I fished Port Alberni this summer on a friends boat. The second morning we got to the boat that was moored at the China Creek Marina before light. Our plan to get an early start were dashed when we noticed that both electric Scotty downriggers were missing. They were held down with the Scotty locks and a cable. The boat next to ours was missing his downriggers also. A quick look around reveiled that a bunch of boats were missing downriggers and the day before the big salmon derby there. The manual downriggers were passed over. Seventeen downriggers in all were taken and about 25 % had the Scotty locks. The surprising ending to this story is that all the downriggers were recovered that morning. A boat (stolen also) was reported drifting out in the inlet with no one on it but a bunch of downriggers sticking up from the stern and a few on the bow. It turned out that the person stealing the boat and downriggers was using the kicker motor and the bow line drift back and got caught in the prop. He abandoned the whole operation and left it drifting. I have not heard if anyone had been arrested for the attempted theft. After reterminating the electrical wires which were cut we finally got out fishing by noon. Within 10 minutes of fishing we had a pair of 20 pound kings on the line. The day ended surprisingly well after the initial grim prospects.
The bottom line, the Scotty locks are only going to slow someone down, not necessarily prevent your gear from being stolen.

Deepwater