Want to catch big fish? Of course you do, and if you want to consistently catch them, steelhead and salmon are your best bets. Let’s look at the tape, scale and ticker.
The average Idaho rainbow trout is around 10-14 inches and weighs about a pound. A “trophy” size rainbow is about 20 inches and weighs in the 4-pound range. A 30-inch rainbow is probably a once-per-lifetime fish that weighs in the 10- to 15-pound range.
Now let’s look at steelhead. Steelhead are rainbow trout that leave Idaho in the spring as juveniles known as “smolts” and migrate to the ocean, then spend about a year or two there before returning as adults that are much larger than trout.
The average-sized “A” run steelhead is between 23 and 26 inches and weighs 4 to 6 pounds. “A” run steelhead are most common in the Snake and Salmon rivers. Their larger cousins, the “B” run steelhead, are found mostly in the Clearwater system, although some are also in the Salmon and Snake rivers. The fish are genetically identical, but have a different life history. “B” run fish spend two years in the ocean and return much larger, typically 31 to 34 inches and 10 to 13 pounds.
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Big fish, big numbers
Over the last five years, an average of about 141,000 steelhead have returned to Idaho annually.
Adult steelhead start returning to Idaho in late summer and “winter over” in rivers before making their push to the upper tributaries in late winter and early spring to spawn. That gives anglers roughly seven months to fish for them with the most popular times during October and March.
Chinook salmon are even larger. They’re typically in the 12- to 15-pound range, but chinook over 20 pounds are common. Over the last five years, chinook returns to Idaho have averaged about 134,000 fish. The first chinook typically return to Idaho in late March and early April and are segregated into three runs: spring, summer and fall.
So let’s do some quick math. In recent years, Idaho gets about 275,000 steelhead and chinook annually, although run sizes vary from year to year. Steelhead and chinook dwarf your average trout and likely will exceed the largest trout you catch in a given year, and possibly in your lifetime.
Got your attention?
Unlike a once-per-lifetime trout, steelhead and chinook are plentiful, reliable, predictable and not difficult to catch. You need to have the right gear, know a few basic fishing techniques and know when to go.
You also need to know the basic rules. A full set of rules and seasons can be found in the Idaho Fish and Game fishing rules booklet, or online at fishandgame.idaho.gov. But a critical thing to know is that only hatchery steelhead and chinook can be harvested. You can identify a hatchery fish by the clipped adipose fin on the fish’s back directly in front of its tail. If the full adipose fin is intact, you have to release the fish unharmed. You will also need a permit to fish steelhead and salmon in addition to your fishing license.
Timing is (almost) everything
March is prime time for spring steelhead fishing and one of the best times for novice steelhead anglers to give it a try. The fish are in the smaller tributary streams, which means there’s easy access along highways and lots of fish in the rivers. Some favorite steelhead spots are the South Fork of the Clearwater River upstream from Kooskia, the Little Salmon River along U.S. 95 between New Meadows and Riggins, and the upper Salmon River between Salmon and Stanley along Idaho 75 and U.S. 93.
While you can be assured there will be ample steelhead in these rivers during March and April, conditions can vary wildly depending on rain or snow runoff. Rivers can go from low and clear to high and muddy within a day.
As a rule of thumb, most anglers prefer to fish for steelhead during spring when river temperatures are in the mid 30s to low 40s. Stable weather and consistent river flows tend to produce the best fishing. But even if conditions are imperfect, the fish are still there, and you can catch them. It’s just going to be more challenging.
Chinook start returning from the ocean in the spring and typically reach Idaho during, or shortly after, peak spring runoff. Fishing usually starts lower in the Snake and Clearwater around Lewiston in late April and May. Anglers follow the spring and summer chinook upstream through their migration all the way to the Sawtooth Valley near Stanley.
Fall chinook have a different life history. They start arriving in late summer, and unlike spring and summer chinook that spawn in headwaters, fall fish spawn in the lower river systems, mostly in the Snake River.
Gearing up to go
If you’re not used to tackling large fish, you will probably need to invest in some new gear. There’s a variety of steelhead and salmon rods available, and you need a reel with a good drag. Steelhead and chinook fight hard and are often hooked in strong river currents, so you will want line suitable for the battle. Use 10- to 15-pound test for steelhead, and 15- to 20-pound test for chinook. You may want to go heavier if you’re fishing strong current.
Check with your local tackle shop or sporting goods store to find suitable tackle. You also can get information about bobber and jig fishing, a popular method for both steelhead and salmon, at Fish and Game’s website on the pages for steelhead and chinook under the “Fishing” tab.
Steelhead and salmon fishing are popular in Idaho, and when the fish reach those smaller tributary streams, the banks can get crowded with anglers. Good etiquette means respecting other anglers’ space, and also not being a “hole hog” who takes over a popular fishing spot and excludes others.
Be assured there will be competition for prime spots, but in most cases, anglers have a good track record of working with each other so everyone gets a fair chance at hooking a fish.
The insider intel
There are several tools anglers can use to time their fishing trips during the prime times when fish are there and conditions are best:
- Columbia Research Station’s “Dart”: cbr.washington.edu/dart This website compiles data about steelhead and salmon and also tracks fish as they pass through the Columbia and Snake river dams. You can get daily counts at each dam, and also historic timing when the runs typically go though each dam.
- USGS Streamflows: waterdata.usgs.gov/id/nwis/current/?type=flow This website gives you real-time stream flows for most rivers in Idaho and water temperatures at some gauging stations. You can also find annual hydrograph charts that show when rivers typically get peak spring runoff.
- Pit tag data: http://www.ptagis.org/ This website provides information about fish that are embedded with small transmitters. There are pit-tag detectors in some Idaho streams, and anglers can use them to track the steelhead and salmon as they move upstream.