Lake Superior supports a diverse fish community adapted to its cold, deep waters and vast shoreline. As the largest of the Great Lakes by surface area, it contains a wide range of aquatic environments, from deep offshore waters to sheltered bays, river mouths, and connected tributaries. These conditions support both fish that are native to the Great Lakes and species introduced from other regions.
Native fish have long been an important part of Lake Superior’s aquatic ecosystem. Many are well adapted to the lake’s cold-water conditions, while others are more closely associated with shallow coastal areas, bays, and tributary systems. Some native species are widespread across the lake, whereas others occur mainly in particular parts of the basin.
Lake Superior also contains several introduced fish species. Some were deliberately brought to the Great Lakes for recreational fishing, while others arrived through accidental or unintended introductions. These fish have become established to varying degrees and now form part of the lake’s modern fish community.
The fish found in Lake Superior range from small forage species to large predators, creating a complex food web within the lake. Together, these native and introduced species form the diverse fish community found throughout Lake Superior and its connected waters.
Table of Contents
Native Fish in Lake Superior
Lake Superior’s native fish community includes species that evolved within the Great Lakes and surrounding freshwater systems. These fish are naturally adapted to the lake’s cold-water conditions and occupy a variety of habitats, from deep offshore areas to shallow bays and tributaries.
| Fish | Typical Size | Main Habitat | Primary Diet / Role |
|---|---|---|---|
| Lake Trout | 20–30 inches | Deep, cold offshore waters | Fish, especially ciscoes and smelt |
| Lake Whitefish | 17–22 inches | Deep and nearshore waters | Invertebrates and bottom-dwelling organisms |
| Lake Sturgeon | 4–6 feet | Lake bottom, bays, rivers | Insect larvae, crayfish, mollusks |
| Cisco | 10–15 inches | Nearshore and offshore waters | Zooplankton and small invertebrates |
| Northern Pike | 20–30 inches | Shallow bays, wetlands, estuaries | Fish and other small prey |
| Muskellunge | 30–40 inches | Bays, rivers, nearshore waters | Fish, including suckers |
| Walleye | 15–25 inches | Bays, rivers, coastal waters | Fish, perch, minnows, invertebrates |
| Yellow Perch | 6–10 inches | Shallow bays and nearshore areas | Zooplankton, insects, small fish |
| Burbot | 15–25 inches | Cold, deep lake bottom | Fish, crayfish, insect larvae |
| Suckers | 12–24 inches | Bays, rivers, tributaries | Insects, crustaceans, mollusks, algae |
Lake Trout
The lake trout (Salvelinus namaycush) is one of the most important native fish in Lake Superior and one of its largest naturally occurring species. Adults commonly measure around 20 to 30 inches and weigh several pounds, although much larger fish are found in the lake. Exceptional lake trout can exceed 4 feet in length and 60 pounds, with Michigan’s Lake Superior state record reaching 61.5 pounds and 49 inches.
Lake trout have a streamlined, elongated body with a deeply forked tail and a mottled pattern of gray, olive, or brown across the back and sides. Their coloration can vary depending on habitat and the form of lake trout, but their pale spots and distinctive adipose fin help distinguish them from other trout and salmon found in Lake Superior.
They are especially well adapted to Lake Superior’s cold, deep, well-oxygenated waters. Lake trout can occupy deep offshore areas where water temperatures remain suitable even during warmer months, although they may move into shallower water at certain times of the year. Some forms, including the deepwater siscowet, are particularly associated with the lake’s deepest habitats.
Young lake trout feed largely on zooplankton and aquatic invertebrates before becoming increasingly predatory as they grow. Larger individuals feed heavily on fish such as ciscoes and rainbow smelt, making lake trout an important top predator in Lake Superior’s native fish community. Their slow growth and exceptionally long lifespan also allow some individuals to remain in the lake for several decades.
Lake Whitefish
The lake whitefish (Coregonus clupeaformis) is a native cold-water fish and one of the most abundant fish in Lake Superior. Adults commonly reach about 17 to 22 inches in length and weigh around 2 to 5 pounds, although larger individuals can exceed these measurements. Their slender, silvery body, small head, and slightly downturned mouth are well suited to feeding near the lake bottom.
