Fall fishing forecast

October 13, 2020
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Sheridan -

While many folks might be focused on big game hunting plans this fall, fishing in the autumn months can also be rewarding for anglers seeking water time on area reservoirs or mountain streams.

The big thing in the fall is that water temperatures drop. As water temperatures cool off, trout become more active near the shorelines and shallower areas. Walleye can also begin feeding more.

One thing that overlaps with hunting season is brook and brown trout start spawning in late October and early November. They start to move a lot, get aggressive, and you can catch them more easily. It is a good time to fish for those two species, for sure.

Sheridan area

North Tongue River

Certainly our most popular water in the northern Bighorns is the North Tongue River and it continues to impress. Despite cold water temperatures and a short growing season, the North Tongue produces many fish of decent sizes. Our management objective for the fishery is to maintain 30 percent of the trout population at 12 inches or larger. Since 2010, the North Tongue has been at or above this objective. Since 2012, between 65 and 75 percent of the fish captured during sampling were 10 inches or larger.

Overall population estimates throughout the river have dipped from a high in 2008, however, we currently have more big fish . Even with trout numbers lower than the recent past, the North Tongue River is still one of the best fisheries in the Bighorns.

South Tongue River

Most fly-fishing enthusiasts fishing the Bighorns usually target the North Tongue or the Middle Fork Powder rivers- our most popular rivers. A river that can be just as good but has less angling pressure is the South Tongue River. Tributaries of the East Fork South Tongue River begin on Woodchuck Pass and Sawmill Divide while the West Fork South Tongue begins on Bruce Mountain. Both flow north until they combine to form the South Tongue River just upstream of Dead Swede Campground.

The South Tongue continues north approximately 15 river miles until it joins the North Tongue, forming the Tongue River above Box Canyon. The South Tongue is primarily occupied by brown and brook trout but rainbow trout appear in greater numbers as you move downstream (north) towards the confluence with the North Tongue.

The South Tongue and its tributaries are truly remarkable. There are several locations that are easy to access and there are miles of river with more rugged access points. You can plan a trip that suits any of your needs, from remote dispersed camping to several established campgrounds; from access next to Highway 14 to an isolated 6 mile stretch between Prune Creek and Tie Flume campgrounds. For the South Tongue River and its tributaries you can harvest six trout (browns and rainbows combined) and 16 brook trout. Although the trout are not typically as large as the North Tongue, being able to keep 22 trout will provide a few good meals.

Sibley Lake

With easy access, developed campgrounds and a really nice handicap-accessible fishing pier, Sibley Lake is one of the busiest fisheries in the Bighorns. It is common to see anglers lined up on the shore and several boats enjoying this beautiful lake, especially on a nice weekend day. In past years, Game and Fish stocked Sibley with 5,000 catchable-sized (8-10 inches) Yellowstone cutthroat trout each year. However, earlier this year, we switched from stocking catchable Yellowstone cutthroat trout to catchable rainbow trout.  In addition to the stocked rainbows, Sibley supports populations of wild brook and brown trout.

To determine angler success with this newly added species, we have placed creel survey cards in two locations at the lake, asking for feedback on a few short questions including what species and how many were caught. So if you fish Sibley in 2020, please take the time to fill out an angler card each time you fish to help us better manage the fishery.


Gillette Area

Sand Creek

One of the most unique fisheries in the Sheridan Region and one of the prettiest places in Wyoming is Sand Creek, located in northeast Wyoming near Beulah. Historically, Sand Creek has boasted one of the highest biomasses (pounds of fish/mile of stream) of any stream in Wyoming with estimates of nearly 1,500 pounds per mile.

Sand Creek is a very productive stream. There are good spawning gravels throughout the creek, tons of watercress and other aquatic vegetation which harbors food and cover, and a plethora of aquatic invertebrates.

Most of the browns and rainbow trout we have sampled in past years averaged 8 and 12 inches, but there are some larger fish from 18 to 24 inches. Fishing can be tough at times. If there is ever a place that the old adage of “make that first cast count” proves true, it’s Sand Creek. Crystal clear water, coupled with the majority of fish being wary and secretive, can make catching fish quite the task, even for the most experienced of anglers. If you are up for a challenge, give Sand Creek a try.

Cook Lake

A long awaited project came to fruition in late 2019.  Cook Lake, a 31-acre reservoir in the Black Hills National Forest, north of Sundance, was mostly drained, chemically treated to remove undesirable fish and dam repairs were made. This project was initiated by the Black Hills National Forest which secured funding and found a Bureau of Reclamation construction crew to make the necessary dam and spillway repairs.

Grading and rip-rap placement was completed and several thousand rainbow and tiger trout were stocked in the lake in spring 2020. Prior to this project, Cook Lake was a marginal fishery at best. It was overwhelmed with undesirable species such as green sunfish, white suckers and black bullheads. These fish were plentiful and competed with the rainbow and Snake River cutthroat trout that we stock annually, resulting in poor performance and survival.

