Sunfish are spring spawners, with spawning for some species extending into early summer. Males build nests which are saucer-shaped depressions in the lake or stream bottom. Males also guard the eggs and newly hatched young. A few days after they hatch, the young rise out of the nest, at which time the guarding parent leaves them to care for themselves. All sunfish are carnivorous.
Larger individuals feed heavily on fish and crayfish.