Lake Sapanca in hosts a diverse array of fish species. Among them are the European Eel, Big-scale Sand Smelt, and Black Sea Shad. The lake is also home to the Angora Loach (Cobitis vardarensis) and various members of the Cyprinidae, including Common Bream, Italian Bleak, and Common Bleak. Northern pike, goby species like Caucasian Dwarf Goby, Racer Goby, Round Goby, Monkey Goby, Syrman Goby, and Marine Tubenose Goby add to the richness. Additionally, the lake supports Pumpkinseed, European Perch, European River Lamprey, and Salmonidae such as Rainbow Trout, Black Sea Salmon, and Salmo Cettii. The Siluridae family is represented by the Wels Catfish, while Syngnathidae species include Black-striped Pipefish and Narrow-snouted Pipefish. This biodiversity extends to birds, mammals, amphibians, reptiles, insects, and various plant species in the lake’s vicinity.