Suckers, sunfish, and bullheads inhabit the creek above the lake, making a complete eradication impossible. But it is our hope that the newly stocked trout will grow well in the absence of the undesirables, so that when suckers, sunfish, and bullheads return, there will be predators big enough to prey upon them.

LAK Reservoir

Northeast Wyoming residents are lucky to have the diverse warm water fishery found at LAK Reservoir five miles southeast of Newcastle, just north of Highway 16. Here you can catch walleye, tiger muskie, smallmouth bass, yellow perch, green sunfish, white crappie and brown trout.

A formal access agreement was established with True Ranches in 2016 to ensure fishing and boating access for 25 years (permission slips are no longer required). This crystal-clear 120-acre lake is fed by enormous springs in the upper valley of Stockade Beaver Creek. Fish habitats vary at LAK from steep, rocky shoreline adjacent to deep water at the dam and cliffs on the west side, to shallow coves with dense weed beds with emergent bulrush on the east side and near the inlet.

Game and Fish stocks about 10,000 walleye fingerlings (1.5 to 3 inches long) at LAK every year. However, their previous abundance has not rebounded in response to consistent stocking started in 2015. Green sunfish were still booming in that first year of stocking and they probably put a dent in the fingerlings we stocked, along with predation from a growing yellow perch population.

We aren’t sure why the walleye population has not rebuilt. But we can say with certainty, that the walleye that you’ll catch at LAK are nice fish. In 2020, we sampled walleye from 17 to 25 inches. They averaged 20.0 inches and had excellent body condition.  The yellow perch population is growing at LAK, and many fish were observed in the 8 to 10 inch range.  


Keyhole Reservoir 

Fall fishing is generally good at Keyhole Reservoir, northeast of Moorcroft, Wyoming. Strong populations of crappie, walleye, and northern pike are currently present within the reservoir.  As water temperatures begin to cool down, fish within Keyhole tend to feed fairly aggressively prior to the onset of winter.  Crappie and walleye tend to be suspended over deeper water chasing gizzard shad.  Fishing from shore can still be good in the fall as well with occasional walleye or northern pike cruising looking for forage.  With ten game fish species present at Keyhole (bluegill, green sunfish, yellow perch black and white crappie, walleye, northern pike, channel catfish, freshwater drum, and smallmouth bass) there are numerous opportunities available. 


Buffalo Area

Healy Reservoir

There are lots of nice tiger muskie and largemouth bass in Healy right now. Several anglers have reported tiger muskie over 40 inches and largemouth bass five pounds or heavier.

The overall size structure of yellow perch in Healy continues to be small, with very few perch exceeding six inches during sampling efforts. We believe that anglers, along with the large predators, are taking out most of the larger perch.

Healy is still a great place to take a kid fishing and currently a great place for a chance at a trophy-sized fish. Please remember, Healy is a day use fishery only and no camping or fires are allowed.  A new permanent bathroom was installed at Healy this summer - no more porta potty!   A new dock will be installed soon to make launching and retrieving a boat easier.  Remember only motors less than 15 horsepower are allowed to be used.  

Lake DeSmet

About 40,000 fingerling kokanee (3 -4 inches) were stocked in April 2019. Kokanee are landlocked sockeye salmon that live mostly “off shore” in lakes and filter feed in the water column on small crustaceans called zooplankton. Though it will be another couple years before they reach full maturity, some anglers have reported catching a few between seven and 13 inches in depths of 40 to 70 feet.

The rainbow trout fishery at Lake DeSmet has struggled but gill net catch rates appeared to rebound in early 2020, from a steady downward trend since 2016. The Eagle Lake strain of rainbow trout was very popular at DeSmet for decades, particularly with shore anglers because they were known for “running the shoreline” in the spring. Game and Fish has been marking Eagle Lake rainbows before they are stocked.   We had seen very few of them during our gill net surveys until spring of 2020.   The improved survey results are promising and we hope it translates into better fall fishing.  

Most of the rainbow trout caught at DeSmet now are “fall strain,” which were bred to spawn in a hatchery during the fall. Big walleye, lake trout and brown trout are also common at Lake DeSmet and provide excellent opportunities for a trophy fish!

Muddy Guard Reservoir #1

Muddy Guard #1 sits in a fairly sheltered location in the Muddy Creek valley about 16 miles southwest of Buffalo, just off of Crazy Woman Canyon Road. Striking scenery combined with phenomenal trout fishing guarantee that you’ll have a good day here. This is a great place to take your car-topper boat, float-tube, kayak, or canoe. It is a productive 27-acre reservoir managed for trophy trout. As such, you can fish only with artificial flies and lures and may take home one 20-inch wall-hanger. This fishery is small and no secret, so recycling its fish is key to keeping the fishing good. Game and Fish carefully maintains this stellar fishery by stocking about 900 trout per year, in several flavors. Snake River cutthroat and rainbow trout are the bread-and-butter here. The cutties are most abundant, averaging 16 inches and around 2 pounds!

