Ostle Reservoir Fish Stocking
Montana · 1967–2025 on record
According to Montana fish & wildlife agency, Ostle Reservoir was last stocked June 26, 2025 with Rainbow Trout. Ostle Reservoir has 59 stocking records on file, spanning 1967–2025, with about 85,979 fish stocked over that period.
When Ostle Reservoir is stocked
Ostle Reservoir is typically stocked in summer, most often in June — 38 stocking events in that peak month.
Angler's Field Guide
Fishing Tips & Stocking Guide for Ostle Reservoir
Practical advice on fish behavior, recommended tackle, and state regulations for anglers fishing in Montana.
Post-Plant Behavior & Timing
Hatchery-raised fish are conditioned to pelleted feed and open raceways. Following a release into Ostle Reservoir, 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 Ostle Reservoir was last stocked June 26, 2025, 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 Montana freshwater fishing license is required for anglers age 16 and older.Purchase Montana license online →
- •Official Rules & Limits: Bag limits, bait restrictions, and seasonal boundaries are set by Montana fish & wildlife agency.Official Montana 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 Ostle Reservoir:
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.
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 Ostle Reservoir
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.
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Nearby stocked waters
Other stocked waters near Ostle Reservoir, freshest activity first.
Perkins Pond
11 mi1 species · 21 records
Last stocked June 2025
Bynum Reservoir
9 mi8 species · 167 records
Last stocked June 2024
Hope Lake
10 mi5 species · 26 records
Last stocked April 2008
Green Lake
11 mi3 species · 13 records
Last stocked May 2007
Long Lake
10 mi6 species · 29 records
Last stocked May 1995
South Fork Teton River
6 mi2 species · 19 records
Last stocked July 1963
Stocking history
Most recent stockings first. Dates shown at the precision the agency reported.
| Date | Species | Number | Size | Source |
|---|---|---|---|---|
| June 26, 2025 | Rainbow Trout | 1,200 | 3.7" | Montana fish & wildlife agency |
| June 26, 2025 | Rainbow Trout | 1,000 | 6.02" | Montana fish & wildlife agency |
| June 27, 2024 | Rainbow Trout | 1,020 | 3.96" | Montana fish & wildlife agency |
| June 5, 2024 | Rainbow Trout | 1,000 | 5.5" | Montana fish & wildlife agency |
| June 5, 2024 | Rainbow Trout | 1,000 | 3.3" | Montana fish & wildlife agency |
| June 27, 2023 | Rainbow Trout | 1,000 | 3.34" | Montana fish & wildlife agency |
| June 27, 2023 | Rainbow Trout | 1,000 | 5.71" | Montana fish & wildlife agency |
| June 14, 2023 | Rainbow Trout | 1,000 | 3.89" | Montana fish & wildlife agency |
Show 42 more stocking records →
| Date | Species | Number | Size | Source |
|---|---|---|---|---|
| October 26, 2022 | Tiger Trout | 20 | 8.44" | Montana fish & wildlife agency |
| June 27, 2022 | Rainbow Trout | 1,000 | 6.14" | Montana fish & wildlife agency |
| June 27, 2022 | Rainbow Trout | 930 | 3.79" | Montana fish & wildlife agency |
| June 16, 2022 | Rainbow Trout | 1,016 | 3.4" | Montana fish & wildlife agency |
| June 16, 2021 | Rainbow Trout | 1,000 | 3.81" | Montana fish & wildlife agency |
| June 1, 2021 | Rainbow Trout | 1,000 | 5.04" | Montana fish & wildlife agency |
| June 1, 2021 | Rainbow Trout | 1,000 | 2.97" | Montana fish & wildlife agency |
| June 25, 2020 | Tiger Trout | 20 | 10.45" | Montana fish & wildlife agency |
| June 16, 2020 | Rainbow Trout | 1,010 | 4.41" | Montana fish & wildlife agency |
| June 16, 2020 | Rainbow Trout | 527 | 3.39" | Montana fish & wildlife agency |
| June 2, 2020 | Rainbow Trout | 1,000 | 3.52" | Montana fish & wildlife agency |
