Bull Trout in the Metolius by Gary Lewis

With the water swirling around us, we waded in at the mouth of Jack Creek. Skip Morris had hooked and lost a big rainbow here the day before. Today he stood back while Carol plumbed the two-foot deep run with a big stonefly nymph trailing a small beadhead attractor, called Gabriel’s Trumpet.

For a moment we thought Carol’s rig was hung up, but when she tightened the line, a fish torpedoed away. The fish rolled mid-river and I saw his tail and dark fins silhouetted against bright water: a bull trout. Close to eight pounds, I guessed. The line broke and Carol reeled in the slack. The fish had taken the big stonefly nymph after a 13-minute battle and a last headlong flight.

That’s what can happen when kokanee are on the move and bull trout follow them into the shallows.

LAKE RUN BULL TROUT

Kokanee are thickest in the Metolius in late September and October. And the biggest bull trout, which can get to 30 inches or more, hammer them. Bull trout are meat eaters and if it’s a third of their size they will crunch it. If it’s half their size, they will try to choke it down anyway. Anyone who has caught a bunch of big bull trout has seen the tail end of a kokanee or a whitefish sticking out of that gullet.

The Metolius River and Lake Billy Chinook are home to resident and migratory bull trout. The bulls move up the river to spawn in late August, September, and October. Oriented to ice-cold water, bull trout stage near springs and off the mouths of major tributaries like Canyon Creek and Jack Creek. After the spawn, they need to replace the calories they expended over the last few weeks. That’s when they find the kokanee.

The kokanee spawn puts both species in the river at the same time. And the bull trout are the winners. Preoccupied, the landlocked salmon are easy prey for sharp-toothed bull trout. Whitefish are on the menu for bull trout year-round, and many are the stories of anglers fighting whitefish only to lose them to bull trout which charge out from under a log to grab the hapless poor man’s bonefish.

Bull trout are apt to eat the limp, the lame, the lazy. It’s the erratic behavior that trips the predatory sear in a bull trout’s brain. Think strike triggers. Tie or buy streamers with big eyes, a flash of blood red near the gills. On the water, fish them on the wet fly swing, but give them action. Make the imitation twitch. Like a wounded fish in deep trouble.

Carol Ann Morris fights a bull trout on the Metolius. Photo by Gary Lewis

FISHING LAKE BILLY CHINOOK

A down-running Metolius River bull trout ends up running into Round Butte Dam and turning around to make its living in a 4,000-acre reservoir fed by three rivers: the Metolius, the Deschutes and the Crooked River. Best time to target bull trout in Lake Billy Chinook is when the waters begin to warm in March and April. Bull trout hunt close to shore in the late winter and early spring. Anglers who throw Zonkers and other minnow imitations on long casts and strip hard can elicit hard strikes from fish. It’s one of the best ways to get the biggest bull trout. A lot of 17- to 19-inchers will be brought to the net as well as the occasional 10-pounder.

SWINGING STREAMERS

When whitefish are schooled up, working the bottom, they are hard for bull trout to feed on, but when one of them leaves formation and streaks up to eat a mayfly emerger, its defenses are down and its easy money for bull trout.
When fishing a small streamer or a larger bunny leech, try to work it like a fish that is out of its element, a scared minnow that thought it could play in the deep end of the pool. It’s vulnerable. It’s lunch.

A variation on that theme is the sculpin. Bull trout eat sculpin year-round. In the river, they eat sculpin. In the lake – sculpin. When sculpin are doing what they do, daubing in the mud, they are pretty safe. But when they climb up through the water column or get caught in the current, something is going to nail them. Big lead eyes, blood-red gill flare or Flashabou, and prominent fins are some of the strike triggers to play on when tying sculpin flies.

Cast down and cross-current, let it swing and chug it. On long runs and into the tailout, let the sculpin work back and forth. Tied small, a sculpin imitation can be fished with a slackline presentation that keeps it working back and forth over bull trout holding water.

Think big. If a 30-inch bull can choke down a 12-inch whitefish, it will go for a 10-inch streamer. Big bunny leeches double as flesh flies. Just change the presentation.

DREDGING WITH A TWO-FLY RIG

As kokanee carcasses and decaying flesh become harder to find, bull trout begin to focus on bugs. Streamers and flesh flies can provoke a grab, but a dead-drifted nymph can pay off as well. To conserve strength, the biggest fish claim the best lies, hugging the bottom along downed timber and behind rock slabs and boulders. The major difference between drifting beadhead nymphs for rainbows and for bull trout is the length of the leader and the tightness of the presentation to the bottom. Fish the bottom. Keep the leader short so the dropper fly doesn’t ride too high in the water column.

Tie on a big, heavy stonefly nymph and knot eight to ten inches of fluorocarbon tippet material to the bend of the hook. The primary fly can be a Flashback Pheasant Tail, an egg pattern, or a No. 16 Serendipity. The main thing is to get that heavy fly bumping on the bottom. Make it easy! That bull trout should be able to spot the trailing dropper fly, lean its head over, and grab without leaving its lie.