Lake whitefish are found mainly in cool, deeper waters, but they can move into shallower areas and nearshore habitats depending on the season. They are particularly associated with rocky or sandy lake bottoms where they can search for small aquatic organisms.
Their diet consists largely of aquatic insect larvae, small crustaceans, mollusks, and other bottom-dwelling invertebrates. Young whitefish rely more heavily on small planktonic organisms, while adults consume larger prey from the lakebed. Lake whitefish are also an important food source for larger predatory fish in Lake Superior.
Because of their abundance and broad distribution, lake whitefish have long been an important commercial and recreational fish in the Great Lakes. Their populations contribute significantly to both the lake’s food web and its fisheries.
Lake Sturgeon
The lake sturgeon (Acipenser fulvescens) is one of the largest native fish in Lake Superior and one of the most distinctive species in the lake. Adults commonly reach 4 to 6 feet in length and weigh around 30 to 80 pounds, although exceptional individuals can become much larger. The largest authenticated lake sturgeon recorded from Ontario waters of Lake Superior was a 310-pound fish nearly 8 feet long, caught in Batchawana Bay in 1922.
Lake sturgeon have a long, cylindrical body covered with rows of bony plates, a pointed snout, and four barbels hanging beneath the mouth. Their appearance is quite different from that of trout and other streamlined fish in Lake Superior. They are also extremely long-lived and grow slowly, with some individuals surviving for many decades.
Unlike many large fish that actively pursue prey, lake sturgeon spend much of their time near the lake bottom. Their sensitive barbels help them locate food in dark or murky water. They feed on insect larvae, crayfish, small crustaceans, mollusks, and other organisms living on or near the lakebed.
In Lake Superior, lake sturgeon use the main lake as well as bays, river mouths, and tributaries. Adults move into suitable rivers to spawn, making connected waterways particularly important during their life cycle. Their combination of enormous potential size, longevity, and distinctive appearance makes them one of Lake Superior’s most notable native fish.
Cisco
The cisco (Coregonus artedi), also called lake herring, is a native cold-water fish and an important forage species in Lake Superior. Adults commonly grow to about 10 to 15 inches and weigh roughly 0.5 to 1.5 pounds, although larger individuals can reach around 20 inches and several pounds. Their slender, silvery body and deeply forked tail help them move efficiently through open water.
Cisco are found across much of Lake Superior, from nearshore waters to deeper offshore areas, depending on season and local conditions. They are well adapted to the lake’s cold water and can form large concentrations where food is abundant.
Their diet consists mainly of zooplankton and small aquatic invertebrates. As an important forage fish, cisco are also preyed upon by larger species, particularly lake trout and other predatory fish. This makes them an important link between small aquatic organisms and larger fish in Lake Superior.
Cisco have historically supported commercial fisheries in the Great Lakes and remain an important part of Lake Superior’s native fish community. Their abundance provides a major food source for larger fish and helps sustain the lake’s broader aquatic food web.
Northern Pike
The northern pike (Esox lucius) is a native freshwater predator found in Lake Superior, particularly in areas with suitable shallow-water habitat. Adults commonly measure around 20 to 30 inches and weigh roughly 2 to 8 pounds, while larger trophy fish can reach 40 inches or more and weigh well over 10 pounds. Their elongated, torpedo-shaped body, pointed snout, and large mouth filled with sharp teeth make them easy to recognize.
Northern pike are most often associated with shallow bays, wetlands, river mouths, and nearshore areas where aquatic vegetation and submerged structures provide cover. Unlike lake trout, they are not primarily a deep-water fish and are more closely tied to protected areas with warmer, shallower water.
They are aggressive ambush predators that feed mainly on fish. Larger northern pike may also take frogs, crayfish, and other suitable prey. They use vegetation and other cover to remain concealed before making a rapid strike at passing prey.
