A walleye is also a
North American freshwater
fish species. Its
scientific name is
Stizostedion vitreum, and is a member of the
family Percidae. It is a warmwater species (optimal temperature is around 14
oC) and is highly prized by
anglers. It is a top predator (
tertiary consumer), and will consumer practically any smaller fish that it can manipulate in its
mouth.
There are actually two subspecies of walleye in North American. The first is the most common, Stizostedion vitreum vitreum and is a very abundant. The second subspecies is Stizostedion vitreum glaucum which was moderately abundant in a number of systems, but has been nearly globally extirpated by both over-fishing and as a result of exotics. It's closest relative is the zander, a European species (Stizostedion lucioperca).
Walleye exhibit strong sexual dimorphism. Males tend to mature at a relatively early age (3-6 years) and small size, and rarely reach sizes above 50 cm. Females mature much later, and can grow to measure over 75 cm (10 pounds or more). They are fished heavily in the Great Lakes and a number of larger systems in Canada and the United States by commercial interests. Its value to the both commercial fisheries is in the tens of millons of dollars each year.