Walleye (Stizostedion vitreum)
The walleye is the largest member of the Percidae family of perch in North America and a close relative of the sauger. A popular freshwater sportfish, the walleye is relatively abundant in many waters, grows to large sizes, and is renowned for its delicious, sweet, and fine-textured meat.
Identification
The walleye has a slender and cylindrical body with a tapered head. Its first dorsal fin has needle-sharp spiny rays and is separated from the soft-rayed second dorsal fin. The cheeks are sparsely scaled, the gill covers are sharp, and the teeth are sharp. When handling the fish, anglers must take care around the teeth, the gill covers, and the spiny dorsal fin to avoid cuts and stab wounds.The walleye has a dark green back, golden yellow sides, and a white belly. The lower lobe of the caudal fin is white, and there is a large black blotch at the rear base of the spinous first dorsal fin. Color is highly variable, depending on habitat, with golden color characteristics in many populations. Typically, fish in turbid or off-color waters are paler, with less obvious black markings; clear waters produce more definitively marked specimens.
Perhaps the most prominent feature of a walleye is its large, white, glossy eyes. The special reflective layer in the retina of the eye is a characteristic known as tapetum lucidum; it gathers light that enters the eye, making it extremely sensitive to bright daylight intensities but conducive to nocturnal vision.
Size
The size of walleye varies with their environment, but anglers commonly encounter fish in the 10- to 18-inch range and weighing about 1 to 3 pounds. Some waters support fish that are larger on average, and it is not uncommon to catch walleye exceeding 5 pounds in many places. The all-tackle world record is a 25-pounder caught in Old Hickory Lake, Tennessee, in 1960.Life history/Behavior
Spawning occurs in the spring or the early summer, depending on latitude and water temperature. Normally, spawning begins shortly after the ice breaks up in lakes that freeze; water temperature is usually in the mid-40s, but spawning may occur at a range between 38° and 50°F.The males move to the spawning grounds first. These are usually rocky areas in flowing water below impassable falls and dams in rivers and streams, coarse-gravel shoals, or (least common) along rubble shores of lakes at depths of less than 6 feet. Spawning takes place at night, in groups of one large female and one or two smaller males or two females and numerous males. The male walleye is not territorial and does not build a nest.
In clear lakes, walleye often lie in contact with the bottom during the daytime, seemingly resting. In these lakes, they usually feed from top to bottom at night. In turbid water, they are more active during the day, swimming slowly in schools close to the bottom.
Walleye frequently are associated with other species, such as yellow perch, northern pike, white suckers, and smallmouth bass. During the winter, walleye do not change their habitat except to avoid strong currents. In large water bodies, they will orient to open water in schools that coincide with the presence of baitfish, especially alewives, but also shad and perch.
Food and feeding habits
The walleye can be a voracious feeder and primarily consumes other fish. The wide diet includes alewives, smelt, shad, cisco, shiners, sculpin, suckers, minnows, darters, perch, and crayfish, as well as many other items. Their diet shifts rapidly from invertebrates to fish as walleye increase in size.Some populations, even as adults, feed almost exclusively on emerging larval or adult mayflies for part of the year. The relative amounts of the various species of fish that walleye feed on apparently are determined by their availability. Yellow perch and cyprinids are particularly favored when these species are present.
Other Names
pickerel, yellow pickerel, walleyed pike, yellow walleye, jack salmon, jack, pike-perch, walleyed pikeperch, pike, gray pike, green pike, ’eye, marbleye, glass-eye; French: doré.Distribution
The walleye is widely distributed in North America. Its native range in the north extended from Great Bear Lake in the Northwest Territories easterly to James Bay and the Gulf of St. Lawrence. In the east it extended southward along the Allegheny Mountains to Georgia and Gulf Coast drainages in Mississippi and Alabama.In the west it extended from Saskatchewan throughout the Dakotas to Arkansas. Through some natural expansion and extensive introduction, the range has been extended eastward to Atlantic coast drainages from Vermont to South Carolina and westward to all western states except California, as well as to southern Alberta and British Columbia.
Habitat
Walleye are tolerant of a great range of environmental situations but seem to do best in the open water of large lakes and reservoirs, as well as the pools of large rivers. They inhabit many smaller bodies of water but are not typically prolific in the most turbid environs, preferring somewhat clearer water than their sauger cousins.Gravel, rock, and firm sand bottoms are preferred, and they may associate with various weed cover; they will also use sunken trees, standing timber, boulder shoals, and reefs as cover and foraging sites. Although they can survive temperature extremes from 32° to 90°F, they prefer waters with a maximum temperature of roughly 77° and are commonly associated with 65° to 75° water in summer.
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