Within the Lake Superior basin, northern pike are particularly associated with connected waters and protected coastal areas. Populations occur in places such as the St. Louis River Estuary and Chequamegon Bay, although their abundance varies considerably between different parts of the lake.
Muskellunge
The muskellunge (Esox masquinongy), commonly called the musky, is a large native predatory fish found in parts of the Lake Superior basin. It has a long, muscular body, broad head, pointed snout, and large mouth lined with sharp teeth. Muskellunge commonly grow to around 30 to 40 inches, while larger individuals can exceed 5 feet and weigh more than 30 pounds. Much larger fish are possible for the species elsewhere in its range, although those records should not be treated as Lake Superior records.
In Lake Superior, muskellunge are relatively localized compared with more widespread native fish. They are mainly associated with shallow bays, nearshore waters, river mouths, and connected rivers, where vegetation, submerged timber, rocks, and other structures provide cover.
Muskellunge are ambush predators that primarily eat fish. They often remain concealed near cover and use their speed to strike passing prey. Their diet can include suckers and other available fish, with larger muskellunge capable of taking relatively large prey.
Within the Lake Superior basin, established populations are particularly associated with connected waters such as the St. Louis River system. Their limited distribution and large size make muskellunge one of the more notable native predators found around Lake Superior.
Walleye
The walleye (Sander vitreus) is a native freshwater fish found in parts of the Lake Superior basin, particularly in bays, nearshore waters, river mouths, and tributary systems. Adults commonly measure around 15 to 25 inches and weigh about 1 to 5 pounds, although larger individuals can exceed 30 inches and weigh more than 10 pounds. Their olive-gold body, white belly, and distinctive large, glassy eyes make them relatively easy to identify.
Walleye are especially well suited to low-light conditions. Their large eyes contain a reflective layer called the tapetum lucidum, which improves their ability to see in dim water. They often become more active around dusk, dawn, and during overcast conditions, when they can use their excellent vision to locate prey.
Their diet consists mainly of smaller fish, yellow perch, minnows, and aquatic invertebrates. Young walleye feed heavily on plankton and small invertebrates before shifting toward fish as they grow. Larger individuals can become effective predators in the shallow and moderately deep waters they inhabit.
In Lake Superior, walleye are more closely associated with protected coastal areas and connected rivers than with the deepest offshore waters. They are also found in tributary systems where suitable spawning habitat is available, making the lake’s rivers and bays important parts of their life cycle.
Yellow Perch
The yellow perch (Perca flavescens) is a native freshwater fish found in Lake Superior, particularly around nearshore waters, bays, and sheltered areas. Adults commonly reach 6 to 10 inches in length and weigh about 0.2 to 0.5 pounds, although larger fish can approach 15 inches and weigh around a pound or more. They have a slender, yellow to golden body marked by several dark vertical bands, along with two dorsal fins.
Yellow perch are generally found in relatively shallow water compared with species such as lake trout. They may move between nearshore areas and deeper water as conditions change, and they often gather in groups where suitable food and habitat are available.
Their diet changes as they grow. Young perch feed mainly on zooplankton and small aquatic invertebrates, while larger individuals consume insect larvae, crayfish, and small fish. Yellow perch are also an important forage fish for larger predators in Lake Superior, including lake trout and northern pike.
Although yellow perch are not among the largest fish in the lake, they are an important part of its native fish community. Their abundance in suitable nearshore habitats and their role as both predator and prey make them an important link within Lake Superior’s aquatic food web.
Burbot
The burbot (Lota lota) is a native freshwater fish found in Lake Superior and is the only freshwater member of the cod family. It has a long, slender body, a broad flattened head, a large mouth, and a single barbel beneath its chin. Adults commonly reach about 15 to 25 inches in length and weigh around 1 to 5 pounds, although larger individuals can exceed 30 inches and weigh more than 10 pounds.
Burbot are well adapted to the cold, deep waters of Lake Superior. They are more active in colder conditions than many other freshwater fish and can be found along rocky or sandy lake bottoms. During winter, they may move into shallower areas and tributaries to spawn.
