Many species of fish and other aquatic animals populate the lake. The most famous fish to catch in Lake Tinaroo is the world record Barramundi. The barramundi can grow to an enormous size in the lake because they have no natural predators. Each year, the lake is stocked with young barramundi from the Walkamin Research Station as the species is unable to breed in the lake due to the lack of access to salt water. Also present in Lake Tinaroo are sooty grunter, sleepy cod, mouth almighty, archer fish, spangled perch, long tom and many species of crayfish, including the red-claw and yabby. A Stocked Impoundment Permit is required to fish in the dam.