Walleye/Perch forage base?

[moreyes]

Just looking for some thoughts on a lake that I fish in northern MN. The lake is about 500 acres and 36' at the deepest point, lots of structure, kind of a resivoir in a way with a dam at the outlet about a 3' foot high dam. In talking with the DNR about the lake the main forage base in the lake is Perch with a few creek chubs thrown in. Would you find Perch schooled up and suspended in deeper water, I have trolled across certatin areas and have had dark patches appear on my locater, do you supose those are perch? Where would you you concentrate your efforts weeds shoreline or suspended schools? It is great little lake no public access, classic walleye structure, lots of rock and gravel and no pressure opener 10 boats tops.

Think spring,good luck moreyes