Strangely we already have what seems to be Bluegill despite not stocking it.
Okay -- you currently have greensunfish (GSF) in your new pond. They likely arrived at some point from water in the ravine or dry creek GSF are notorious as early unwanted invaders of new ponds that have any remote connection to a ditch or even a dry creek bed. High water events and heavy rains are very good for distributing green sunfish. Texas has GSF as common as mosquitos.
GSF are 1/2 of a hybrid bluegill (BG X GSF = HBG). Thus adding HBG to your pond is a logical step. HBG with adequate food can grow to 8"-12" long. LMB bass even as 10"-14" fish in your pond would control sunfish reproduction, minimize sunfish stunting and provide excitement for young anglers.
My main concern is same as several others that the tree lined shoreline will eventually cause significant water quality problems in this long narrow pond. A large amount of tree litter will find its way into the pond. These organics will consume huge amounts of dissolved oxygen that at certain times will cause fish kills in some areas of the long narrow pond even with solar aeration present. As this happens, bass will die first and GSF last. GSF can somehow manage to survive when the pond has 0 oxygen. Thus as bass disappear due to fish kills, you will periodically need to restock some of them to maintain some sort of fishery balance.
