Biology Bluegills begin spawning when water temperatures reach about 70 F. Spawning may peak in May or June, but continues until water temperatures cool in the fall. Because of their long spawning season bluegills have very high reproductive potential, which often results in overpopulation in the face of low predation or low fishing pressure. Nests are created in shallow water, one to two feet in depth. Gravel substrate is preferred. Fifty or more nests may be crowded into a small area, thus creating a spawning bed .
Males guard the nest until the eggs hatch and fry leave.
Young fish feed on plankton, but as they grow the diet shifts to aquatic insects and their larvae. Distribution Bluegills appear to have been native to the eastern half of the U.S. including south eastern Canada and northeastern Mexico, exclusive of the coastal plain north of Virginia. Today, as a result of countless intentional as well as no doubt unintentional introductions bluegill are found throughout the U.S., and northern Mexico. Bluegills are found throughout Texas. Lepomis macrochirus speciosus which is native to the central, southern, and western portions of the state, and Lepomis macrochirus purpurescens a native of Atlantic coast states which has been introduced widely as a sport and forage fish.