Give or take a few weeks, when and where it occurs is common knowledge. I happen to know a fair amount about Great Lakes game fish, but even if I didn't, I could read up on them, look at a map and tell you when different species enter which rivers to spawn. I'd simply find out their preferred spawning temperatures and cross reference that with the spring timing it occurs in that geographical region. The next two locational factors are available structure and cover. I pair them together in this discussion, because fish use them for so many similar reasons.
Structure is simply the shape or bottom make-up of lakes, rivers and reservoirs.
Structure types are differentiated by their shapes and bottom content. Now their shapes also play a role in attracting game fish. Knowing the best feeding opportunities fish have available, lets us follow the dinner bell directly to their location. All game fish are predestined to feeding efficiently. Energy is not to be wasted.