Minnesota may be known as the walleye state, but the truth is, the northern pike is most widespread game fish. In fact, with its abundance of marshy lakes and streams, Minnesota has as much or more northern pike habitat than any other state.
Good habitat is the key to producing northern pike. Given relatively clean water, adequate forage, and abundant shoreline marshes and wetlands for spawning; northern pike will proliferate without further help.
Many northern pike spawning areas have been lost to drainage, dredging and shoreline development. They are destroyed by the farmer who drains a seasonally flooded wetland adjoining a stream or lake, and by the cabin owner who kills the cattails along the shore of a shallow bay. These areas must be protected through shore land regulations that prevent draining, filling and other destruction of shoreline wetlands. Also important are regulations that prevent wholesale removal of the shallow-water aquatic weeds that provide cover to young northern pike and their prey.
Where northern pike spawning areas are lacking, a fish manager can create habitat by building a low dam to flood low-lying land near a lake. The area fills with spring runoff, the northern pike spawn and the fry grow to fingerlings. They then escape or, if there is a barrier between the lake and spawning area, are released to the main body of water.
Northern pike stocking isn't often undertaken on a large scale and is easily overdone. Research has shown that in a lake with a naturally abundant northern pike population, fewer of the stocked fish are caught by anglers. So, stocking northern pike often is a waste of time and money. Moreover, a recent Minnesota study has shown that continued stocking of northern pike can hurt other game fish and panfish populations.
Thousands of northern pike a foot long and larger were stocked in Horseshoe Lake in Crow Wing County three times during the 1970s. The northern pike ate perch of all sizes, nearly eliminating spawning-sized fish. Bass and walleye found fewer perch to eat. Bluegill, in turn, seemed to fill the niche once occupied by perch. The result of this chain reaction was the near disappearance of yellow perch, smaller and fewer largemouth bass and walleye, and a proliferation of stunted bluegill. By almost any measure, whether for walleye, bass or panfish, the fishing deteriorated. Only the northern pike population benefited - and it too, declined only after two years after stocking. Other fish populations, meanwhile, required many years to recover to natural levels.
Big northern pike eat large fish and a lot of fish, and so fish managers long thought that an abundance of northern pike would limit panfish numbers, preventing the "stunting" common in many lakes. As in Horseshoe Lake, stocking northern pike to control panfish can backfire. In fact, we have little evidence that an abundance of northern pike (or muskie) can prevent a proliferation of small sunfish. Apparently, sunfish are too prolific and too adept at hiding in thick cover to be controlled by northern pike. There also is evidence that northern pike prefer cylindrical fish such as perch and tullibee rather than the saucer-shaped sunfish.
Everyone likes to catch big northern pike. But why do most lakes carry an abundance of small fish and only the rare body of water hold fair numbers of truly large northern pike? What is needed to grow big northern pike? A lake must have adequate spawning areas to produce a self-sustaining northern pike population. There is little evidence, however, that a superabundance of northern pike fry has any effect on the size to which northern pike ultimately grow. Northern pike must have adequate forage - primarily minnows, perch, suckers, tullibee and other fish of appropriate size. They also must have cool, well-oxygenated water to grow well.
Northern pike are a "cool-water" species, and research indicates that they stop feeding and may even lose weight in the warm water and occasional low-oxygen conditions prevalent in midsummer. So, if a lake is to grow big northern pike, it must have a cool-water refuge, such as deep, well-oxygenated water, with a suitable cool-water forage fish, such as tullibee.
Finally, big northern pike must have protection from anglers. No northern pike ever grew large in a Pyrex baking dish. Large northern pike simply are too few to endure heavy fishing pressure. Big fish must be protected by remoteness, as they are in the Canadian wilds and the remoter waters of northern Minnesota, or by some form of catch-and-release regulations so that most big fish are returned to the water to grow even larger. Restricted harvest is the management approach we must take if we want to grow really large northern pike in the presence of heavy angling pressure.
Recently, anglers and fish managers have begun discussing the use of special regulations to create good fishing for large northern pike. These regulations may take several forms.
A pure no-kill restriction would most closely replicate the conditions that exist on remote lakes that are fabled for their large northern pike.
In some lakes, the DNR has increased the possession limit and imposed size restrictions to encourage anglers to take more small fish. The hope is that through decreased competition, the remaining fish will grow larger. In other lakes, the DNR has banned spearing to protect the large northern pike that otherwise might fall prey to that method of fishing.
Some biologists believe a slot of length limit or maximum-size limit will protect large fish and create a trophy fishery. Meanwhile, anglers could keep some small fish, which are common in most lakes anyway.
What is necessary for Minnesota to steer toward a "big-northern-pike" policy on select waters where northern pike can grow large? Anglers will have to stand up for such a policy. They will have to convince other anglers that catching and re-catching big northern pike is worth more than killing and eating big northern pike.
Interested individuals can read about what DNR fisheries is considering by visiting the Muskellunge & Northern Pike Draft Long-Range Plan page.