I haven't got a clue as to what it could be. When I was in college,back in the late 60s, a friend and I would rent a skiff and 10hp outboard from the marina that was next to the Edmonds ferry dock. He would launch us out on a long rickety rail track. It took forever to get to possession point to do our fishing, but was always worth the trip. Ive seen a lot of stuff out in PS and Admiralty inlet. On one of our trips to possession I was looking in the water and saw a large whale shark or it may have been a basking shark pass under our boat. Whichever one has the light round spots on its back. So they.re out there. Dan out