What kind of fish is this?

I live in southern ontario, canada. Around the north part of lake simcoe in orillia. My house is on the lake and the other night (midnight) I went to the beach. When I got there I heard a splash and quickly looked with my flashlight. I first saw a fish that was around 2 1/2 ft long and then I saw thousands of little things that looked like black minos. I couldn't tell if the fish was a catfish (couldn't see any of the whiskers) or a pike. It had a long wavy fin on its top from mid section to very end. It had a long slender body and flat face, thought I saw teeth. What kind of fish is this? Also, what were he black minos that it was guarding? Were they babies?