Good question and something there's lot to think about. My way to deal with this is this: When I do a finished drawing, I always sign it in the end with my name or just initials, and the year. As I mostly drew on actual paper I write the signature physically too, so it's always a part of the work. The point of this is that the work would always be linked to me, even slightly, but the signature is not showy so it doesn't affect the use. This kind of version is what I deliver to the client for example to be printed in a book. I trust the client that they will respect my copyright, add my name somewhere printed too, but still fully use the publication right that I have sold them.

However, when I upload the map to here, to my website, or somewhere else on the internet, I use a different version of the map. Before showcasing I digitally add my full name, year, ©-symbol, and my website on top of the map in addition to the original small signing with initials. The reason is that anything that is uploaded to internet may start wandering around and end up in surprising places and possibly unlicensed uses. To make this a bit more unlikely, I make sure my name is there and my website, if someone sees it out of context.

At least in Finnish laws copyright comes always automatically to the maker without any signing, but in the web I'm a bit wary. In short, the maps I upload here are not the same versions I send to my clients.