Hey Rowly, sounds to me like fish from previousy established populations. Most spring spawn bass I have seen this year (SMB at least) are only now in the 2" range... 5+" seems extremely large to me for fish that would be less then 6 months old... even IF the introduced adult bass did spawn at all this year for you. Had you noticed any fingerlings/fry before this? Bare in mind it normally takes 4+ years for a bass around here, (Ontario), to reach 12" long.
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