Spring Patterns- “what will early ice out do?”
By Wade Watson “Kab Kid”
Walleyes spawn in spring, but “spring” in your backyard might be in February or March this season, and in April or May on these border lakes in northern Minnesota. One thing about 2024 is that spring seems to be coming early no matter where you are. Technically the first day of spring is March 19th, but most fish don’t know that. Water temperatures trigger walleyes to lay eggs in shallow gravel or rocky areas anywhere between 42°F and 50°F. Biologists have found walleyes laying eggs in Minnesota and Wisconsin, as early as March 5th and as late as May 7th. When we talk about water temperatures, remember locations across the states can vary. Most agree that spawning has specific temperature ranges, and these ideal temperatures vary by latitude. Southern walleyes prefer spawning temperatures between 48°F and 50°F, while northern states and Canadian counterparts favor temperatures between 44°F and 48°F. According to the Minnesota DNR, Male walleye move into spawning areas in early spring when the water temperature may be only a few degrees above freezing. The larger females arrive later. Spawning reaches its peak when the water temperature ranges from 42 to 50 degrees. A five-pound female deposits more than 100,000 eggs (as many as 600,000 eggs). Neither parent cares for the eggs in any way.
The surface of the eggs is very sticky, so they stick to the surface of the rocks and the gravel. Their hatching takes from five days to two weeks. Male walleyes mature faster than female walleyes; the male walleyes mature in two to four years but, the female walleyes mature in three to five years.
In the extreme Far North, if those ideal conditions don't arrive early enough, walleyes absorb their eggs and forego spawning. In the South, on the other hand, walleyes spawn successfully based on what scientists call the chill temperature hypothesis. For their eggs to develop properly, they need to spend a portion of winter in water temperatures that dip below 50°F.
Both male and female walleye will grow 3-5 inches during their first 5 to 6 years. Once they reach maturity, their growth rate slows down to about 1 to 3 inches per year. Again, remember several external and internal factors will determine their average annual growth, and growth rates between different populations and habitats can vary greatly.
This means that, on average, a 10-inch walleye is about 2 years old, while a 20-inch walleye can be aged 8 to 10. It is important to remember that female walleye grow faster than their male counterparts, which means a 20-inch walleye may be 7-8 years old if it was a female, and more like 10 years old if it were a male walleye.
Spring Walleye Migrations – Taken from In-Fisherman article by Gord Pyzer 2023
When walleye migrations begin for spawning, we find as much variation and dissimilarity in their movement patterns as during the rest of the year, although the norm probably is different than most anglers suspect. "Mature members of all self-propagating walleye populations, whether stream-spawning or lake-spawning, migrate from overwintering grounds to spawning grounds in spring," says Dr. Peter Colby, former head of the walleye research program of the Ontario Ministry of Natural Resources. "But the fish often aren't the long-distance runners many anglers believe them to be."
He confirms what most walleye anglers already know: Stream spawners migrate into creeks and rivers to spawn on rock and gravel substrates. Lake spawners move inshore to spawn on shallow, windswept rock and cobble shoals. In many waters both types of walleyes coexist, a way to ensure effective spawning.
Colby says that tagging studies indicate that most walleye populations move only a short distance. "Even in Lake Superior and Georgian Bay," he says, "a majority of spawners move no farther than three miles from their spawning grounds. Presumably, a migration of similar magnitude is undertaken to return to the spawning grounds the following spring, since evidence now suggests that mature walleyes tend to return to the same spawning grounds year after year."
He calls this repetitive migration. He points to studies where walleyes were transferred upstream in river impoundments, only to move back downstream, past dams and other barriers, to their original locations. He acknowledges that some intermingling occurs, especially in lakes and reservoirs where spawning sites lie close to one another.
Learned Spring Patterns
Minnesota biologists Donald Olsen and Dennis Schupp, and Ontario biologist Val Macins, have reinforced the research Colby draws on. These scientists suggest that the ability to home into specific spring spawning sites is an adult learned behavior, an action influenced by the water's physical layout size, shape, bottom contours, and locations of suitable lake and river spawning areas. By roaming, walleyes become familiar with the best spawning areas.
