Although it has a larger mouth and more elongated body than the bluegill, the green sunfish has the blue tab on the gill cover and is often confused with the bluegill. Commonly referred to as perch, green sunfish are aggressive and easy to catch. However, they can easily overpopulate and become stunted in small waters. The Kansas record weighed 2 pounds, 6 ounces. The world record greenie is listed at 2 pounds, 7 ounces.