Crappie spawn first each spring, before other fish.
Green sunfish spawn shortly before bluegill, and each species often use the same nests.
Green sunfish spawn once yearly, bluegill spawn several times.
Sheer numbers of bluegill, over time, can race past green sunfish numbers. But, greens have a larger mouth, so can fight their way through to survive.
If there's another predator, such as bass, green sunfish numbers decline over time, compared to bluegill.
I found a lake in the Texas Hill Country, back in 1988 that was overpopulated with green sunfish. Our electrofishing survey showed no other species.
This five acre reservoir sat directly below a defunct turkey farm.
Water was rich and green.
We stocked advanced bass, 12-14" long, and 400 adult bluegill.
The next year, bass ranged from 6-17" (they spawned), green sunfish numbers were down, and bluegill numbers were low.
Year two, bass ranged from 6-19", green sunfish numbers were low, bluegill numbers were up, and we recommended a slot limit on bass.
The third year, green sunfish were rare, bluegill numbers were high, bass looked like footballs.
