In a small pond that has several generations of established HBG, if a few adult female CNBG or regular BG are stocked will they back cross with the male hybrids and make 3/4 BG off spring? and of coarse a mixed pond of Hybrids just with a higher % of BG genes?
They are certainly capable of doing just that.
You say you already have several generations of HBG established? That's not normally considered the ideal scenario, although there are reports of F2's and even F3's that are achieving good sizes in their own rights.
I'm dying to know... what do the HBG offspring that were hatched in your pond look like? GSF? Stunted? A high percentage of defects? Perfectly normal? What sizes are you seeing, and how do they stack up against the F1's?
Welcome Bobby.
There are published peer reviewed studies on both sides of the question "can HBG backcross with either parental species". While I think they can but with very limited success in #s surviving to viability , that is not an absolute proven scientific result.
Outbreeding depression in HBG FX generations doen not mean a backcross with a BG will be 1/4 GSF and 3/4 BG. Genes don't necessarily line up like that. The alleles may combine to give near 100% of a certain BG trait while also having near 100% of a different GSF trait. There are lots of unanswered questions on the genetics of fish especially common sportfish like BG and GSF.
As far as what the off spring look like, well they look kinda like the parents. some leaning towards the BG pheno type and some more GSF. Hard to tell if they are stunted. Definitely some are smaller but not sure if they are just younger. The fish looked thin for some time as the only two things in the pond are those and Gambusia. I am assuming that the HBG are not the best fish eaters as The gambusia are wall to wall. We Started to feed pellets to add some wieght to the HBG. Koi have been added as an ornamental also and after several spawns no baby koi have made it as the gambusia ravage the hatch-lings or just eat the eggs. I recently added a few 6-8 inch snook and tarpon (3 each) to work on the Gambusia. I added on red drum about 12 inches or so to eat the baby Bream. I am also under the impression that the HBG are mostly male so If I added a few adult female BG they would increase rate of production to help feed the few predators I have added. I also plan on adding a few more. A coupe Mango snapper and a southern founder or two. the pond is maybe just under half an acre.