An impoundment of the Wind River, the Boysen Reservoir is a 19,560-acre body of water located in Fremont County, Wyoming. The reservoir is surrounded by the Boysen State Park, which comprises more than 35,000 acres of land for activities such as camping, lounging on the beach, geocaching, picnicking, playing sports, and wildlife watching.
Often spotted around the park are deer, antelope, waterfowl, game birds, and bighorn sheep. In addition to the wildlife that can be spotted on land, the Boysen Reservoir is home to several species of fish. There are plenty of boat ramps located around the reservoir and there are some onshore fishing spots among the 77 miles of shoreline for those who want a chance at catching some game fish. Below are some of the most popular and common fish species that are found in the Boysen Reservoir.
Boysen Reservoir Fish Species
1) Walleye (Sander vitreus)
Walleye are a popular species in the Boysen Reservoir, and they can often be found in areas with submerged coverings. This species has a brownish-green body that fades to a cream belly complete with dark horizontal lines. These fish are the largest of the perch family, and they average about 11 pounds.
Walleye get their name from their big, glassy pupils, and these eyes look like this due to a reflective layer on the inner eye called the tapetum lucidum, which helps walleye see prey in times of low visibility. This layer makes walleye sensitive to bright light, however, so they often hunt for their prey, like fishes and mudpuppies, at dusk or night. In the Boysen Reservoir, the daily creel limit for walleye is six fish.
2) Sauger (Sander canadensis)
Saugers, also known as sand pike, are closely related to walleye and can be found in deeper waters than walleye are usually found. Sauger and walleye look similar; however, saugers have a few distinguishing characteristics including dark blotches on the body, scales on the cheek, and dark spots on the first dorsal fin. Saugers are also smaller than walleye, weighing in at around 1 – 5 pounds on average.
Much like the walleye, saugers also have tapetum lucidum, so they exhibit similar behaviors when hunting for prey such as fish and crustaceans. The daily creel limit for sauger in the Boysen Reservoir is two fish.
3) Yellow perch (Perca flavescens)
Yellow perch are found throughout the Boysen Reservoir because they enjoy the clear waters the reservoir has to offer. Perch can live in areas with low oxygen content; however, they will not be able to survive in waters with higher turbidity. This species is known for its golden yellow to greenish body covered in 6 – 8 dark vertical bars. These fish have yellow or green eyes and orange-red tinted fins.
Yellow perch generally grow to about 7 – 10 inches long and weigh around one pound, although this species is prone to having stunted growth in areas where food is limited. When food is abundant, adults will feed on the bottom of the water with their subterminal mouth, and they will search for items such as benthic macroinvertebrates as well as smaller fish.
4) Black crappie (Pomoxis nigromaculatus)
Black crappies are a very abundant panfish species in the Boysen Reservoir, and they can be found near areas with submerged coverings. These fish have compressed bodies and are generally a darker green on the back with dark mottling on the silvery sides. They also have 7 – 8 spines on their dorsal fins, which distinguishes them from white crappies, who have 5 – 6 spines.
This species exhibits sexual dimorphism, so the males tend to be larger and darker than the females. Black crappies typically grow to about 8 – 12 inches long and weigh 0.25 – 1 pounds. This species is generally nocturnal, so they will hunt during the night for small fishes, crustaceans, and insects.
5) White crappie (Pomoxis annularis)
White crappies are slightly less common in the Boysen Reservoir, but the best chances of finding these fish are in highly vegetated areas where the water is slightly murkier. This species has compressed bodies that are silvery olive on the back and silvery white towards the belly. These fish have dark vertical bands along the sides of their bodies, and their gill covers have spines.
During the breeding season, males will look slightly different than females because the males will develop a dark throat. White crappies average about 9 – 10 inches long and are around 2 pounds as adults. These fish generally eat smaller fishes like minnows or shad, but they will also eat insects like mayflies.
6) Burbot (Lota lota)
Burbot are the only freshwater cod species in North America, and they enjoy the cold, clear waters that can be found in areas of the Boysen Reservoir. These fish come in a variety of colors from gray to brown to olive, and they have dark mottling covering their whole body. Burbot also have very long dorsal and anal fins that almost seem to attach to the caudal fin, and their microscopic scales make them appear to be scaleless.
Burbot are relatively long-lived fish, so it takes about six or seven years for them to grow around 16 inches long and 3 – 5 pounds in weight. As juveniles, burbot mainly feed on zooplankton and insects, and adults will primarily eat other fish. In the Boysen Reservoir, there is a three-fish daily possession limit for burbot.
