Giant Mackinaw trout live in deep water, are rarely seen except on an angler’s hook

Editor’s note: The 2017 Idaho Outdoors fishing guide cover story was on some of the biggest, baddest fish in Idaho — and the anglers who pursue them. Here is the column introducing the series.

Today: Mackinaw trout

Previously: Tiger muskies

Coming up: Chinook salmon (Monday), flathead catfish (Wednesday) and white sturgeon (March 16).

MACKINAW TROUT

Where to catch them: Payette Lake, Warm Lake, Stanley Lake.

Recommended gear: Medium-heavy action rod and a large bait-casting or spinning reel spooled with at least 200 yards of 10- to 20-pound line.

What to use: Trolling rigs with large flatfish and Rapalas (summer), large spoons, swimbaits and tube jigs (winter).

State record: 57.5 pounds, caught by Lyle McClure in 1971.

Catch-and-release record: 39.5 inches, caught by Tom Henson in 2017.

Featured monster hunter: Brad Spencer, McCall.

They are an enigma wrapped in a mystery, shrouded in secrecy.

A trout that’s not really a trout. A dweller of the deep that’s rarely seen. And a beast that, under the right conditions, can live up to 40 years and weigh a whopping 100 pounds.

Meet the mighty and mysterious Mackinaw trout.

First of all, to set the record straight, this “trout” is actually a char (it’s not an uncommon mistake — brook and bull trout also are char). The distinguishing characteristics of the char are their enormous, colorful fins and preference for icy cold water. And as char go, Mackinaws are king.

Like many Idaho monsters, Mackinaws only inhabit a handful of lakes. Their most commonly known chomping ground is Payette Lake — which sits right in the backyard of McCall angler Brad Spencer.

Spencer has been fishing for Mackinaws for the better part of a decade, primarily through the ice during the winter months. And like most truly huge fish, Mackinaws take a while to master.

“I went two full winters without catching anything,” Spencer said. “But once I figured out some lures and techniques that worked, I was addicted.”

Unlike their smaller cousins, Mackinaws feed almost exclusively on other fish. Kokanee salmon are the meal of choice, but Mackinaws will eat anything they can fit inside their gigantic jaws.

So how does one fish for them?

“Think of the big, ridiculous lures at the tackle store,” Spencer said. “The ones that are so huge you think, ‘There’s no way that would catch a fish.’ That’s what you want to use.”

In the summer, Mackinaws retreat to deep, cold water. Most anglers troll for them in 40-100 feet using big plugs, crankbaits and spoons.

But as the water cools, the fish become more active throughout the water column. And that’s when Spencer does his damage.

“I’ve caught them all over the place through the ice,” Spencer said. “It’s just about putting in the time and tinkering with your setup until you find what works. Once you get a few fish under your belt, you start to figure out the different ways they like the lures jigged.”

On a good day, Spencer will catch four or five fish, though he’s landed as many as 15 on his best trip. To date, his personal best is a 44-inch monster that weighed 38 pounds. He also was there this winter when his friend, Tom Henson, iced the 39.5-inch catch-and-release state record.

Despite their intimidating size, Mackinaws have some vulnerabilities. Fish hooked in deep water need to be brought up slowly so they can adjust to the changes in pressure. And the fish take many years to reach their massive size, so Spencer practices primarily catch and release. If you want to keep one, smaller fish in the 5- to 10-pound range tend to make better table fare.

Mackinaw fishing is tough sledding, and even seasoned anglers like Spencer get skunked on occasion. But beware: Once you crack the code, all other forms of ice fishing might be ruined for you.

“Yeah, I really can’t get into catching 2-pound perch,” Spencer said. “Not when I can fish for 20-pound Mackinaws that will peel off 100 yards of line and burn your thumb like a sturgeon.”

This story was originally published March 8, 2017 at 9:09 PM with the headline "Giant Mackinaw trout live in deep water, are rarely seen except on an angler’s hook."