My best time for perch the last several years on mosquito is thru the ice. Shallow weed beds with minnow and jig worked good. Each year they seem to be getting bigger And more plentyfull as compared to say five years ago. On the ice I'm able to locate the schools easier in the shallower water and also that's usually where the Northerns like to hang out. This time of year on a boat I could never really get a good pattern going. As you said a few here and there, No fishing is a waste of time
I did pretty good fishing the northend from the causeway (in the rocks)this spring while crappie fishing. I kept catching them on my bottom hooks. I don't remember exactly how many I caught, but it was enough for dinner for 2 and I froze a bag of filets also. I think I was just in the right spot at the right time. I think itll be pretty hard to just target perch and do well. but you never know.