7) Rainbow trout (Oncorhynchus mykiss)
Rainbow trout come in two forms: freshwater resident and anadromous. Rainbow trout that reside in freshwater, like that in the Boysen Reservoir, are typically a lighter silver color with bold dark markings along the body, and they have a light pink line running laterally from head to tail. Rainbow trout typically grow between 12 – 20 inches long and weigh 1 – 4 pounds. This species is also closely related to the cutthroat trout, but unlike cutthroat trout, rainbow trout do not have basibranchial teeth.
Rainbow trout primarily feed on larvae that float through the water. Relying on this food source saves a lot of energy since they are not actively foraging, but adults will also eat other fishes, crustaceans, and worms. Rainbow trout are an incredibly popular sport fish, so this species has been introduced to every continent except for Antarctica.
8) Cutthroat trout (Oncorhynchus clarkii)
Cutthroat trout have more than 10 subspecies in varying geographic locations, and each subspecies looks slightly different from each other; however, there are characteristics that all of these subspecies share. While coloration varies among different subspecies, all cutthroat trout have red marks on their lower jaws, which is what gives the fish their name. Cutthroat trout also have teeth on the base of their tongue called basibranchial teeth.
These fish range from about 7 – 16 inches in length and weigh around 4 – 9 pounds. Cutthroat trout feed on algae, small crustaceans, and insects when they are young, and adults will feed on just about anything including other fish.
9) Brown trout (Salmo trutta)
Brown trout prefer to live in deeper areas of the Boysen Reservoir. These fish have a brown or olive green body with dark colored spots, and their undersides are tannish. Adult brown trout range from about 7 – 22 inches in length and weigh anywhere from 1 – 52 pounds. Female brown trout tend to have a larger abdomen and a smaller head compared to males. Brown trout primarily feed on invertebrates and crustaceans, but larger individuals will prey on other fishes.
Brown trout have been introduced to waters all over the world, and they are considered invasive in many areas. While they are a popular sport fish, brown trout seem to be having many negative impacts on ecosystems including the decline of other fish species, as well as the alteration of algal biomass in certain waters. The daily creel limit for brown, cutthroat, and rainbow trout combined is six fish.
10) Brook trout (Salvelinus fontinalis)
Brook trout can be found more towards the dam in the Boysen Reservoir, and they have very specific environmental conditions that need to be met in order to survive. Brook trout have a dark green or brown back that fades into silver-colored sides. They have cream-colored wavy lines along their heads and back that turn into spots on their sides, and they also have red and blue spots speckled across their body.
Brook trout can reach lengths of up to 20 inches and weigh 2 – 13 pounds on average. These fish are opportunistic feeders and will eat just about anything that finds its way into the water including insects, worms, fish, salamanders, and even small rodents! Currently, the daily creel limit for brook trout in Wyoming is 16 fish.
11) Lake trout (Salvelinus namaycush)
Lake trout are mainly found in lakes with very high concentrations of dissolved oxygen and cool, deep waters. Lake trout have a greenish-colored body that is full of cream-colored spots from the head all the way to the tail, and the lower fins are usually an orange-red color.
This species has an average length of about 20 inches and usually weighs 5 – 15 pounds, but they can get much larger as well. Lake trout are piscivores, which means they eat other fishes, but if this species has to move to deeper water in the warmer summer months to keep cool, they may have to feed entirely on zooplankton.
12) Splake (Salvelinus namaycush x Salvelinus fontinalis)
Splakes are a hybrid between male brook trout and female lake trout that have been produced in fisheries since the 1870s and regularly stocked in waters in northern North America. Splakes look almost identical to brook trout, but the main difference between the two is that splakes have a forked caudal fin, whereas brook trout have a square caudal fin.
As splakes grow very rapidly and may not be able to reproduce naturally, fisheries have been stocking splakes in water where brook trout were unsuccessful in surviving in an attempt to control populations of other sport fishes like bass. In the Boysen Reservoir, there is a six-fish daily creel limit for lake trout and splake combined, and all fish caught must be over 24 inches long.
13) Largemouth bass (Micropterus salmoides)
Largemouth bass are usually found in the Boysen Reservoir in shallower waters where there is lots of cover and vegetation. Largemouth bass get their name from their mouth, which extends past the eye, unlike smallmouth bass. Largemouth bass have olive-green bodies with dark mottling along the back and speckles along the sides.
