The perch shut off when it's dark. But on the bright side you can troll up some nice walleye in the spots that the perch are in. I'v fished them a bunch this summer at night. (I work until 9 pm
) The eyes hit harnesses on 3 ways . I would end up with 2 to 5 every time out. the best bite is from sunset to 2 hrs into total darkness. Bring a light . I use a little florescent light to light up the tips of the rods . Clean your 3 ways often .
I did one time have perch bite all night long in lake simcoe, Ice fishing??. Don't know why but its rare.