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  • Merrill Lake Outing (Mini-Fishouts Thursday Evenings in July & August)


  • The Lake

  • Each summer, CSF members meet on Friday evenings between 7:00 and 8:00 PM at the Merrill Lake launch ramp to fish the famous Hexagenia mayfly hatch. This lovely fly-fishing-only lake is perched just north of Cougar on FR 81, which leads to the Kalama Horse Camp and to the south side of Mount St. Helens. Float tubes, kick boats or canoes are a must on this body of water; boats with electric motors are permitted.

  • IMPORTANT: once the sun goes down behind the mountains, this lake gets DARK, so a light is a must. To keep your hands free, a headlamp is highly recommended.

  • The Fishing

  • The giant Hexagenia mayfly is about an inch long and looks like a floating hummingbird on the water. The hatch starts around 9:00 PM and can last between 15 minutes and a couple of hours. On some occasions, the hatch can last until 10:30 or11:00 PM. Large yellow/tan dry flies, emergers, and nymphs should all work at some time during the hatch. If you don't tie, most fly shops in the area carry some hex patterns. I recommend a 5 or 6 weight rod with a 3X tippet on the end of your leader. The trout have been known to rip off many flies. Bill Brown landed a 24" brown about four years ago, and I have heard tales of even bigger browns being landed. It's nighttime fly-fishing at its best.

  • Patterns


Hex Nymph (Brian Silvey) - 1st Choice
Hook: TMC 200R, #4
Thread: Light yellow 6/0
Tail: 3 brown dyed ostrich herl
Thorax and Abdomen: Light yellow Hare-tron
Gills: (in 3 sets) root beer dyed marabou
Wing Case: Large clump of pheasant tail fibers to form shell back
Legs: Ends of wing case fibers split pulled back from legs
Head: Light yellow Hare-tron with black mini plastic eyes


Hex Nymph - 2nd Choice
Hook: 3X long nymph, size 4 to 8. Mustad 9672, 38941; Tiemco 5263, 200R; Daiichi 1720
Thread: Tan 6/0 Danville or 8/0 Uni-thread
Tail: Gray down from the base of a Ringneck pheasant body feather
Rib: Fine amber or light brown vinyl rib
Thorax and Abdomen: Pale grayish yellow dubbing
Abdominal Gills: Gray filoplume
Legs: Partridge or grouse body feather
Back and Wing Case: Dark turkey tail strengthened with Dave's Flexament


Hex Emerger (Mark Bachmann) - 3rd Choice
Hook: TMC 200R, #8
Thread: Light yellow 6/0
Tail/Back: Brown Hi-Vis body length to form part of trailing shuck
Rib: Fine brown V-rib
Thorax and Abdomen: Light yellow Hare-tron
Legs: Dyed Wood Duck mallard flank fibers
Wing: 4 CDC feathers 1/2 body length
Legs: Ends of wing case fibers split pulled back for legs
Head and Eyes: Light yellow Hare-tron with black mini plastic eyes


  • Fishing Reports

  • For up-to-date information, check with the local fly shops and review the Stream Reports.

  • Camping

  • Although the CSF Merrill Lake fish-outs are day trips, anyone wishing to camp may do so. There is a State of Wash. campground adjacent to the ramp area, DNR (Dept. of Natural Resources, S.W. region 1-800 527.3305).

  • Directions

  • Take State Highway 503 from Battle Ground or Woodland past Yale Lake, turn left at the "Merrill Lake - 4 Miles" sign. Drive in on the new road to the boat ramp. Unload your preferred watercraft and park. Look for vehicles w/ CSF stickers or familiar faces. For details, see DeLorme's Washington Atlas and Gazetteer, page 33, D-6. Drive slowly on the road past the gate to avoid raising dust in the camping/parking area.

  • Contacts

  • To contact the outing Fishmaster, go to the Calendar page.

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