perch walleye photoScientists already claim that climate change is already hurting yellow perch reproduction in Lake Erie. Scientists have been measuring the temperature of Lake Erie waters and the Lake is getting warmer each year, along with the lake winters getting shorter. So if it's hurting the cool water fish species such as yellow perch, you know it's going to affect the walleye as well. DNR have been measuring how walleye and yellow perch hatches were below average last year, it's not good.