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Lake Trout

Lake Trout

Lake Trout (Salvelinus namaycush) are actually chars, not true trout, belonging to the same genus as Bull Trout and Brook Trout.

Known as 'mackinaw' or 'namaycush' (meaning 'dwellers of the deep'), they're the largest freshwater salmonid native to North America.

Scientific Name: Salvelinus namaycush

Also known as mackinaw, namaycush

Physical Characteristics:
  • In Montana, they're distinguished by their deeply forked tail, light spotting on a dark background ranging from light green to almost black, and white anterior borders on their pectoral, pelvic, and anal fins.
  • Montana's state record is a 42-pound fish from Flathead Lake.

What to know

Habitat Distribution

  • Native populations in Montana are found in only a few locations: the St.
  • Mary and Missouri River drainages.
  • These represent remnant populations from Pleistocene glacial refugia.
  • Lake Trout have also been introduced to Flathead Lake, Fort Peck Reservoir, and scattered mountain lakes.
  • They inhabit very deep, cold lakes.

Key Locations

  • Flathead Lake (Woods Bay, Yellow Bay, Blue Bay, West Shore State Park, Conrad Point, Painted Rocks/Cedar Island, Wildhorse Island, the Narrows, Finley Point, and Gravel Bay), Fort Peck Reservoir, Waterton Lake, Glenns Lake, Cosley Lake, St.
  • Mary Lake in Glacier National Park, Lower St.
  • Mary Lake on the Blackfeet Indian Reservation, Twin Lake in the Big Hole River drainage, and Elk Lake in the Red Rock River drainage.

Specific Spots

  • Rocky substrates, steep shorelines with rocky substrates for shore fishing.
  • Spawning occurs over rocky substrate in depths from 10-120 feet.

Lake Trout FAQ

Answers from onWater's species guide.

What are the best lures and bait for Lake Trout in Montana?

Leadhead jigs with 3-5 inch plastic grub bodies in white, chartreuse, or glow-in-the-dark colors, tipped with cut fish. Use 1/2 to 2 oz jigheads depending on depth. 3/8 oz spoons (Krocodiles in silver/red or gold/red) or minnow plugs (Rebels, Rapalas in black/silver or fluorescent orange).

When is the best time to fish for Lake Trout in Montana?

Shore fishing is possible in May-June and October-November when water is cool. Spring and fall when surface temperatures are within their preferred range.

How do you catch Lake Trout in Montana?

Vertical jigging is highly effective, jigging 1-3 feet off bottom every 10-20 seconds. Trolling methods include flatlining 100-200 feet behind the boat in 30-200 feet of water. Downriggers using squid and dodger combinations - place squid 2.5 dodger lengths behind an 8+ inch dodger.

What do Lake Trout eat?

Young Lake Trout feed on plankton and aquatic invertebrates, but fish over 2-3 pounds become primarily piscivorous, eating other fish.

Where do Lake Trout live in Montana?

Native populations in Montana are found in only a few locations: the St. Mary and Missouri River drainages. These represent remnant populations from Pleistocene glacial refugia. Lake Trout have also been introduced to Flathead Lake, Fort Peck Reservoir, and scattered mountain lakes. They inhabit very deep, cold lakes.

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