That's basically what Boone and Crockett is saying about it.
This is a quote from their website on this ram:
"Bradley Visser's 2010 sheep hunt didn't get past opening day resulting in this fine Idaho bighorn ram estimated to green score 189.
The ram was reported to be a California bighorn. B&C records do not recognize California bighorns as a separate category. Genetically, the two can be separated, but due to sheep reintroductions and cross breeding it is rare to find a pure strain California bighorn. California bighorns have a genetic tendency toward small horn growth. A ram scoring as high as 189 is most likely a bighorn.
The state record for Idaho is a ram scoring 197-7/8. The state record for Washington, another state with both bighorn and California bighorns, is 196-28. Both of these rams are bighorns."