Originally posted by blprice61:

I believe torches may also help in deterring anything with a fear of fire so that might help a bit with port security against lesser troublemakers.

It is a year ago so it may have been changed, but..
In my first ever world I had a bonfire left and right of my dock entrance. It was still a greyling shooting arena and bad place to keep my boat for extended periods.
The mouth was in line of sight from a patch of forest though.

Another harbor project had the entire town hidden behind landscaped walls that were way higher than anything, and the wall ran into the sea for a bit. The dock was completely closed in with walls and roofs except for the entrance. Again, fire at the entrance.
They still swam in.

I did have some success with a karve sized boathouse once. Besides surrounding walls and roof it had 4 gates blocking the entrace, bottom set blocking swimmers and top set blocking view.
It was a bit of a hassle to open and close them each time, but in its surroundings it was a fitting build; quite pretty at the time of day when the light grows a bit more diffuse, sitting on the side of a hill next to a forest lake.
This sort of setup won't work for longship though, because those are too wide for gates.

Tbh I'll be really happy if you tell me that I missed a major change.
I haven't paid much attention to patch notes between my active periods.