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Flathead Lake Fish

What Kind of Fish Are In Flathead Lake?

Beautiful Flathead Lake is crystal clear, 15 miles wide, 28 miles long, 120,320 acres and 370+ feet deep with 168 miles of shoreline. Fed by the drainages of the Rocky Mountains and Glacier National Park, Flathead Lake is the largest natural lake west of the Mississippi. Surrounded by woods and beautiful estates, it is the home to osprey, eagles and abundant wildlife. Flathead Lake itself is full of Lake Trout (Mackinaw) Mackinaws thrive in the cold, clear, well oxygenated water of Flathead Lake.

The Lake features a mostly rocky gravel bottom and ideal water temperatures. Along with the ample food supply available, this provides the perfect environment for Lake Trout. With an average catch length of 22″-26″. Lake Trout have been caught measuring over 40 inches! The record fish weighed 42 pounds and measured 42″.

These Native fish can be found in this large body of water. Bull trout, Westslope cutthroat trout, Mountain whitefish,  Pygmy whitefish, Largescale sucker,  Northern pikeminnow, Peamouth chub, Redside shiner,  Slimy sculpin,  Longnose dace, 

There are over 25 fish species found in the Flathead River-Lake ecosystem. The primary sport fish that we target for catching are below.

Lake Trout

Long-lived, slow growth, deep-dwelling, photophobic, voracious feeder. The main sport fish in Flathead and the apex predator. This trout is quite a catch. Learn!

a man holding a fish in the water

Rainbow Trout (also Kamloop)

Aerial acrobat. Good stamina. Topwater feeder. I hope you’re ready because this Trout will scream a reel and put up a fight! With a small amount of color on the face, underbody and fin, this trout takes the cake for the best-looking fish in Koocanusa. Will you catch one? Learn more here!

A man holding a rainbow fish

Bull Trout

Powerful fighter and available for harvest  (1 only) with a catch card (available regionally at Fish Wildlife and Parks). Learn more here!

a man and a girl holding a fish

Lake Whitefish

The bulldog. Small head and solid muscle. Vigorous fight and unbelievable stamina. Soft mouth. Many tear free from the hook. These are hard fighting fish with big numbers, white and mild-tasting meat. They average about 2 1/2 lbs but can run over five lbs. We have landed 100 of these in a single charter! Learn!

A girl holding a fish

Misc. Flathead Lake Fish Info:

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish, Wildlife and Parks (MFWP) cooperatively manage Flathead Lake under the Flathead Lake and River Fisheries Co-management Plan.

Lake trout up to five pounds eat lots of Mysis shrimp and can be delicious fried, baked, barbecued, or smoked. Fish from 5-10 pounds are much oilier and are best put back to grow to trophy size. Macs over 10 pounds are mostly for fun and over 20 pounds should ONLY be considered for your wall!