Freshwater

Mountain whitefish

Pescado blanco de montaña

Prosopium williamsoni

Freshwater

At a glance

Typical size

10–16 in.

Depth

3–15 ft.

Best time

Midday in winter.

Found in

5 areas

Spot it, size it up and learn its habits.

Identification: Slim, round, silvery fish with large scales, a small mouth under a short, pointed snout, an adipose fin like a trout, and a forked tail.
Typical size: 10–16 in.
Maximum size: About 20 in and 5 lb.
Diet: Aquatic insects, especially nymphs.
Behavior: Schools in deep runs and pools; bites well in winter when trout are slow.

Where, when and how deep to look.

Where to find it: Found from Rocky Mountain Trout Rivers, Pacific Northwest Rivers & Lakes, British Columbia, Canadian Prairies and Yukon, NWT & Nunavut. Cold rivers and lakes of the Rocky Mountains, the Columbia basin, British Columbia, Alberta and the Yukon.
Habitat: Cold rivers and lakes of the Rocky Mountains, the Columbia basin, British Columbia, Alberta and the Yukon.
Depth: 3–15 ft.
Fishing depth: Deep runs and pools.
Best season: All year; winter is a classic time.
Best time: Midday in winter.
Best tides: No tide — in rivers, falling water after the rainy season is best.
Best weather / conditions: Calm winter days.

What to tie on and what to throw.

The rod, reel, line and lures BigJoe would use.

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Step by step, from first cast to landing.

Go where it lives: Cold rivers and lakes of the Rocky Mountains, the Columbia basin, British Columbia, Alberta and the Yukon.
Rig up: Light fly rod or ultralight spinning rod. 5X tippet.
Pick your bait: Maggots and small worms where allowed. Lures: Small nymphs and beadhead flies.
Fish it: Nymph deep runs with small flies under an indicator.
Time it: Midday in winter. No tide — in rivers, falling water after the rainy season is best.

Fishing techniques: Nymph deep runs with small flies under an indicator.
BigJoe's tip: A great winter fish when trout fishing is slow.
Catch and release: Catch and release: wet your hands, keep the fish in the water when you can, and release it quickly. Use circle hooks and a dehooker.

Is it good to eat, and how to prepare it.

Edibility: Good eating when fresh.
Cleaning: Bleed and ice it right away. Fillet, then remove the skin and any dark bloodline.
Cooking suggestions: Mild white meat; excellent smoked.

Safety, rules and taking care of the fishery.

Safety warnings: Icy banks and cold water in winter.
Regulations: Usually liberal limits; some waters have winter whitefish-only seasons. Licenses, limits and seasons are set by each province, territory or state, and many lakes and rivers have special size limits, slot limits or closed spawning seasons — check the current regulations for the water you fish.
Conservation: Native and common.

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Sources & photo credits