Coho or Chinook in Anderson Ranch?

A friend recently told me that during the summer he caught a Chinook salmon at Anderson Ranch Reservoir while fishing for Kokanee. I told him it was most likely a Coho and not Chinook, but he insists it was Chinook. Today he sent me a photo of that fish, and as one might imagine, I cannot see the gum line at all (the fish's mouth is closed), and it is not a clear enough photo to detect spots on the upper or lower lobes of the tail. So with no other evidence available, my question is: are there Chinook in Anderson Ranch? BTW, it is most certainly not a Kokanee and therefore must be a Coho or Chinook.
I hope you didn't have a wager with your friend.  Fall Chinook Salmon have been stocked numerous times over the years in Anderson Ranch Reservoir as a management tool to control/reduce Kokanee Salmon numbers so they grow at an optimum size to provide a quality fishery.  Fall Chinook forage in the same level in the water column as Kokanee and are very efficient at eating Kokanee.  They also provide an exciting fishery because of the size they reach at 4 and 5 years of age.  We had a picture sent us recently of a Fall Chinook Salmon from Anderson Ranch Reservoir that was in excess of 30" and 15 pounds.
Answered on: 
Tuesday, August 25, 2015 - 11:46 AM MDT