Cecil and CJ: I don't have much personal experience with muskies, and I'm not sure we have a good knowledge base in the profession on spawning and reproduction. I don't know why so many of the stocked populations don't spawn -- they prefer spawning on submerged vegetation, and that usually is present.
As for the NOP usually out-compete Muskies theory, we probably should call it "often" rather than "always." As CJ said, the northern pike spawn early, in the 30s, just after ice-out, while the muskies don't spawn until later. Optimum spawning temps are in the mid-50s. So, the thought is that the little northern pike are already spawned and just waiting to eat the small muskies. NOP seem programmed for built-in cannibalism anyway, and I'm sure a small musky looks pretty darn familiar to them. I do know that the MN and WI biologists who manage lakes with natural musky populations get very upset if northern pike get into their lake. It is not always the kiss of death, depending on habitat perhaps, but it often can result in a loss of the musky natural recruitment.