| June 2, 2020 | Rainbow Trout | 1,000 | 2.97" | Montana fish & wildlife agency |
| July 8, 2019 | Tiger Trout | 20 | 4.89" | Montana fish & wildlife agency |
| June 19, 2019 | Rainbow Trout | 1,000 | 4.53" | Montana fish & wildlife agency |
| June 19, 2019 | Rainbow Trout | 1,000 | 3.75" | Montana fish & wildlife agency |
| June 4, 2018 | Rainbow Trout | 1,022 | 4.42" | Montana fish & wildlife agency |
| June 4, 2018 | Rainbow Trout | 1,003 | 3.4" | Montana fish & wildlife agency |
| May 25, 2017 | Rainbow Trout | 1,015 | 4.19" | Montana fish & wildlife agency |
| May 25, 2017 | Rainbow Trout | 1,000 | 3.4" | Montana fish & wildlife agency |
| June 2, 2016 | Rainbow Trout | 1,004 | 3.31" | Montana fish & wildlife agency |
| June 2, 2016 | Rainbow Trout | 967 | 4.42" | Montana fish & wildlife agency |
| June 17, 2015 | Rainbow Trout | 1,008 | 4.19" | Montana fish & wildlife agency |
| May 28, 2015 | Rainbow Trout | 2,003 | 4.27" | Montana fish & wildlife agency |
| October 9, 2014 | Rainbow Trout | 1,917 | 7.2" | Montana fish & wildlife agency |
| May 29, 2014 | Rainbow Trout | 2,005 | 4.12" | Montana fish & wildlife agency |
| September 20, 2013 | Rainbow Trout | 529 | 12.13" | Montana fish & wildlife agency |
| September 12, 2013 | Rainbow Trout | 1,989 | 9.2" | Montana fish & wildlife agency |
| June 18, 2013 | Rainbow Trout | 2,000 | 5.6" | Montana fish & wildlife agency |
| May 22, 2012 | Rainbow Trout | 2,000 | 4.8" | Montana fish & wildlife agency |
| July 7, 2011 | Rainbow Trout | 2,000 | 4.7" | Montana fish & wildlife agency |
| July 22, 2010 | Rainbow Trout | 1,000 | 9.9" | Montana fish & wildlife agency |
| June 25, 2009 | Rainbow Trout | 2,000 | 6" | Montana fish & wildlife agency |
| July 1, 2008 | Rainbow Trout | 2,000 | 5.1" | Montana fish & wildlife agency |
| June 6, 2006 | Rainbow Trout | 2,200 | 4.8" | Montana fish & wildlife agency |
| May 24, 2005 | Rainbow Trout | 2,000 | 4.16" | Montana fish & wildlife agency |
| June 25, 2004 | Rainbow Trout | 2,000 | 5" | Montana fish & wildlife agency |
| June 16, 2003 | Rainbow Trout | 2,000 | 4.7" | Montana fish & wildlife agency |
| May 30, 2002 | Rainbow Trout | 2,000 | 4.9" | Montana fish & wildlife agency |
| June 22, 1999 | Rainbow Trout | 2,000 | 4.8" | Montana fish & wildlife agency |
| May 28, 1998 | Rainbow Trout | 2,000 | 3.9" | Montana fish & wildlife agency |
| June 23, 1997 | Rainbow Trout | 2,000 | 4.6" | Montana fish & wildlife agency |
| June 27, 1996 | Rainbow Trout | 2,000 | 4.2" | Montana fish & wildlife agency |
Showing 50 of 59 stocking records.
Frequently asked
When was Ostle Reservoir last stocked?
According to Montana fish & wildlife agency, Ostle Reservoir was last stocked June 26, 2025 with Rainbow Trout.
What fish species are stocked in Ostle Reservoir?
Ostle Reservoir is stocked with Rainbow Trout and Tiger Trout.
What time of year is Ostle Reservoir stocked?
Ostle Reservoir is typically stocked in summer, most often in June.
How often is Ostle Reservoir stocked?
Ostle Reservoir is stocked intermittently — 59 recorded stockings between 1967 and 2025.
How many fish have been stocked in Ostle Reservoir?
About 85,979 fish have been stocked in Ostle Reservoir across 59 recorded events since 1967, per Montana fish & wildlife agency.
What size are the fish stocked in Ostle Reservoir?
Fish stocked in Ostle Reservoir average about 4.9 inches, based on the sizes the agency reported.
Do you need a fishing license to fish Ostle Reservoir?
Yes, all anglers age 16 and older generally need a valid Montana freshwater fishing license. Always review current regulations from Montana fish & wildlife agency for site-specific rules, bag limits, or stamps.
How do you catch stocked trout in Ostle Reservoir?
Freshly stocked trout in Ostle Reservoir 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.