Walleye Fish Guide: Biology, Habitat - FishOnTips (2024)

As an ichthyologist, I have always been captivated by the remarkable diversity and adaptability of fish in aquatic ecosystems around the world. Walleye (Sander vitreus), a unique and fascinating species, is no exception to this rule.

Known for its extraordinary eyesight and distinctive appearance, the walleye has managed to capture the attention of both scientists and anglers alike. In this article, we will delve into the world of the walleye, exploring its biology, behavior, and ecological significance, as well as its importance as a recreational and commercial fish.

By gaining a deeper understanding of this enigmatic species, we hope to appreciate its vital role in maintaining the balance of freshwater ecosystems and to foster a sense of stewardship for the protection and preservation of walleye populations.

Habitat of Walleye

Walleye (Sander vitreus) inhabit a diverse range of freshwater environments across North America. They are predominantly found in the Great Lakes region, as well as in numerous rivers, reservoirs, and lakes throughout Canada and the United States. Walleye can be found as far north as the Arctic watersheds and as far south as the Mississippi River Basin.

Their preferred habitat consists of cool, clean, and moderately deep waters with a mix of rocky and sandy substrates. Walleye tend to avoid areas with heavy vegetation, instead favoring areas with underwater structures like drop-offs, rock piles, or submerged logs that provide them with shelter and opportunities for ambush.

Walleye are also known for their sensitivity to light, which is a significant factor in their habitat selection. Their large, reflective eyes allow them to see well in low-light conditions, giving them an advantage when hunting prey. As a result, they often inhabit dimly lit or turbid waters and are more active during dawn, dusk, or overcast conditions when light levels are low. In some cases, they may even venture into shallow waters at night to feed.

Seasonal and temperature-related migration patterns also influence the walleye’s habitat choices. During the spring and fall, they tend to occupy shallower waters for spawning and feeding. In the summer and winter months, they move to deeper, cooler waters to escape extreme temperatures and find suitable food sources. In large lakes or reservoirs, walleye may travel significant distances during these seasonal migrations, making them a highly adaptable and mobile species.

Walleye life cycle

The life cycle of the walleye (Sander vitreus) can be divided into several stages, each marked by distinct growth and behavioral changes. Here, we will outline the major phases in the walleye’s life cycle, from egg to adult.

1. Spawning: Walleye typically spawn during the spring months, when water temperatures reach around 42-50°F (6-10°C). Males arrive at the spawning grounds first, followed by females. Spawning generally takes place in shallow waters with a rocky or gravel substrate, often near the shoreline or in tributaries. Females release thousands of eggs, which are then fertilized by males in a process called external fertilization.
2. Egg incubation: After fertilization, walleye eggs adhere to rocks, gravel, or vegetation and incubate for 1-3 weeks, depending on water temperature. During this time, the developing embryos are vulnerable to predation, siltation, and changes in water conditions.
3. Hatching and larval stage: Once the eggs hatch, the resulting larvae are tiny, translucent, and lack a functional mouth or digestive system. They survive on their yolk sac for nourishment during this stage, which lasts for about 1-2 weeks. As they develop, the larvae begin to swim and feed on zooplankton and other small aquatic organisms.
4. Fry and juvenile stage: After absorbing their yolk sac, the larvae transform into fry, acquiring a more fish-like appearance. During this stage, they continue to feed on zooplankton and gradually transition to a diet of small invertebrates and fish. As they grow, the fry become juveniles, exhibiting the characteristic coloration and body shape of adult walleye.
5. Adult stage: Upon reaching sexual maturity at 2-4 years of age (varies by population and environmental factors), walleye enter the adult stage of their life cycle. Adult walleye are predatory fish, feeding primarily on other fish, such as yellow perch and ciscoes, as well as invertebrates like crayfish. They can live up to 10-20 years, with some individuals reaching even older ages in favorable conditions.

