Just got back from a little fishing at Coe Lake in Berea, OH. This is a city park and the lake was created from an old quarrey mine. The local bus route ends its run in the parking lot in front of this lake. About three years ago everyday large groups of people would get off the bus and fish all day long. They started showing up when the crappie first started to move into the warmer water, stayed through the blue gill and bass spawns. At the end of the day they would get back on the bus with hundreds of fish. It only took a couple of weeks to have a huge impact on the fishing.
Today it is just starting to get back to once it once was. You have a few 16+ inch bass or 8-10 inch nothing between. The crappie fishing at this lake was wonderful, 30 fish between 6-12 inches in a couple of hours was the norm. Now if you catch 6 between 6-8 inches it is a great night. The bluegill fishing seems to be recovering faster. You still have decent populations of larger bluegill, however without the bass and crappie to keep the smaller fish in check you now have an abundance of small fish (less than 2 inches).
It is still a wonderful lake. The city has done everything it can so you can enjoy this natural setting. I still take my canoe out whenever I can.