i used to be in sauga for a few years. they are there. the pike in particular. the bass not so much from my experiences. also carp are there.
anyway, you will see people fishing on the east side of the park where the private marina is. they are fishing off that rock jetty that is on the south side of that marina.
but anywhere along the rocks on either side of the park, you will occasionally spot the pike and carp on clear water days with the sun shining above. 2 years ago i saw 8 pike and 6 carp all huddled together in about 10 feet of water. the pike were almost all between 30 to 40 inches. but i only had 20 minutes to fish and i couldn't hook into one.
i know someone that would fish there in the winter too and every once in a while he would land a pike. it was better though when the "three sisters" smoke stacks were there because it was a generating station that warmed the water. but that's been gone for a few years.