The walleye is widely distributed across most of Canada and the Northern United States, making it a prized catch for anglers in these regions. This species thrives in freshwater environments, including lakes, rivers, and reservoirs. Walleyes prefer clear waters with moderate temperatures and are often found in areas with rocky bottoms or submerged structures where they can seek shelter and ambush their prey.
The walleye showcases a captivating blend of colors and distinctive physical features. Its dorsal side exhibits an olive hue that gracefully transitions into a golden shade on its flanks, while the belly boasts a contrasting white color. One of the walleye's most striking attributes is its pearlescent eyes, which are equipped with a reflective tapetum lucidum. This unique adaptation allows walleyes to excel in low-light conditions, giving them a significant advantage during their hunting activities.
With a large mouth armed with numerous sharp teeth, the walleye possesses the tools necessary to capture its preferred prey. Dorsal and anal fins adorn the fish's body, providing stability and maneuverability in the water. Notably, the lower lobe of the caudal fin exhibits a distinguishing white coloration, setting it apart from its close relative, the sauger. Additionally, the sauger bears distinctive rows of black dots on its dorsals and caudal fin, which are absent or less discernible in the walleye.
Walleyes display remarkable variation across different watersheds. Fish within a particular watershed tend to exhibit genetic distinctiveness, separating them from neighboring populations. Over the past century, walleyes have been artificially propagated, either by introducing them into waters naturally lacking the species or by supplementing existing populations. While this practice has contributed to increased walleye numbers, it has also resulted in a reduction in overall genetic diversity.
The reproductive behavior of walleyes is an awe-inspiring phenomenon. Typically, male walleyes reach sexual maturity between three and four years of age, with females maturing a year later. During late winter or early spring, adults migrate to tributary streams, where they lay their eggs over gravel or rocky substrates. Although some populations may spawn on sand or vegetation, the preference for suitable spawning habitats remains consistent.
Females can produce a staggering number of eggs, with larger individuals capable of laying up to 500,000 eggs. After fertilization, the slightly adhesive eggs settle between rocks, providing them with a safe environment for incubation. The incubation period varies depending on water temperature but generally spans from 12 to 30 days. Once hatched, the free-swimming embryos spend about a week absorbing the remaining yolk before transitioning to feeding on invertebrates such as fly larvae and zooplankton.
As the walleye juveniles grow, they adopt a piscivorous diet, primarily consuming fish. Yellow perch and ciscoes are common prey items for walleyes, which often patrol bars and shoals, particularly during the nocturnal hours. The availability of crayfish, minnows, and leeches also contributes to the walleye's diverse diet throughout its life cycle.
The walleye belongs to the North American clade within the Sander genus, alongside the sauger (S. canadensis). Although a taxon called the blue walleye (S. glaucus) was initially proposed, subsequent research revealed no consistent differences between the blue and yellow walleye, rendering the blue walleye a synonym and color variant of the species. Genetic analysis supports the notion that blue and yellow walleyes are phenotypes within the same species, obviating the need for separate taxonomic classification.
The walleye holds tremendous cultural importance in various regions. In Minnesota, the walleye was designated the official state fish in 1965, reflecting its popularity among anglers and locals. Notably, three towns—Garrison, Minnesota; Baudette, Minnesota; and Garrison, North Dakota—compete for the title of the "Walleye Capital of the World," each proudly displaying a large statue of the fish. Vermont also recognizes the walleye pike as its official state warm water fish.
South Dakota bestowed the honor of official state fish upon the walleye in 1982, celebrating its native presence in the state's reservoirs and glacial lakes. Similarly, the walleye holds significance in Manitoba, where it is the official provincial fish. Winnipeg, Manitoba, considers the walleye, commonly referred to as "pickerel," a cherished local delicacy. Saskatchewan also embraces the walleye as its official fish, with this species being highly sought after for sport fishing in the region.