Mammoth Creek Fish Stocking
IRON County, Utah · 1980–2026 on record
According to Utah DWR — Fish Stocking Report, Mammoth Creek was last stocked June 23, 2026 with Rainbow Trout. Mammoth Creek has 410 stocking records on file, spanning 1980–2026, with about 456,201 fish stocked over that period.
When Mammoth Creek is stocked
Mammoth Creek is typically stocked in summer, most often in June — 130 stocking events in that peak month.
By species
Angler's Field Guide
Fishing Tips & Stocking Guide for Mammoth Creek
Practical advice on fish behavior, recommended tackle, and state regulations for anglers fishing in IRON County, Utah.
Post-Plant Behavior & Timing
Hatchery-raised fish are conditioned to pelleted feed and open raceways. Following a release into Mammoth Creek, 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 Mammoth Creek was last stocked June 23, 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 Utah freshwater fishing license is required for anglers age 16 and older.Purchase Utah license online →
- •Official Rules & Limits: Bag limits, bait restrictions, and seasonal boundaries are set by Utah fish & wildlife agency.Official Utah 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 Mammoth Creek:
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 Mammoth Creek
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.
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 Mammoth Creek, freshest activity first.
Duck Creek
9 miKANE County · 2 species · 220 records
Last stocked June 2026
Asay Creek
6 miGARFIELD County · 3 species · 236 records
Last stocked June 2026
Panguitch Lake
7 miGARFIELD County · 8 species · 1109 records
Last stocked May 2026
Scout Lake
7 miIRON County · 3 species · 51 records
Last stocked May 2026
Bunker Creek
8 miIRON County · 2 species · 4 records
Last stocked September 2025
Deer Creek
8 miIRON County · 1 species · 2 records
Last stocked September 2025
Stocking history
Most recent stockings first. Dates shown at the precision the agency reported.
| Date | Species | Number | Size | Source |
|---|---|---|---|---|
| June 23, 2026 | Rainbow Trout | 242 | 10.54" | Utah DWR |
| May 20, 2026 | Tiger Trout | 500 | 10.19" | Utah DWR |
| May 18, 2026 | Rainbow Trout | 260 | 10.12" | Utah DWR |
| May 6, 2026 | Brown Trout | 3,046 | 3.28" | Utah DWR |
| July 8, 2025 | Rainbow Trout | 251 | 10.51" | Utah DWR |
| June 4, 2025 | Tiger Trout | 511 | 9.21" | Utah DWR |
| June 4, 2025 | Tiger Trout | 1,000 | 3.35" | Utah DWR |
| May 28, 2025 | Brown Trout | 3,780 | 4.11" | Utah DWR |
Show 42 more stocking records →
| Date | Species | Number | Size | Source |
|---|---|---|---|---|
| May 28, 2025 | Rainbow Trout | 252 | 10.21" | Utah DWR |
| May 21, 2025 | Tiger Trout | 1,020 | 9.93" | Utah DWR |
| July 18, 2024 | Rainbow Trout | 260 | 9.83" | Utah DWR |
| June 12, 2024 | Tiger Trout | 501 | 8.99" | Utah DWR |
| May 14, 2024 | Rainbow Trout | 258 | 10.47" | Utah DWR |
| May 14, 2024 | Brown Trout | 3,185 | 3.46" | Utah DWR |
| September 11, 2023 | Cutthroat Trout | 8,066 | 1.87" | Utah DWR |
| July 20, 2023 | Rainbow Trout | 240 | 9.9" | Utah DWR |
| June 27, 2023 | Tiger Trout | 605 | 10.75" | Utah DWR |
| April 19, 2023 | Brown Trout | 3,212 | 2.62" | Utah DWR |
