Before suggesting what to do, there are some questions.
Is the
boat a junker or not?
Does she have a way of contacting him?
How long has the
boat been there?
I would do a
Documentation and
registration search, then put a lien on it.
If the search shows a mortgage holder, contact them, and say the boat is here and abandoned.
Maybe chain it to the
dock.
I would hesitate to remove anything, or damage the boat. Paybacks could be hell.
As recommended, contact a
salvage company and discuss the problem.