Upper Klamath Lake Oregon – Fly Fishing For Big Rainbow Trout

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In Fly Fishing the West’s Best Trophy Lakes, one of guide and stillwater specialist Denny Rickards’ earlier books, he wrote: “Upper Klamath Lake is considered by many to be the best trophy rainbow trout lake for fly fishermen in the country. I’d have to agree.”

In more recent years, the lake (often simply known as Klamath Lake) has suffered harsh algae blooms and harsher summertime conditions with lowered levels of dissolved oxygen in the water.

But this massive, shallow lake near Klamath Falls (not far north of the California border) remains a trout-food factory that quickly fattens the resident rainbows so they rival (and can exceed) their ocean-going steelhead kin for size.

Agency Lake is connected to the north side of Upper Klamath by a narrow channel, and Rickards considers them a single fishery.

Thanks to these massive native redband rainbows, we’ve listed this fishery among Oregon’s best rainbow trout lakes as well as among our best fly fishing lakes in Oregon.

Besides the rainbows, a native variety that are among the largest in the West, the lakes also have large populations of yellow perch, brown bullhead catfish and various forage fish.

The tributary rivers and streams hold brown and brook trout (and Rickards has even seen some kokanee that likely flushed down from Fourmile Lake), but these species would be a rarity to find in the lake itself.

Tributaries include the Williamson River and Wood River, both prime trout streams, and many smaller creeks.

Klamath and Agency Lakes Regulations

Klamath and Agency, in ODFW’s Southeast Zone, are open all year. Bait is allowed only in Klamath Lake.

The trout limit is one per day, with an 15-inch minimum, in Klamath Lake only. At last check, Agency Lake was strictly catch and release.

Know Before You Go

Summer visitors should be prepared for the incredible abundance of tiny green midges and thick algae in much of the lake, especially by mid- to late summer.

When to Fish Trout

There are fishing options here year-round, but due to the lakes’ unique conditions being in the right place during the proper season is just about everything here.

Counter to some lakes, the dog days of summer actually can be the most productive time to fish Klamath and Agency.

Why? The simple reason is that harsh conditions such as warm water and algae blooms force the trout out of much of the main lake and concentrate them in zones with better water.

During the warmer season, fish the main lake very early because the algae thickens under the morning sun, dissolved oxygen decreases and the fish are too stressed to bite well.

By 10 a.m., if you’re not ready to head home, go to Pelican Bay or the mouths of streams. Here fish usually will bite longer in cooler water.

Where to Fish Trout

Hint: Look for Cooler Water

Summertime fishing will find many anglers in Pelican Bay, a finger jutting off the northwest end of the main lake.

This bay is a smaller water body fed by several smaller tributaries coming off the Cascade Mountains, so it stays cooler and clearer in hot weather. The best fishing here begins in mid-June and holds up through summer.

Within Pelican Bay there are many places to fish. Rickards suggests that someone new to the fishery start near the mouths of feeder streams and then explore other parts of the bay.

In the summer months fish also will seek refuge at the Fish Bank area near the mouth of Pelican Bay, several spring sites (especially within Pelican Bay), and at the mouth of the Williamson River on the northeast side of Upper Klamath Lake.

The Williamson River mouth can be good for much of the year, including late season when fish stage for spawning runs.

Before this, in the early spring, Pelican Bay runs very cold and fish tend to be less active.

Instead, big trout can more often be found in the main lake, especially along the shorelines where they feed on leeches while moving north toward tributaries and springs that provide better summer conditions.

The mouth of the Wood River on the north end of Agency Lake, especially during the spring and fall, can be a productive fishery.

In the fall, many of the trout move southward again but aren’t usually hugging the shore as they do in the spring. At this time of year they are mostly feeding on small fish such as shiner minnows and chubs.

A fair number of trout will hold in the lake’s southern reaches and down into the Link River for the winter months, and at this time they are most accessible from shore close to Klamath Falls and along road and railroad access points.

How to Catch Trout

The big trout in the main lake feed largely on small fish, making a 2- to 4-inch chub or shiner minnow imitation with a silver body and darker top is ideal.

So, too, are seal bugger and leech patterns in sizes 6 and 8. The seal buggers are often best in black or olive. The leeches are good in the same colors plus brown or burgundy.

Stillwater or Callibaetis nymph patterns, in sizes 10 to 14, can be very effective when fish feed near surface, especially in Pelican Bay.

An AP (all purpose) emerger or any small nymph pattern representing a common aquatic insect is an excellent choice in the bay, which has mayfly, caddis, damsel and midge hatches.

A fine fly rod for fishing these lakes is a 9- or 9½-foot graphite built for a 6- or 7-weight line. He prefers a custom rod with a strong butt section and soft tip, ideal for the lake’s big trout and strong winds.

An intermediate line will serve fly anglers well on the large, shallow lakes and also in the shallow areas of Pelican Bay, where most fish hold in 5 or 6 feet of water.

If you want to reach deeper water in the bay, a transparent or Type II uniform sink line might be a better choice.

If All Else Fails

Movement is the most-important factor in catching fish on a fly (and other methods). Make sure to impart an enticing action to your presentation. Bring the fly back in an erratic line with twitches and turns, not in a straight line.

Leeches, streamers and buggers are ideal fly pattern families for stillwater fishing because they translate each of your movements into a fly motion that trout often can’t resist.

Even in Klamath and Agency lakes, where Rickards says the fish don’t feed much during the summer due to warm water, they can be more easily fooled by using plenty of movement with a highly “suggestive” fly pattern such as a leech or bugger.

Return to Oregon Trout Fishing

Oregon Resources

ODFW Weekly Fishing Report
ODFW Trout Stocking Schedule
Oregon Fishing Regulations
National Weather Service

Denny Rickards of Fort Klamath, owner of Crystal Creek Anglers and Stillwater Fly Fishing Systems, is a fishing innovator, fly tier and author. He guided clients for many years on Upper Klamath and Agency lakes and is past owner of Rocky Point Resort. He still fishes the big lakes but now conducts most guided trips and seminars on private waters, including Hyde Lake on nearby Yamsi Ranch. His latest book is Stillwater Presentation.