Some waters, such as the Rainy River at the south end of Lake of the Woods, the Red River at the bottom of Lake Winnipeg, the Thames River in Lake St. Clair and Lake Erie's western basin are major spawning draws. In other waters such as on Canadian Shield lakes, many smaller spawning sites exist, and spawners are more spread out.
Olsen, Schupp, and Macins believe that the more often a walleye returns to a specific spawning shoal, the more permanent the route and site become. Walleyes must learn where to go in spring. After hatching, walleye fry is at the mercy of wind and river currents; they are dispersed throughout the lake or reservoir. Depending on weather, the success of spawning can vary greatly year to year. Rapidly warming water can cause eggs to hatch prematurely. Prolonged cool weather can delay and impair hatching. A cold snap after the hatch can suppress the production of microcrustaceans that walleye fry eat. Year-class strength 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.
Walleyes develop a homing instinct to a spawning area they chose as adults. This homing mechanism, according to the three biologists, is strongest in walleyes with short migrations between summer and winter-feeding areas and spawning sites. In their words, "spawning migrations from home feeding areas likely are to the nearest spawning site, even though migrations of great distances apparently occur (in portions of some populations)."
More interesting still, the scientists suggest that the destination of a first-time spawning walleye probably is a chance occurrence. First-time spawners travel with adults like migrating geese in fall following them to spawning sites. Regardless of how they find spawning sites, walleyes appear to choose them and then home to them with greater fidelity each year of their lives.
This suggests that in lakes and reservoirs peppered with spawning shoals, the best fishing for larger walleyes likely is adjacent to those sites that are the best summer and winter areas for big fish.
Those spawning sites may not be the largest spawning areas in terms of physical size or numbers of fish they host; but on a micro basis, they're the best.
Popular opening-day spots well known for producing numbers of eating-size walleyes, meanwhile, may or may not harbor many large fish. Indeed, these sites probably are subject to fluctuations in the number of walleyes that use them. Olsen, Schupp, and Macins suggest that "If homing is strengthened by repeated migrations, populations comprised of a large proportion of older fish, rather than heavily exploited populations of younger fish, would display stronger homing tendencies."
Still, this can change over time, especially when enlightened management rules afford more protection to fish entering the egg-laying stage of their lives. Then, as more walleyes move into the adult ranks, Colby's reinforced homing mechanism kicks in and the age of the fish on a particular spawning location increase.
Smarter Walleyes
Older walleyes appear to be smarter than younger fish, which is hardly a surprise. Larger walleyes move from spawning areas in a hurry--much faster than most anglers think. "We got into a bunch of small males," is the usual opening-day refrain from frustrated walleye anglers. "The bigger fish are recuperating and refuse to bite." But according to Colby, smaller male walleyes predominate in the spring catch because males outnumber females on the spawning grounds. Males mature at least a year earlier than females, adding at least one extra year-class of them on the shoals.
Colby also says that larger female walleyes quickly vacate spawning areas in search of a deep-water refuge. They head for deeper regions, especially if soft-rayed forage like ciscoes and smelt are available. It isn't that they just quit feeding.
Younger, smaller walleyes, both male and female, often forage on perch. Perch tend to stay shallow, so smaller walleyes stay shallow, too. This isn't to suggest that large walleyes don't eat perch. They certainly do, especially in emerging weed growth during the Pre-summer and Summer Peak periods.
Small walleyes eat perch (and shiners) because these baitfish are more abundant, not just because walleyes prefer them, Colby explains. As walleyes grow bigger, however, they switch from what is most abundant to what they prefer: Soft-rayed forage like deeper-dwelling cisco, whitefish, smelt, and herring. And walleyes also function metabolically more effectively in the depths.
Wade Watson, ”Kab Kid”
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