Based on this underwater photo I took in the Straits some years ago, I'm saying Coho. Spots on the head, but more wormy lines on the back.

I caught a salmon in Wrangell last year that looked like it could be a cross between a Sockeye or Chum, but with spots on its back and thought it was a Silver until I looked at the photos. I'm still guessing on that fish and will post an image later.

Here's the Coho shot I did in the Straits.