Teh waterdogs are like a med. brown /black with a lighter brown streaks.
Oh wait I have a pic of one but it has a hook through its head let me get it.
if you look at the back part of the tail on the left side thats what color they are most of the time, this one is a early spring one and is green.
also the browner ones have the strips that you did.
when I first saw the pic of yours my imediaty thought was hey that looks like a waterdog, including the shape.
Disclaimer: the waterdog in this picture was a stunt double, he was not hurt or harmed in anyway shape or form due to his training, this is what waterstunt dogs do for living. He was swimming beautifully after 5 3lb bass at a local pond. he did look a little tired however when we last saw him he was in the mouth of a 6+lber fighting furiously to get out.