Game and Fish began stocking more tiger trout in 2019 to boost their numbers. The number of tiger trout found during surveys and reported by anglers has been low but the fish were large and healthy, with some exceeding 20 inches. Low numbers of wild brown trout add to the diversity of fish at Muddy Guard #1 and we routinely sample a brown over 24 inches. Keep a lookout for brook trout too. Extra brookies were available in our hatchery system in 2019, so we stocked a few at Muddy Guard #1. We expect them to grow well and become a fantastic addition to the fishery.

Muddy Guard Reservoir #2

Look no further than Muddy Guard #2 if you’re looking for a trophy brown trout. This 50-acre fishery, on the North Fork of Crazy Woman Creek, is also southwest of Buffalo, and not far from the Crazy Woman Canyon Road. Access over the south dam allows float tubes, small canoes, or whatever anglers are willing to carry up and over the dam. Ample shoreline is also accessible for fishing.

Brown trout are wild at Muddy Guard #2 and the density of large browns was impressive when it was last surveyed in 2018. Results included 11 browns ranging from 17.4 to 28.8 inches, with the largest fish weighing 8.68 pounds. The average length of brown trout was 22.4 inches.

Game and Fish is working to improve this stocked rainbow trout fishery. Abundant longnose suckers have challenged the rainbow fishery for years through competition for aquatic insect and crustacean forage. The sucker population has declined but the body condition and growth of rainbows had not yet improved in 2018. Rainbow trout at Muddy Guard #2 ranged from 8.8 to 12.6 inches when sampled in the spring, which is not much larger than when they were stocked during the previous fall.

Game and Fish began stocking tiger trout annually here in 2016 to reduce the sucker population. Tiger trout are a sterile hybrid between brown trout and brook trout and we can control their numbers through stocking. Small tiger trout feed on aquatic insects until they reach a size where they shift to eating mostly other fish – like young suckers. It’s likely that they are growing slowly as well and looks like it will take some time for them to get on top of the sucker population.

Cross Creek Reservoir

A good fishery is just a short ATV ride and walk away. Cross Creek Reservoir, upstream of Big Horn Reservoir, offers up some good brook trout ranging in size from 8 to 11 inches. Rainbow trout and brown trout are present as well but not in as large of numbers, but some decent sizes. Rainbows were found to be around 12 inches and the few browns were between 14 and 20 inches. Put Cross Creek Reservoir on your to-do list for 2020!

Park Reservoir

This fishery has been struggling over the last 15 years due to an overpopulation of white suckers. These suckers out-compete trout for food and space, resulting in a lower quality, less healthy trout. To combat the sucker population, we have been stocking splake (a brook trout – lake trout hybrid) and lake trout. Our hope is they will eventually get big enough (takes longer at this high elevation and colder water temperatures) to prey upon the suckers. This year we found splake to range in size from 11 to 14 inches and lake trout 10 to 14 inches.

Brown and brook trout are wild in this fishery (meaning they are naturally reproducing) and are the most populous. Brown trout can get very large in this reservoir, up to 15 pounds, but generally range from 7 to 15 inches. We found the brook trout to be above average size for most Bighorn Mountain waters as they ranged from 8 to 11 inches. Our stocked rainbows are doing better than past years and are growing to larger sizes with most ranging between 11 and 15 inches.

Big Horn Reservoir

Unique opportunity awaits at Big Horn Reservoir. While technically a private inholding within the Bighorn National Forest, this reservoir is signed up in our Walk-In-Access program and is accessible to anglers. Similar to Park Reservoir, this fishery is also affected by the overabundance of white suckers, which compete with the wild brown, brook and rainbow. We introduced tiger muskie, a sterile hybrid between northern pike and muskellunge in 2017. We’ve used tiger muskie in other waters like Healy Reservoir to prey upon yellow perch and green sunfish, but this is our first time trying them at a higher elevation water in the Sheridan Region. Our hope is that they will prey upon the suckers and improve the trout fishery. In 2019 we sampled our first muskie, a 17-inch fish that was almost two pounds! A reminder to anglers, the regulation for tiger muskie is one (1) fish and fish smaller than 36 inches must be released immediately.

Twin Lakes Reservoir

Just a quick, short walk can put you on some good fishing at Twin Lakes Reservoir. The wild brook trout are plentiful and they are of decent sizes ranging from 6 to 13 inches. Twin, however, is most known for its lake trout. While most are less than 20 inches, there is always a chance at a trophy-sized fish. Over the years of sampling Twin, we have captured several lake trout between 8 and 22 pounds! Late fall is a good time to target these giants.


- WGFD -

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