It's a rainbow. The spots on the tail confirm that it's not a brown. (browns can be silvery too!) It's not a salmon. Salmon, landlocked or otherwise have a distinct head shape, (more refined, pointy nose) and even though the head shape is not used as an id reference, I have drawn enough trout and salmon to know the difference. Further, Kokanee have barely visible spots and usually only on the upper caudal fin. Landlocked coho have spots on only the upper caudal as well. King salmon (landlocked or otherwise) have spots on both upper and lower caudal but your's is clearly not a king salmon since there aren't likely to be any in contiguous water. BTW, a good mnemonic for identification of King Salmon vs. Coho for ocean fishermen is "King of Spots" for king salmon as they have the most spots on their tail, both upper and lower.....