Distribution in local area:
Baptiste Lake, Fraser Lake,
Kamaniskeg Lake, Lower Paudash Lake, Rapid Lake, Salmon
Trout Lake,
Name:
Stizostedion, "pungent
throat"
vitreum, from the Latin, "glassy", referring
to the large eye. Common name from the pearlescent eye,
caused by the tapetum lucidum, a reflective layer of
pigment that helps the fish to see and feed at night
or in turbid water.
Other common names include: Blue Pike, Core, doré
(Fr), Dory, Glass-Eye, Grey Pike, Green Pike, Jack,
Jackfish, Jack Salmon, Marble-Eye, Pickerel, Pike, Pike
Perch, Sauger, Susquehanna Salmon, Walleye Pike, Wall-Eyed
Pickerel, Wall-Eyed Pike, Wall-Eyed Perch, White Eye,
Yellow Pickerel, Yellow Pike, Yellow Pike Perch, Yellow
Walleye.
Taxonomy:
Kingdom
Animalia
Phylum Chordata, animals with a spinal chord
Subphylum Vertebrata, animals with a backbone
Superclass Osteichthyes, bony fishes
Class Actinopterygii, ray-finned and spiny rayed fishes
Subclass Neopterygii
Infraclass Teleostei
Superorder Acanthopterygii,
Order Perciformes, perch-like fishes
Suborder Percoidei
Family Percidae, true perch
Genus Stizostedion, pike perch
The perch family is a large one, with about 140 species
in North America alone. The Walleye (Stizostedion vitreum)
is a close relative of the Yellow Perch (Perca flavescens),
Sauger (Stizostedion canadense), and the darters.
Description:
Largest member of the perch
family
Length:
13"-25"
Weight:
averages 1-2 lbs in most waters
occasionally exceeds 10 lbs
females grow more rapidly and attain a larger maximum
size than males
Coloration:
highly variable, depending on
habitat; usually paler with less obvious black markings
in turbid waters, more strikingly marked in clear water.
dark olive brown to yellowish gold sides, often marked
with brassy flecks
underside white
no distinct dark bars or mottlings on the sides of the
body, but instead an overall mottling of brown or black
no spots on forward dorsal fin; one large dark spot
or blotch near base on the last 2-3 spines of rearward
dorsal fin.
lower tip of the tail fin white
young usually have dark blotches across their backs
and down their sides, patterns usually absent in adults.
Body:
torpedo-shaped
dorsal fin of 19-22 rays
anal fin of 12-14 rays
lateral line of 80-89 scales
Head:
eye pearlescent, a result of
the tapetum lucidum, a reflective layer of pigment that
helps the fish to see and feed at night or in turbid
water.
strong canine teeth
cheeks sparsely scaled
Lifespan:
about 7 years, most often caught
as 1-3 lb three-year-olds
maximum 10-12 years in south to perhaps over 20 years
in the north.
Similar species:
Sauger (Stizostedion canadense)
Identification:
unlike
the sauger, the walleye lacks spots on its dusky dorsal
fin, except for a dark splotch at the rear base of the
fin, a marking the sauger does not have. The lower tip
of the walleye's tail is white, unlike the all-dark
lower lobe of the sauger.
two distinct fins on its back, the first featuring large
spines.
Habitat:
A "cool-water" species,
preferring warmer water than trout and cooler water
than bass and panfish. usually over firm bottom such
as sand, rock or gravel; occasionally near vegetation
but not in it.
The special layer in the retina of the eye tapetum ucidum,
being extremely sensitive to bright daylight intensities,
restricts feeding to twilight or dark periods. Walleye
are tolerant of a great range of environmental situations,
but appear to reach greatest abundance in large, shallow,
turbid lakes. Large streams or rivers, provided they
are deep or turbid enough to provide shelter in daylight,
are also preferred habitat of the walleye. They use
sunken trees, boulder shoals, weed beds, or thicker
layers of ice and snow as a shield from the sun.
Food:
Primarily other fish, such as
Yellow Perch (Perca flavescens), Lake Whitefish (Coregonus
clupeaformis), and minnows, as well as insects. If fish
and insects are scarce, it also consumes snails, frogs,
and small mammals.
Diet shifts rapidly, from invertebrates to fishes, as
the walleye increase in size. During the first six weeks
of life their diet consists mostly of copepods, crustaceans,
and very small fish. They can be cannibalistic, especially
if small yellow perch or other forage fish are not readily
available. Some populations, even as adults, feed amost
exclusively on emerging larval or adult mayflies for
part of the year.
Yellow perch and cyprinids are particularly favoured
when these species are present. Other food such as crayfish,
snails, frogs, mudpuppies, and rarely small mammals
may be taken, but usually only when forage fish and
insects are scarce.
Northern Pike (Esox lucius) is probably the dominant
predator of the walleye over much of its range. Northern
also an important competitor because it is the only
other major, shallow-water predator in the north. Adult
perch, other walleye, and the sauger prey on young walleye.
Many fish-eating birds and mammals also take young walleye.