They are primarily bottom-feeding predators, eating fish, crayfish, insect larvae, and other aquatic organisms. Larger burbot consume more fish, including small lake trout and other available prey. Their feeding activity is often greatest at night and during the colder months.
Burbot are also an important part of Lake Superior’s native fish community. Although they are less well known than lake trout or lake sturgeon, their ability to thrive in cold, deep water gives them a distinctive ecological role in the lake.
Suckers
Suckers are a group of native freshwater fish found in Lake Superior and its connected waters. Several species occur in the Lake Superior basin, including white sucker, longnose sucker, and redhorse species. They generally have elongated bodies, fleshy lips, and downward-facing mouths adapted for feeding along the bottom. Depending on the species, adults commonly range from about 12 to 24 inches and can weigh several pounds.
Suckers occupy a variety of habitats, including nearshore areas, bays, river mouths, and tributaries. Many move into rivers and streams during spawning, while others spend much of their lives in lakes and larger waterways. Their ability to use both lake and river environments makes them a common component of the Lake Superior basin.
Most suckers feed close to the bottom, consuming aquatic insect larvae, crustaceans, mollusks, algae, and other small organisms. Their feeding helps move nutrients through aquatic ecosystems, while the fish themselves provide food for larger predators.
Although suckers are generally less prominent in sport fishing than species such as lake trout or walleye, they are an important part of Lake Superior’s native fish community. Their abundance in suitable habitats also makes them a useful source of prey for larger predatory fish.
Introduced Fish in Lake Superior
Lake Superior also contains several fish species that are not native to the Great Lakes. Some were intentionally introduced to support recreational fisheries, while others entered the Great Lakes through unintended pathways. These introduced species have become established to different degrees and now form part of the lake’s fish community.
| Fish | Typical Size | Main Habitat | Primary Diet / Role |
|---|---|---|---|
| Rainbow Smelt | 6–10 inches | Nearshore and offshore waters | Zooplankton, insects, small fish |
| Chinook Salmon | 24–36 inches | Open and deep lake waters | Forage fish |
| Coho Salmon | 20–30 inches | Open and nearshore waters | Small fish and aquatic organisms |
| Brown Trout | 15–25 inches | Nearshore waters and tributaries | Insects, minnows, small fish |
| Rainbow Trout | 15–25 inches | Cold nearshore waters and tributaries | Insects, crayfish, small fish |
Rainbow Smelt
The rainbow smelt (Osmerus mordax) is an introduced fish that became established in the Great Lakes, including Lake Superior. It is a relatively small, slender fish, typically measuring about 6 to 10 inches and weighing less than 0.5 pounds. Its body is silvery with a slightly translucent appearance, while the back can range from greenish to bluish. The fish has a pointed head and a small mouth suited to feeding on small aquatic prey.
Rainbow smelt can be found in both nearshore and offshore waters of Lake Superior. They tolerate the lake’s cold conditions and often form large schools, particularly where food is abundant. During spawning, they move into tributaries and other suitable shallow-water areas, sometimes gathering in very large numbers.
Their diet consists mainly of zooplankton, aquatic insects, and small fish. As they grow, they become increasingly predatory and may consume smaller fish, including young ciscoes and other forage species. Rainbow smelt are also an important food source for larger native predators such as lake trout.
The introduction of rainbow smelt had a significant effect on the Great Lakes fish community because they became an abundant forage fish. In Lake Superior, they provide a substantial food source for predatory fish and have become an established part of the lake’s modern food web.
Chinook Salmon
The Chinook salmon (Oncorhynchus tshawytscha), also called king salmon, is an introduced Pacific salmon that has become established in Lake Superior. It is the largest of the Pacific salmon introduced into the Great Lakes. Adults commonly measure about 24 to 36 inches and weigh 8 to 20 pounds, although larger individuals can exceed 30 pounds. They have a streamlined, muscular body, dark back, silvery sides, and a relatively large mouth with a prominent jaw.