This species has an average length of 13 inches and will generally weigh 2 – 4 pounds, although the largest largemouth ever recorded was 22 pounds and 4 ounces. Largemouths are carnivores that primarily feed on crayfish but will also eat other fishes and insects. The daily creel limit for largemouth and smallmouth bass combined is six fish.
14) Bluegill (Lepomis macrochirus)
Bluegills are a very common sunfish throughout the United States, and they can be found in shallow, vegetated areas of lakes and rivers as juveniles, but adults tend to be in deeper, vegetated waters during the day. These fish are characterized by having disk-shaped bodies with an olive green back, an orangish-yellow belly, and a black dot at the base of the dorsal fin. Bluegills get their name from the bluish hue surrounding the gill covers.
This species averages around 7.5 inches in length and weighs around half a pound as adults. These fish have very little mouths, so they will only eat smaller prey such as zooplankton, insects, worms, and snails. Bluegills are a main source of food for many larger fish species such as largemouth bass, so they have adapted to be maneuverable. For instance, this species can make very quick stops by spreading out their pectoral fins.
15) Stonecat (Noturus flavus)
Stonecats are a type of catfish species that prefer moderately flowing water and rocky substrates. These fish have long, slender bodies with tan or gray backs that fade into yellow or white bellies. They also have long adipose fins that look connected to the caudal fin, but the fins are actually separated by a small notch.
The average size for stonecats is about 3 – 5.5 inches in length, and they generally weigh less than a pound. Stonecats have barbels on their face like other catfish species, and they also have a tooth patch on the roof of their mouths with many backward-facing teeth that help them catch insect larvae, crawfish, and minnows.
16) Black bullhead (Ameiurus melas)
Black bullheads are a type of catfish that can be found in the Boysen Reservoir where the water is still and the bottom is silty; although they are incredibly tolerant to many different water conditions. These fish have black or dark olive bodies and cream-colored bellies. Black bullheads can be distinguished from other species of bullheads by a light-colored band that runs along the base of the tail.
This species grows to about 8 – 14 inches in length and weighs 1 – 2 pounds. Equipped with eight black barbels on their face, black bullheads navigate the waters to find anything they can eat including small crayfish, worms, small mollusks, crustaceans, and aquatic plants.
17) Mountain whitefish (Prosopium williamsoni)
Mountain whitefish are a coldwater species that can be found in streams and lakes with clear water, like the Boysen Reservoir. This species is characterized by its long slender body with a brown or olive back, silver sides, and white belly. These fish also have short heads with slightly pointed snouts.
Mountain whitefish generally grow to about 10 – 16 inches in length in Wyoming. This species has a very small mouth with a tooth patch on the tongue, which they use to eat plankton in the reservoir, but they can also eat some insects as well. The daily creel limit for whitefish species in the Boysen Reservoir is currently six fish.
18) Common carp (Cyprinus carpio)
Common carp, also known as European carp, are a common fish found in the Boysen Reservoir, and they prefer areas where water is warmer and still or very slow-moving. This species has a robust body with a brassy green back and white to yellow sides. They have large scales with a black dot on each and two pairs of barbels on their upper jaw. These fish have rows of pharyngeal teeth that they use to dig up aquatic plant roots to eat in addition to catching insects, crustaceans, and small mollusks.
Common carp are a non-native species to North America, and they were brought to the United States in the late 1800s because they were a wildly popular food item for immigrants who wanted to be able to continue eating them when they came to the United States.
19) River carpsucker (Carpiodes carpio)
River carpsuckers are not incredibly abundant in the Boysen Reservoir, but these fish can be found in siltier waters that are a bit warmer. This species has a brown or olive back that fades to silvery sides and a white belly. River carpsuckers also have a slightly hunched back and a protrusion coming from the middle of their bottom lip.
These fish are the largest of the carpsuckers, and they average around 12 – 18 inches in length and weigh 1 – 3 pounds. River carpsuckers tend to travel in schools, and they will search the sandy or silty lake and river bottoms for algae, protozoans, chironomids, microcrustaceans, plankton, and detritus to eat.
20) White sucker (Catostomus commersonii)
White suckers enjoy the colder, clear waters of the Boysen Reservoir. These fish have long, round bodies with dark brown or green backs, cream bellies, and clear fins. When males are breeding, they will gain a gold coloration on their backs as well as reddish stripes on their sides.
This species has a large size range, but adults typically grow to about 10 inches long and weigh about 1 – 5 pounds. White suckers have a unique mouth that is subterminal, toothless, and contains thick lips. With this mouth, they feed on the bottom of the water and suck up anything like fish, fish eggs, plants, mollusks, insects, and algae.