| April 19, 2023 | Rainbow Trout | 264 | 9.9" | Utah DWR |
| September 12, 2022 | Cutthroat Trout | 12,359 | 2.01" | Utah DWR |
| July 12, 2022 | Rainbow Trout | 306 | 10.29" | Utah DWR |
| June 15, 2022 | Tiger Trout | 512 | 8.74" | Utah DWR |
| June 15, 2022 | Tiger Trout | 512 | 8.74" | Utah DWR |
| June 8, 2022 | Rainbow Trout | 252 | 10.97" | Utah DWR |
| April 19, 2022 | Brown Trout | 3,090 | 2.95" | Utah DWR |
| September 16, 2021 | Cutthroat Trout | 9,250 | 2.25" | Utah DWR |
| August 18, 2021 | Cutthroat Trout | 10,960 | 1.73" | Utah DWR |
| July 19, 2021 | Rainbow Trout | 1,650 | 10.24" | Utah DWR |
| July 13, 2021 | Tiger Trout | 1,449 | 9.78" | Utah DWR |
| July 1, 2021 | Tiger Trout | 1,557 | 9.48" | Utah DWR |
| June 15, 2021 | Tiger Trout | 304 | 10.23" | Utah DWR |
| May 11, 2021 | Rainbow Trout | 252 | 10.5" | Utah DWR |
| May 11, 2021 | Brown Trout | 3,620 | 4.17" | Utah DWR |
| July 7, 2020 | Rainbow Trout | 542 | 10.06" | Utah DWR |
| July 7, 2020 | Rainbow Trout | 783 | 10.06" | Utah DWR |
| May 26, 2020 | Rainbow Trout | 671 | 10.54" | Utah DWR |
| May 26, 2020 | Rainbow Trout | 724 | 10.54" | Utah DWR |
| April 20, 2020 | Brown Trout | 3,074 | 3.25" | Utah DWR |
| July 17, 2019 | Rainbow Trout | 744 | 10.13" | Utah DWR |
| July 17, 2019 | Rainbow Trout | 600 | 10.13" | Utah DWR |
| June 13, 2019 | Rainbow Trout | 750 | 9.99" | Utah DWR |
| June 13, 2019 | Rainbow Trout | 600 | 9.99" | Utah DWR |
| June 3, 2019 | Brown Trout | 3,951 | 3.91" | Utah DWR |
| July 10, 2018 | Rainbow Trout | 607 | 8.68" | Utah DWR |
| July 10, 2018 | Rainbow Trout | 750 | 8.68" | Utah DWR |
| June 19, 2018 | Brown Trout | 3,984 | 4.3" | Utah DWR |
| May 31, 2018 | Rainbow Trout | 597 | 10.02" | Utah DWR |
| May 31, 2018 | Rainbow Trout | 749 | 10.02" | Utah DWR |
| June 7, 2017 | Brown Trout | 3,064 | 3.62" | Utah DWR |
| July 20, 2016 | Rainbow Trout | 364 | 10.44" | Utah DWR |
Showing 50 of 410 stocking records.
Frequently asked
When was Mammoth Creek last stocked?
According to Utah DWR — Fish Stocking Report, Mammoth Creek was last stocked June 23, 2026 with Rainbow Trout.
What fish species are stocked in Mammoth Creek?
Mammoth Creek is stocked with Rainbow Trout, Tiger Trout, Brown Trout, Cutthroat Trout, and Brook Trout.
What time of year is Mammoth Creek stocked?
Mammoth Creek is typically stocked in summer, most often in June.
How often is Mammoth Creek stocked?
Mammoth Creek has been stocked about 9 times a year — 410 recorded stockings between 1980 and 2026.
How many fish have been stocked in Mammoth Creek?
About 456,201 fish have been stocked in Mammoth Creek across 410 recorded events since 1980, per Utah fish & wildlife agency.
What size are the fish stocked in Mammoth Creek?
Fish stocked in Mammoth Creek average about 8.1 inches, based on the sizes the agency reported.
Do you need a fishing license to fish Mammoth Creek?
Yes, all anglers age 16 and older generally need a valid Utah freshwater fishing license. Always review current regulations from Utah fish & wildlife agency for site-specific rules, bag limits, or stamps.
How do you catch stocked trout in Mammoth Creek?
Freshly stocked trout in Mammoth Creek 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.