Every serious lure ever made for pike and muskies falls somewhere within their prey-size spectrums. Muskie anglers like bigger baits because they know these baits often select for bigger fish. Pike anglers lay out a smaller fly because they know a big gator will ravage it. But when you see a muskie at boatside spit up a half dozen or so 2-inch perch, or a pike with the tail of a 2-pound sucker in its throat, it leaves you wondering if there’s more reason to work through size, when it’s practical, in the range of presentation options for both species.
As predators like pike and muskies get larger, the average size of prey in their diet increases. But what makes this relationship part of a larger story is that the range in prey size consumed also widens considerably with predator size. While the upper limit to what can be eaten rises, it’s common for smaller items to be retained in the diet of larger fish. What forms is a wedge-shaped relationship between predator size and prey size, with a level floor, a rising ceiling, and data points scattered from top to bottom (see “The Wedge,” which follows).
The Ceiling
Mouth gape—the opening between stretched jaws—sets the limit on the maximum prey size that can eaten, and prey-body depth, or girth, is the primary constraining factor. One study, however, proves that pike are capable of swallowing fish even larger than indicated by their gape size, suggesting it’s possible that the fish’s jaws can stretch even farther, or that prey is compressed and distorted while it’s being mouthed. Sometimes fish are overly optimistic. Occasionally we receive photos like the one here, of a fish meeting its demise while trying to eat something too large.
Research on the largest prey sizes capable of being eaten by pike and muskies has been limited to smaller fish in laboratory experiments. But diet studies on larger fish in natural systems should provide a good idea of their top-end potential, particularly when large sample sizes are collected across a number of lakes and prey communities.
A University of Wisconsin study by Michael Bozek, Thomas Burri, and Richard Frie included food-habits data for over 1,000 muskies captured from 34 Wisconsin lakes. Prey fish averaged 20 percent of muskie length and ranged from 6 to as high as 47 percent. Wisconsin DNR biologists Terry Margenau, Paul Rasmussen, and Jeffrey Kampa reported diets of over 600 pike from 19 lakes. Most preyfish were less than 30 percent of pike length, but some exceeded 50 percent in cases of cannibalism. These studies suggest that for pike and muskies, around 50 percent is a reasonable upper limit to prey size.
The Big Frontier
Theoretically, predators should prefer large prey because of the high nutritional return it can provide. Big pike and muskies often do key on hefty and high-energy species like ciscoes, suckers, whitefish, and carp. But a predator doesn’t think about how to optimally forage; over time, prey and predators overlap, resulting in feeding successes and failures, which leads learning and a pattern of foraging. Feeding on smaller, more abundant baitfish that are easier to catch can be just as profitable.
The current hot trend in muskie fishing is throwing larger-than-ever baits that test big muskies as well as an angler’s stamina and gear. Super Magnum Bull Dawgs, Super Model Double Cowgirls, outsized Jakes, and other lures are defining a new size-class from a foot long to around 15 inches. They’re working uncharted territory of the muskie wedge—up to about the 75th percentile of potential prey size for a 48- to 50-inch muskie—and are proving successful for big fish on a number of famed muskie factories.
