Ostle Reservoir fishing

Ostle Reservoir fishing has Rainbow Trout and Tiger Muskie on the stocking report. Also recorded: Lake Chub, Brook Stickleback, and White Sucker. It is stocked about 2.5 times a year since 2011, most often in May and June. Species guides list dawn and dusk as the active times.

AI-generated illustration, not a photo of this lake
Last stocked
September 11, 2026
· Rainbow Trout
Plants on record
40
Since 2011
Species stocked
2 (+3 also recorded)
Average size
4.9 in
Elevation
4,798.4 ft

Fish at Ostle Reservoir

2 stocked · 3 confirmed present

Around the dates Ostle Reservoir is stocked, Open-Meteo's 2016-2025 archive puts mean air temperature at 56.7°F in June, 48.2°F in May, 55°F in September, 65.4°F in July. That is air temperature at these coordinates, not water temperature. Open-Meteo

Rainbow Trout Stocked · 37 plants · last September 11, 2026 Best: dawn, dusk

Last stocked September 11, 2026 · avg 4.6 in · 37 plants

Best: dawn, dusk

Rainbow Trout species guide
Tiger Muskie Stocked · 3 plants · last October 26, 2022

Last stocked October 26, 2022 · avg 7.9 in · 3 plants

Tiger Muskie species guide

How Ostle Reservoir is stocked

Source: Montana Fish, Wildlife & Parks.

Fish stocked in 2011

2,000

Fish stocked in 2012

2,000

Fish stocked in 2013

4,518

Fish stocked in 2014

3,922

Fish stocked in 2015

3,011

Fish stocked in 2016

1,971

Fish stocked in 2017

2,015

Fish stocked in 2018

2,025

Fish stocked in 2019

2,020

Fish stocked in 2020

3,557

Fish stocked in 2021

3,000

Fish stocked in 2022

2,966

Fish stocked in 2023

3,000

Fish stocked in 2024

3,020

Fish stocked in 2025

2,200

Fish stocked in 2026

2

Stocking history

Source: Montana Fish, Wildlife & Parks.
Date Species Quantity Avg. length Source
September 11, 2026Rainbow Trout14.04 inreport
September 11, 2026Rainbow Trout13.97 inreport
June 26, 2025Rainbow Trout1,2003.7 inreport
June 26, 2025Rainbow Trout1,0006.02 inreport
June 27, 2024Rainbow Trout1,0203.96 inreport
June 5, 2024Rainbow Trout1,0005.5 inreport
June 5, 2024Rainbow Trout1,0003.3 inreport
June 27, 2023Rainbow Trout1,0005.71 inreport
June 27, 2023Rainbow Trout1,0003.34 inreport
June 14, 2023Rainbow Trout1,0003.89 inreport
October 26, 2022Tiger Muskie208.44 inreport
June 27, 2022Rainbow Trout9303.79 inreport
June 27, 2022Rainbow Trout1,0006.14 inreport
June 16, 2022Rainbow Trout1,0163.4 inreport
June 16, 2021Rainbow Trout1,0003.81 inreport
June 1, 2021Rainbow Trout1,0005.04 inreport
June 1, 2021Rainbow Trout1,0002.97 inreport
June 25, 2020Tiger Muskie2010.45 inreport
June 16, 2020Rainbow Trout5273.39 inreport
June 16, 2020Rainbow Trout1,0104.41 inreport
June 2, 2020Rainbow Trout1,0003.52 inreport
June 2, 2020Rainbow Trout1,0002.97 inreport
July 8, 2019Tiger Muskie204.89 inreport
June 19, 2019Rainbow Trout1,0003.75 inreport
June 19, 2019Rainbow Trout1,0004.53 inreport
June 4, 2018Rainbow Trout1,0033.4 inreport
June 4, 2018Rainbow Trout1,0224.42 inreport
May 25, 2017Rainbow Trout1,0003.4 inreport
May 25, 2017Rainbow Trout1,0154.19 inreport
June 2, 2016Rainbow Trout1,0043.31 inreport
June 2, 2016Rainbow Trout9674.42 inreport
June 17, 2015Rainbow Trout1,0084.19 inreport
May 28, 2015Rainbow Trout2,0034.27 inreport
October 9, 2014Rainbow Trout1,9177.2 inreport
May 29, 2014Rainbow Trout2,0054.12 inreport
September 20, 2013Rainbow Trout52912.13 inreport
September 12, 2013Rainbow Trout1,9899.2 inreport
June 18, 2013Rainbow Trout2,0005.6 inreport
May 22, 2012Rainbow Trout2,0004.8 inreport
July 7, 2011Rainbow Trout2,0004.7 inreport

Access and facts

Nearest town
Choteau
Facilities
restrooms, camping

Also called Antelope Butte Reservoir, a 39-acre water inside FWP's Blackleaf WMA, with a fishing access site offering toilets and camping. From Choteau take US 89 north 5.2 mi, Teton Canyon Rd 13.6 mi, then Blackleaf Cutacross Rd about 9 mi.

Drafted by AI from the cited sources and checked before publishing.

View larger map · Open in Google Maps · Directions

Advisories, closures, regulations and water conditions change. Check the Montana Fish, Wildlife & Parks before you go.

Nearest lakes

Bynum Reservoir 9.2 mi last stocked June 5, 2024 Eureka Reservoir 16 mi last stocked May 27, 2021 Duck Lake 16.4 mi last stocked May 12, 2026 Pishkun Reservoir 20.9 mi last stocked May 1, 2026 Tunnel Lake 22.4 mi last stocked May 21, 2026

Common questions

What fish are at Ostle Reservoir?

Fishing Ostle Reservoir usually means Rainbow Trout: Rainbow Trout accounts for 37 of 40 plants on record, ahead of Tiger Muskie. Rainbow Trout was last stocked September 11, 2026, averaging 4.6 in. Tiger Muskie was last stocked October 26, 2022, averaging 7.9 in. Lake Chub, Brook Stickleback, and White Sucker are recorded here outside the stocking reports.

When is Ostle Reservoir stocked?

Last stocked September 11, 2026. It is stocked about 2.5 times a year since 2011, most often in May and June.

How big are the fish stocked at Ostle Reservoir?

Stocked fish average 4.9 in. Rainbow Trout average 4.6 in. Tiger Muskie average 7.9 in.

How do you get on Ostle Reservoir?

The nearest town is Choteau. Facilities include restrooms and camping. Also called Antelope Butte Reservoir, a 39-acre water inside FWP's Blackleaf WMA, with a fishing access site offering toilets and camping. From Choteau take US 89 north 5.2 mi, Teton Canyon Rd 13.6 mi, then Blackleaf Cutacross Rd about 9 mi.

Sources (2) +