Washington Rivers


What to Expect in April

Note: This What-To-Expect is from Westfly's Legacy pages and may not accurately reflect the current fishing at this venue.

The best April weather is mild: not too hot, because that melts the snow, which muddies the rivers; not too cold, because that will slow down the hatches; not too rainy because that will muddy the rivers too. Where ever you go, check the river levels and the weather forecast.

Blue-winged olives, March browns, and mahogany duns are the mayflies of interest this month, and caddis and midges will also be hatching. Stonefly nymphs will be active, as well, and will catch the interest of trout; Skwala stonefly adults are around, but they will fade about the second or third week of April.

For the blue-winged olives, size18-22 patterns such as Sparkle Duns and Baetis Cripples work well during hatches, as do Parachute Baetis and small Comparaduns. In general, the best action will be 2:00 p.m. -4:00 p.m. (daylight time). If you want a little more fishing, tie on a size 18 Gold-Ribbed Hares Ear or a Pheasant Tail and drift it near the bottom during the pre-hatch hours. A good way to get these small flies down on the bottom is to pinch a split shot onto the leader or to use a tandem fly rig with a heavy fly such as a Rubber Legs on the point and the small fly on a dropper about 12 inches above it.

Runs of slow to moderate speed are best for the blue-winged olive nymphs, but the dry flies work best in backeddies and along current seams. Post-hatch, try a Diving Baetis to pick up trout feeding on egg-laying females.

March brown mayfly hatches will continue on many rivers. Carry size10 and 12 Comparaduns or CDC Cripples. Look for feeding fish in slow-to-moderate runs that are near riffles. March brown nymphs migrate from riffly water to slower water before they hatch. That migration could be upstream, downstream, or across stream. So you don't just find duns hatching below riffles; you can find them below, above, or near riffles. After hatching, the duns may drift into a backeddy or current seam, so look there, too.

Another mayfly you'll find on some rivers this month is the first round of the mahogany duns. The nymphs migrate to slow water along the margins of the river before they hatch. Because the hatch is in slow water, you need to avoid blind casting. Instead, wait until a trout rises, then cast upstream of that spot. If you cast blindly you risk putting the fish down before you hook any.

Caddis are very important this month and next. The larvae of green caddis (green rock worms, genus Rhyacophila) and spotted caddis (genus Hydropsyche) often drift in the current and are taken by trout. Princes, Green Rock Worms, and Net Builders are good fly choices.

Expect occasional hatches of green rock worms around2:00 p.m. to 4:00 p.m. in soft water below riffles. A dark Elk Hair Caddis in sizes 12-14 can work well, but emerger patterns such as a Soft Hackle or Sparkle Pupa are usually better. Emergers should be presented just subsurface, either on a dead drift or with a surface swing. The green rock worms will hatch through April and part of May, then come back again in fall.

Saddle-case caddis (genus Glossosoma) also hatch throughout April in the afternoon, and some grannoms (genus Brachycentrus) may show up near the end of April.

Stoneflies are the other game in town. Trout will begin picking up the large salmonfly and golden stonefly nymphs. The spring stonefly, or Skwala, is still a factor this month. It is a kind of gray-olive color, about size8-10. Carry some Stimulators (an olive body with a hint of yellow around the thorax) or Bitterroot Olive Stoneflies in that size.

Above all, remember that rainbow trout and steelhead are now spawning. Avoid spawning beds (redds). They show up as clear patches in the gravel. Don't walk through them, anchor over them, or target trout or steelhead that are on them.


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