Lake Merwin Fish Stocking
Cowlitz County, Washington · 1995–2026 on record
According to Washington fish & wildlife agency, Lake Merwin was last stocked July 13, 2026 with Rainbow Trout. Lake Merwin has 251 stocking records on file, spanning 1995–2026, with about 10,036,487 fish stocked over that period.
When Lake Merwin is stocked
Lake Merwin is typically stocked in spring and summer, most often in July — 61 stocking events in that peak month.
By species
Angler's Field Guide
Fishing Tips & Stocking Guide for Lake Merwin
Practical advice on fish behavior, recommended tackle, and state regulations for anglers fishing in Cowlitz County, Washington.
Post-Plant Behavior & Timing
Hatchery-raised fish are conditioned to pelleted feed and open raceways. Following a release into Lake Merwin, they typically congregate in schools near public access points, boat ramps, or inlets for the first 24 to 48 hours while adjusting to natural water conditions.
Since Lake Merwin was last stocked July 13, 2026, anglers visiting within 1 to 2 weeks of a reported event generally experience the highest activity before fish disperse into deeper cover.
State Regulations & Licensing
- •Fishing License: A valid Washington freshwater fishing license is required for anglers age 16 and older.Purchase Washington license online →
- •Official Rules & Limits: Bag limits, bait restrictions, and seasonal boundaries are set by Washington fish & wildlife agency.Official Washington regulations guidebook →
- •Ethical Conservation: Use barbless hooks and keep fish submerged in water during unhooking.Trout Thermal Advisory: When water temperatures rise above 68°F (20°C), released trout face severe mortality from thermal exhaustion. Target warmwater species or fish early in the morning when lakes and streams warm up.
Recommended Tackle & Presentations
Techniques tailored to the species stocked in Lake Merwin:
Stocked Trout Tactics
Use light 4–6 lb monofilament or fluorocarbon line. Float scented dough bait (PowerBait) 12–18" off bottom using a sliding slip-sinker rig with a size 14–16 treble hook. For active casting, throw 1/16 to 1/8 oz inline spinners (Panther Martin, Rooster Tail) or small spoons (Kastmaster) along drop-offs.
Kokanee & Salmon Tactics
Troll small dodgers followed by micro-hoochies or wedding ring spinners tipped with shoepeg corn. Use downriggers or lead-core line to reach cooler thermocline depths (typically 20–50 ft in summer).
Rainbow Trout Profile Tips
The most commonly targeted stocked trout in the country, taken on bait, spinners, and flies alike; a common first fish for new anglers.
Tiger Trout Profile Tips
Known for hitting lures and flies aggressively; a favorite for anglers seeking a distinctive, hard-fighting stocked trout.
Recommended Tackle for Lake Merwin
Field-tested tackle and presentations matched to the species stocked here.
Berkley PowerBait Floating Trout Dough
Hatchery-raised trout are conditioned to pelleted scents; scented dough floated 12–18 inches off bottom consistently triggers strikes.
Panther Martin Classic Teardrop Inline Spinner
The heavy convex blade spins instantly upon retrieval, sending vibration through the water that triggers aggressive reaction bites along drop-offs.
Sliding Sinker & Treble Hook Rigging Kit
Sliding egg sinkers allow cautious trout to run with bait without feeling line drag, while size 14–16 treble hooks keep dough bait securely pinned.
Mack's Lure Classic Wedding Ring Spinner
A classic Western trolling lure designed to be tipped with shoepeg corn and run behind a dodger in deep thermoclines.
As an Amazon Associate, StockedWaters earns from qualifying purchases at no additional cost to you. Recommendations are chosen for hatchery-conditioned fish behavior and ethical rigging. We may receive a referral commission if you buy through these links. Read our editorial policy & standards.
Nearby stocked waters
Other stocked waters near Lake Merwin, freshest activity first.
Battle Ground Lake
12 miClark County · 4 species · 546 records
Last stocked May 2026
Merrill Lake
10 miCowlitz County · 3 species · 22 records
Last stocked October 2023
Houghton Creek
11 mi1 species · 12 records
Last stocked April 2018
Pup Creek
6 mi1 species · 15 records
Last stocked March 2018
Indian George Creek
3 mi1 species · 3 records
Last stocked November 2017
Lakeview Peak Lake
6 miCowlitz County · 1 species · 11 records
Last stocked August 2014
Stocking history
Most recent stockings first. Dates shown at the precision the agency reported.
