Originally posted by Yasik:

Is there any other way to protect the boat?

They are both prevented from spawning by workbench radius, and attracted to workbenches to destroy them. You can use this against them by elevating the workbench and surrounding it with ground spikes and collect the wood and grey eyes. Before I was good enough to build docks I always used the large natural boulders as docking points for portals and such. Once I could build stone I sealed workbenches inside large stone blocks underwater for similar effects with underwater spikes. Keeping the boat in the water a bit away from shore with a big rock between seems to help screw their pathing too as they don't really like moving over the uneven boulder surface, and big rocks are convenient to build portals and chests on for boat collecting ore.

I never had a real problem with events at my main dock except dragons flying in to eat all my boars but I also kept a wood stake fence surrounding my base which went mostly to the shoreline, then dug a deep troll depth ditch around that then grew a treeline around that except for a strip at the beach for ease of access and a set of wood spikes there which was moderately effective and usually destroyed. I'm also a very active defender so I'd just go out and kill everything away from the base anyway. I thought of keeping bees in my treeline for additional defensive fun but bees are rare enough to where I didn't want them screwed with. Wolf pens at the corners might have been fun but I deemed it too much effort for little effective reward. I kind of wish this game had more tower defense aspect sometimes like 7D2D does. My plains outpost is a built up fortress between two stone monoliths and survives constant tar pit slimes (which wreck structure faster than troll, but it's in my backyard as a great resource) and goblin berserkers raids, mainly by being higher up than their AI can deal with so I go out and fight them at leisure.

That is one of the reasons why i build my dock in swamp. Leeches don't attack vessels while there is no people inside. Skeletons and draugr can't swim

I built my house on a peninsula.
You have to walk through it, and use the back door to reach my make shift dock.
Even then I made it a short swim away.

Set a ward near your dock. It will prevent spawning in a larger radius than a workbench but better still is it's alarm feature. Any structure (including boats) that takes damage in the radius of a ward causes a bright flash and sound effect that can be seen/heard from far away.

you can also park in black forest - there are no water-living creatures
or stay close enough to hear crashing sounds

I mean, the boat refunds all of its materials if it does get destroyed, so it's not really a big deal unless some stuff sinks too far (i.e. nails). Then it'll be a pain to get. Honestly, though, I often part my boats in pretty hot spots and don't have an issue with them getting destroyed.

That being said, the Longboat isn't really that hard to build. I'd almost argue it's easier than the Karve to set up since Bronze is annoying as ♥♥♥♥ to mine. Sure, you only need four Bronze ingots instead of ten Iron, but when you think about it, that's eight Copper ingots and four Tin ingots, and Iron is everywhere in the Crypts.

For a smaller critters, you can put a fire next to a boat (boars get scared by it).

You could put some wooden spikes on coast for archers from raid to have a harder time hitting it. (or just make a bait workbenches outside the base as they will target those instead)

Yes, fire works well to keep boars and necks at bay. There is a "lighthouse" (campfire on top of a raised earth pillar and covered with a roof" protecting the karve in a friend's world that we play in, and so far it's done its job.

make a port with palisades as far into the water as possible and put campfires protected from the elements around it or bonfires. Look for good places to build a port, usually the mouth of a river is a good spot. Also make sure to park your boat in water shallow enough that if it gets broken then you can easily recover the mats. Make sure the port is NOT close to your main base where you will be spending a lot of time at least 100~ meters away. At your port you should generally be in and out quickly loading or unloading that way you won't attract spawns and events at your port. Campfires/bonfires will generally keep most critters away from your boats.

If you really want to spend a lot of effort on a port you can make a "safe" port by building walls with palisades in the water just deep enough to let boats travel but not so deep that you can't surround the water area with palisades. It will take a tremendous effort tho and lots and dirt flattening the area underwater to the correct depth.

for me i just build a dock, took me 1 day to finish, and the dock are well protected by a wall, i also create a small river but deep enough to swim so troll cant get near