There was some discussion in at.banjo on the meaning of "salty dog" towards the end of last year. If my memory serves me correctly, having gone through suggestions such as a dog in heat, it was decided that it was a man having a "relationship" with a woman while her partner was working. It seemed to fit the context of whatever song was mentioned (?Salty Dog Blues - I don't know it - just saw the lines that were quoted) but I can't make sense of it in the context of this song.

Jon