There are "salvage" rights, but, a person needs to really study up on this stuff.
For myself, it not worth my time, unless a person were to ask for help. And then, we are not sure we would be compensated for our efforts.
"Pure Salvage" is the term I think you need to read up on.
BoatUS Towing Services: Towing vs Salvage
The reference is only that, and for a starting point to "learn"!