Chinook salmon spend much of their adult lives in the open waters and deeper areas of Lake Superior, where they can pursue schools of forage fish. They also move into tributaries during their spawning migration, with suitable rivers and streams providing important spawning habitat.
They are highly predatory fish that feed mainly on small fish, particularly alewives, rainbow smelt, and other available forage species. Their shift to a fish-based diet as they mature allows them to grow rapidly and makes them an important predator in Lake Superior’s food web.
Chinook salmon were introduced primarily to develop a sport fishery and have become one of the more sought-after salmon in the Great Lakes. Their presence also links Lake Superior’s introduced fish community with its native predators, as larger lake trout and other predatory fish compete with them for forage fish.
Coho Salmon
The coho salmon (Oncorhynchus kisutch) is an introduced Pacific salmon that has become established in Lake Superior. Adults commonly reach about 20 to 30 inches in length and weigh around 5 to 12 pounds, although larger fish can occur. They have a streamlined body with silvery sides, a dark back, and small black spots, while mature fish develop darker coloration and a reddish tone during the spawning period.
Coho salmon spend much of their adult lives in the open and nearshore waters of Lake Superior, where they follow concentrations of forage fish. Like other salmon, they migrate into suitable tributaries to spawn, making connected rivers and streams an important part of their life cycle.
Young coho salmon feed on aquatic insects, zooplankton, and other small organisms, gradually shifting toward a diet dominated by fish as they grow. Adults are active predators and consume smaller fish, including rainbow smelt and other available forage species.
Coho salmon were introduced into the Great Lakes to develop recreational fisheries and have become part of Lake Superior’s modern fish community. They also serve as predators on smaller fish and are themselves part of the broader food supply available to larger predatory species in the lake.
Brown Trout
The brown trout (Salmo trutta) is an introduced trout species that has become established in Lake Superior. Adults commonly measure about 15 to 25 inches and weigh around 1 to 6 pounds, although larger individuals can exceed 30 inches and weigh more than 10 pounds. Their body is typically brownish or golden with dark spots, often accompanied by smaller reddish spots along the sides. Their coloration can vary considerably depending on habitat and age.
Brown trout are found in nearshore waters, bays, rocky areas, and tributaries of Lake Superior. They can tolerate a wider range of conditions than some other cold-water trout and often use rivers and streams during spawning. Adults may move between the lake and tributaries depending on feeding and spawning conditions.
Their diet changes as they grow. Young brown trout feed mainly on aquatic insects and other small invertebrates, while larger fish increasingly consume minnows, smelt, and other small fish. This shift allows adult brown trout to function as active predators within the lake’s nearshore and tributary environments.
Brown trout were introduced to the Great Lakes to provide additional sport-fishing opportunities and have established populations in suitable areas. In Lake Superior, they are generally less widespread than lake trout but remain an important introduced predator, particularly around tributaries and productive coastal habitats.
Rainbow Trout
The rainbow trout (Oncorhynchus mykiss), including the migratory form commonly known as steelhead, is an introduced Pacific trout that has become established in parts of Lake Superior and its connected waters. Adults commonly measure about 15 to 25 inches and weigh around 1 to 5 pounds, although larger individuals can exceed 30 inches and weigh more than 10 pounds. They are recognized by their silvery body, dark spots, and the characteristic pink or reddish stripe running along each side.
Rainbow trout are found mainly in cold nearshore waters, tributaries, and river mouths around Lake Superior. Some populations spend much of their lives in the lake before moving into tributaries to spawn, while others remain more closely associated with streams and coastal areas. Their preference for cool, well-oxygenated water limits them mainly to suitable habitats.
Young rainbow trout feed largely on aquatic insects, zooplankton, and other small invertebrates. As they grow, their diet can include crayfish, minnows, and other small fish. Adult rainbow trout therefore occupy a higher position in the food web and compete with other trout and salmon for both habitat and prey.
Rainbow trout were introduced to the Great Lakes primarily to expand recreational fishing opportunities. In Lake Superior, they are an established part of the introduced fish community and are particularly valued by anglers because of their fighting ability and tendency to use both lake and tributary habitats.