alberta that was actually 29 years old.

Food for Thought... What feature does a whitefish not have that makes it distinctive from the Grayling?

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