| Date | Species | Number | Source |
|---|---|---|---|
| July 13, 2026 | Rainbow Trout | 826 | Washington fish & wildlife agency |
| July 13, 2026 | Rainbow Trout | 821 | Washington fish & wildlife agency |
| July 13, 2026 | Rainbow Trout | 1,732 | Washington fish & wildlife agency |
| July 13, 2026 | Rainbow Trout | 1,732 | Washington fish & wildlife agency |
| April 29, 2026 | Tiger Trout | 1,950 | Washington fish & wildlife agency |
| February 23, 2026 | Kokanee | 5,710 | Washington fish & wildlife agency |
| October 1, 2025 | Kokanee | 35,570 | Washington fish & wildlife agency |
| July 14, 2025 | Rainbow Trout | 783 | Washington fish & wildlife agency |
Show 42 more stocking records →
| Date | Species | Number | Source |
|---|---|---|---|
| July 14, 2025 | Rainbow Trout | 784 | Washington fish & wildlife agency |
| July 14, 2025 | Rainbow Trout | 1,699 | Washington fish & wildlife agency |
| July 14, 2025 | Rainbow Trout | 1,699 | Washington fish & wildlife agency |
| April 29, 2025 | Tiger Trout | 1,939 | Washington fish & wildlife agency |
| March 1, 2025 | Kokanee | 50,700 | Washington fish & wildlife agency |
| October 7, 2024 | Kokanee | 45,750 | Washington fish & wildlife agency |
| July 15, 2024 | Rainbow Trout | 942 | Washington fish & wildlife agency |
| July 15, 2024 | Rainbow Trout | 942 | Washington fish & wildlife agency |
| July 15, 2024 | Rainbow Trout | 788 | Washington fish & wildlife agency |
| July 15, 2024 | Rainbow Trout | 765 | Washington fish & wildlife agency |
| May 6, 2024 | Tiger Trout | 869 | Washington fish & wildlife agency |
| March 1, 2024 | Kokanee | 52,850 | Washington fish & wildlife agency |
| October 5, 2023 | Kokanee | 40,500 | Washington fish & wildlife agency |
| July 10, 2023 | Rainbow Trout | 668 | Washington fish & wildlife agency |
| July 10, 2023 | Rainbow Trout | 906 | Washington fish & wildlife agency |
| July 10, 2023 | Rainbow Trout | 668 | Washington fish & wildlife agency |
| July 10, 2023 | Rainbow Trout | 891 | Washington fish & wildlife agency |
| May 9, 2023 | Tiger Trout | 2,020 | Washington fish & wildlife agency |
| October 9, 2022 | Kokanee | 22,380 | Washington fish & wildlife agency |
| August 29, 2022 | Kokanee | 49,540 | Washington fish & wildlife agency |
| July 13, 2022 | Rainbow Trout | 583 | Washington fish & wildlife agency |
| July 13, 2022 | Rainbow Trout | 979 | Washington fish & wildlife agency |
| July 13, 2022 | Rainbow Trout | 583 | Washington fish & wildlife agency |
| July 13, 2022 | Rainbow Trout | 988 | Washington fish & wildlife agency |
| July 13, 2022 | Kokanee | 22,860 | Washington fish & wildlife agency |
| May 9, 2022 | Tiger Trout | 1,600 | Washington fish & wildlife agency |
| January 31, 2022 | Kokanee | 42,680 | Washington fish & wildlife agency |
| October 29, 2021 | Kokanee | 48,580 | Washington fish & wildlife agency |
| June 8, 2021 | Rainbow Trout | 1,224 | Washington fish & wildlife agency |
| May 10, 2021 | Tiger Trout | 1,600 | Washington fish & wildlife agency |
| April 19, 2021 | Rainbow Trout | 3,000 | Washington fish & wildlife agency |
| April 19, 2021 | Rainbow Trout | 1,207 | Washington fish & wildlife agency |
| March 1, 2021 | Kokanee | 32,870 | Washington fish & wildlife agency |
| December 18, 2020 | Kokanee | 15,580 | Washington fish & wildlife agency |
| September 9, 2020 | Kokanee | 46,010 | Washington fish & wildlife agency |
| June 22, 2020 | Rainbow Trout | 1,065 | Washington fish & wildlife agency |
| June 17, 2020 | Rainbow Trout | 1,032 | Washington fish & wildlife agency |
| May 12, 2020 | Tiger Trout | 1,600 | Washington fish & wildlife agency |
| March 1, 2020 | Kokanee | 46,730 | Washington fish & wildlife agency |
| October 28, 2019 | Kokanee | 45,800 | Washington fish & wildlife agency |
| July 15, 2019 | Rainbow Trout | 571 | Washington fish & wildlife agency |
| July 15, 2019 | Rainbow Trout | 708 | Washington fish & wildlife agency |
The reporting agency did not include fish sizes for this water.
Showing 50 of 251 stocking records.
Frequently asked
When was Lake Merwin last stocked?
According to Washington fish & wildlife agency, Lake Merwin was last stocked July 13, 2026 with Rainbow Trout.
What fish species are stocked in Lake Merwin?
Lake Merwin is stocked with Rainbow Trout, Tiger Trout, Kokanee, Steelhead, Coho Salmon, Cutthroat Trout, and Chinook Salmon.
What time of year is Lake Merwin stocked?
Lake Merwin is typically stocked in spring and summer, most often in July.
How often is Lake Merwin stocked?
Lake Merwin has been stocked about 8 times a year — 251 recorded stockings between 1995 and 2026.
How many fish have been stocked in Lake Merwin?
About 10,036,487 fish have been stocked in Lake Merwin across 251 recorded events since 1995, per Washington fish & wildlife agency.
Do you need a fishing license to fish Lake Merwin?
Yes, all anglers age 16 and older generally need a valid Washington freshwater fishing license. Always review current regulations from Washington fish & wildlife agency for site-specific rules, bag limits, or stamps.
How do you catch stocked trout in Lake Merwin?
Freshly stocked trout in Lake Merwin typically respond well to floating dough bait (such as PowerBait) floated 12–18 inches off bottom on light 4–6 lb leader, live nightcrawlers under a bobber, and small inline spinners or spoons retrieved along shorelines and drop-offs.