Walleye

What it is

The walleye is a freshwater fish belonging to the perch family. Its body displays olive and gold tones on the back and sides, fading to white on the belly. Five dark saddles mark the upper flanks. The fish has large teeth and spiny dorsal fins. A key feature is its pearlescent eye, caused by a reflective layer that enhances vision in low light. This trait gives the species its common name. Walleyes differ from the similar sauger by lacking black spots on their tail fin. They typically reach lengths of around 80 centimetres, though records show individuals exceeding one metre.

Where it lives

This species inhabits waters throughout most of Canada and the northern United States. Populations exist in the Great Lakes region, the Missouri River system, and various glacial lakes. Genetic studies indicate that fish within a single watershed are distinct from those in nearby areas. However, artificial stocking programs have sometimes mixed these groups. The fish thrives in both clear and turbid waters, often preferring deeper zones during warm summer months or at night when surface light is high.

How it lives

Walleyes avoid bright sunlight and feed primarily during dawn, dusk, or cloudy periods. Their superior vision allows them to hunt effectively in murky water where prey cannot see well. Adults consume fish such as yellow perch and ciscoes, along with crayfish and leeches. Juveniles start by eating invertebrates like zooplankton before switching to a piscivorous diet after two months. They often move to shallow bars at night to feed. Predators include larger fish and birds, while human fishing pressure limits the age of many captured individuals.

Breeding and life cycle

Adults migrate to tributary streams in late winter or early spring to spawn. Eggs are laid over gravel, rocks, sand, or vegetation depending on the population. Water temperatures between six and ten degrees Celsius trigger reproduction. Females release up to half a million eggs, which stick slightly to substrates. Parents provide no care for the offspring. Embryos hatch after twelve to thirty days, absorbing yolk reserves for about a week before swimming freely and feeding on small invertebrates.

Fish and people

The walleye is a major target for recreational anglers and commercial fisheries. Fried walleye is a staple dish in Canadian cuisine and parts of the United States, particularly Minnesota. Anglers often fish at night or during windy conditions known as a 'walleye chop.' The species holds cultural significance in several regions. It serves as the official state fish for Minnesota, South Dakota, and Vermont, and the provincial fish for Manitoba and Saskatchewan. Statues of the fish stand in towns claiming the title 'Walleye Capital of the World.'

Status and threats

The species is widespread and generally considered least concern. Management agencies regulate fishing through quotas and size limits to prevent overexploitation. In some areas, walleyes are viewed as nuisance species due to their abundance, prompting research into hormonal population control. Hatcheries play a significant role in maintaining stocks, with facilities like the Garrison Dam National Fish Hatchery producing millions of fry. Conservation efforts focus on preserving genetic diversity among different watershed populations.

Relatives and look-alikes

The walleye shares its genus with the sauger, a smaller relative found in similar habitats. Historically, a blue colour variant called the blue walleye was described as a separate species, but genetic analysis confirmed it is merely a phenotypic variation of the same fish. The European zander is a close relative in the same genus but lives in Old World waters. True pickerels belong to a different family entirely, despite sharing regional names in English-speaking Canada.

Questions people ask about Walleye

Good reading and sources

• Walleye on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data