The walleye's low-light vision and sensitivity to bright
light play a large role in its behavior. They usually
feed in shallow water at dawn and dusk. Walleye are
fish-eaters, preying heavily on yellow perch, which
cannot see as well as the walleye in low light and thus
are easy prey at night.
Yellow perch, sauger, and smallmouth bass are the walleye’s
main competitors for food.
Immediately after the yolk sac is absorbed, the fry
begins to feed. At first only the tiniest planktonic
organisms can be utilized, but as the fish increase
in size, cladocerans and immature aquatic insects are
consumed. Small fry are sometimes observed in schools
on the spawning grounds but soon disperse. After the
fish reach approximately 2" in length, they begin
to add small fishes, minnows, yellow perch, suckers,
and bluegill to their diet. Adult walleye consume large
quantities of fish, sometimes feeding upon them almost
entirely. Yellow perch make up a substantial part of
the walleye diet in the natural lakes. The next time
you catch a walleye, or for that matter its first cousin
a sauger, take a moment to carefully examine its eyes.
Not only are these features the origin of its common
name and a prominent part of their appearance, but their
unique physiology permits this fish to adapt into an
ecological niche that is occupied by few other species.
Walleye are perfectly adapted for capturing prey in
very low light, or even in total darkness. At the same
time in most clear waters that they occupy, they forage
most effectively at dawn and dusk when the prey fishes
have limited vision but remain active. For this reason,
walleye are termed low light condition feeders, and
fishing success is traditionally best during these periods.
Some of the most avid walleye fishermen never fish during
daytime, finding catch success best in semi- or total
darkness.
The large, unusual eyes of the walleye are designed
to help them easily find their prey.
In clear lakes the walleye often lie in contact with
the bottom, seemingly resting. In these lakes, they
usually feed from top to bottom at night. In more 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. White suckers, for example, orient
themselves in walleye schools and behave as part of
them. During the winter the walleye do not change their
habitat except to avoid strong currents.
Uses:
One of the most important game
fish in North America. Not a spectacular fighter when
hooked, but quite tasty on the table. Second only to
the Largemouth Bass (Micropterus salmoides) in popularity
in the US, it reigns supreme in Canada.
Taken commercially on the Great Lakes and in Canada.
Probably the most economically valuable species of Canada's
inland waters.
Reproduction:
Begin
moving toward spawning areas in streams and on lake
bottoms in late winter and early spring. These are usually
rocky areas in flowing water below impassible falls
and dams in rivers and streams, coarse-gravel shoals,
or along rubble shores of lakes at depths of less than
6'. Males move into spawning areas in early spring when
the water temperature may be only a few degrees above
freezing, the larger females arriving later. Spawning
peaks at water temperatures of 42º-50º F.
Spawns at night over rock, rubble, gravel and similar
substrates in rivers or windswept shallows, 1'-6' deep,
where current clears away fine sediment and will cleanse
and aerate eggs. A 5 lb female deposits more than 100,000
eggs. Neither parent cares for the eggs in any way.
Spawning success can vary greatly year to year, depending
on weather. Rapidly warming water can cause eggs to
hatch prematurely. Prolonged cool weather can delay
and impair hatching. A cold snap after hatch can suppress
production of microcrustaceans that fry eat. Year-class
presence can vary 100-fold, depending on the success
of the hatch and survival of the fry. One walleye year-class
may dominate in a lake, while walleye a year older or
a year younger are scarce.
Individual eggs lodge in rubble or gravel crevices where
they will be protected and where water can circulate,
keeping them silt free and oxygenated. No protection
is provided by the parents. Once spawning is completed,
adults return to deep water.
The number of eggs produced by individual females varies
according to body size and physical condition, but normal
fecundity ranges from 23,000 to 50,000 per pound of
fish weight. Incubation lasts 12 to 18 days, depending
upon water temperature. Under the best of conditions
5%-20% of the eggs will hatch. Cold weather, which delays
hatching, extremely heavy wind action or currents which
might wash the eggs ashore, and muddy water which coats
the eggs with silt are prime factors which decrease
hatching odds.
Upon hatching, the newborn fry is about 1/2" long
and paper thin. For several days it will drift about,
absorbing the yolk sac and gaining strength.
Eggs hatch in 12-18 days on the spawning grounds and
by 10-15 days after hatching the young have dispersed
into the upper levels of open water. By the latter part
of the summer, young-ofthe-year move toward the bottom.
Growth is fairly rapid in the south, but slower in more
northerly latitudes. Females grow more quickly than
males.
The male walleye is not territorial, and does not build
a nest. The fertilized eggs are heavier than the water
and fall into crevices in the stream or lake bottom
where they stick to stones and debris. The maximum number
of eggs released by one female has been estimated at
612,000.
The walleye is not a territorial fish at spawning time;
they usually broadcast their eggs and exercise no parental
care.
But more important in controlling populations are water
temperature, stream flow and wind at spawning time,
and interference from other species which spawn over
the walleye eggs. The major controlling factor of walleye
populations appears to be mortality during the egg and
fry stage.
Males generally mature at two to four years of age and
females at three to six years of age.
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