Animals
In a year 2000 study conducted by the Lake County Lakes Management Unit the following wildlife species were observed on Countryside Lake:
Beaver Castor canadensis
Woodchuck Marmota monax
Reptiles
Painted Turtle Chrysemys picta
Snapping Turtle Chelydra serpentina
Many deer. Here is a July 2016 photoshoot (7/10/2016), on the north side of the lake.