Thank you Bruce, Shorty and Dave W.

Dave I did notice that there were F2s in the study but did not follow the thought out that the F1s reproduced with each other while they could not reproduce with BG or GSF.

Shorty thanks for the info. Like you I would like somone to verify that male BG x female GSF (standard HBG)look much different from male GSF x female BG and does the second of these look like the first pic. on this thread. All the HBG I have seen both pics. and in person look like BG in body shape but have yellow fins and a large GSF mouth much like those posted on different threads earlier this year.

Bruce --clear now. By the way that is a Condello Hawkshead Ground Rat and as BL said it can never revert back to its parent a GSF. :p

Aaron both of those pics. look a lot alike to me. How sure are you of what you have or were sold. If I understand the timing none of these fish have been in the pond long enough to spawn and the two , GG and HBG (BG x GSF) x RES are all that are in there. Give us a history of events of the pond.

Here is a pic. of a GSF for those interested.
http://www.cnr.vt.edu/efish/families/greensun.html

In checking on this topic it appears that there is a large difference (possibly reginoal)in the % of male offspring when a standard HBG is created (m BG x f GSF). Some studies show as high as 97% male others as low as 66% (in a Texas study). If 44% are female and the F1s can spawn with each other, as Dave noted, and you have outbreeding depression (loss of hybrid vigor) as expected -- then someone is going to have an unexpected mess to deal with. ewest

ps: Aaron I see you have posted while I was working on this post-- thanks.