I've been getting lots of natural hybrids from this sediment pond because of a few GSF that got in there somehow. That is ok with me as I like the HBG. Here is a picture of one that has grown to decent size.
The markings on this hybrid are very similar to a lot of smaller size fish I have moved from this sediment pond to my main pond. I'm guessing it is HBG but RES/GSF would also be another possibility as there were actually more RES (175)stocked in this pond than CNBG (100).
Edit: Now that I look at the fish in the picture again, could it possibly be a CNBG/RES hybrid? Awfully small mouth for a HBG that is traditional BGxGSF parentage. White tipping on the fins like my CNBG.