Throughout their lives, walleye face numerous threats, including predation, habitat loss, pollution, and overfishing. Conservation efforts, such as habitat restoration, catch-and-release fishing, and appropriate fishing regulations, are essential to maintain healthy walleye populations and ensure the sustainability of this ecologically and economically significant species.

What Walleye eat

Walleye (Sander vitreus) are opportunistic predators with a diverse diet that changes as they grow and mature. Their excellent vision, particularly in low-light conditions, makes them efficient hunters, able to locate and catch their prey with remarkable precision. Here is an overview of the main food sources for walleye at different stages of their lives:

1. Larval stage: During the larval stage, walleye primarily feed on microscopic zooplankton such as copepods and cladocerans. At this stage, they are still developing their digestive systems and hunting abilities.
2. Fry and juvenile stage: As walleye grow into fry and juveniles, their diet expands to include larger zooplankton, as well as small aquatic insects and other invertebrates like mayflies, midges, and freshwater shrimp. They also begin to prey on smaller fish species, such as minnows and young perch.
3. Adult stage: Adult walleye are primarily piscivorous, meaning they predominantly feed on other fish. Their preferred prey includes species like yellow perch, ciscoes (also known as lake herring), shiners, and smaller individuals of their own species. In addition to fish, adult walleye also consume invertebrates such as crayfish, large insects, and even snails, depending on prey availability in their habitat.

Walleye are highly adaptable predators, capable of adjusting their diet based on the availability of food resources in their environment. This adaptability contributes to their success as a species and allows them to thrive in a wide range of freshwater ecosystems across North America.

Walleye lifespan

The lifespan of walleye (Sander vitreus) can vary depending on factors such as environmental conditions, food availability, and predation pressure. In general, walleye can live anywhere from 10 to 20 years, with some individuals reaching even older ages under favorable conditions.

Sexual maturity in walleye typically occurs between 2 to 4 years of age, although this can vary based on factors like population density and growth rates. Once mature, walleye have a relatively high annual survival rate, which contributes to their relatively long lifespans.

It is important to note that human-induced factors, such as overfishing, habitat loss, and pollution, can have a significant impact on walleye populations and may affect their average lifespan. Conservation measures, such as the implementation of fishing regulations, habitat restoration, and pollution control, are essential to support healthy walleye populations and maintain the sustainability of this important fish species.

Walleye size and weight

The size and weight of walleye (Sander vitreus) can vary depending on factors like age, sex, and environmental conditions. However, they generally exhibit a moderate size and streamlined body shape well-suited for their predatory lifestyle.

Adult walleye typically range in length from 12 to 30 inches (30 to 76 centimeters) and can weigh between 1 and 10 pounds (0.45 to 4.5 kilograms). Males tend to be smaller than females, with females usually growing larger and faster.

It is not uncommon for walleye in some populations to exceed these average sizes. Trophy-sized walleye, which are particularly sought after by anglers, can reach lengths of over 30 inches (76 centimeters) and weigh more than 10 pounds (4.5 kilograms). The largest recorded walleye was caught in 1960 in Tennessee, weighing 25 pounds (11.34 kilograms) and measuring 41 inches (104 centimeters) in length.

Several factors influence the growth rate and ultimate size of walleye, including food availability, water temperature, population density, and genetics. For example, walleye living in large, nutrient-rich bodies of water with abundant prey resources may grow faster and larger than those in smaller, less productive ecosystems.

Here is a table that provides a general overview of the age, weight, and size of walleye at different stages of their lives. Please note that these values are approximate, as various factors such as environmental conditions, food availability, and genetics can influence the growth and development of individual walleye.

This table should be used as a rough guideline, and individual walleye may exhibit different growth rates and sizes depending on their specific circ*mstances. Additionally, trophy-sized walleye can exceed these values, reaching lengths of over 30 inches (76 centimeters) and weights of more than 10 pounds (4.5 kilograms).