[1.0.1941] Silent visitors?

[erdrik]

I was watching my colonists harvest some trees when I saw a visitor and thought "oh look, someone from The Baircampe of the Basin". Then I thought, "wait .. when did that guy show up?"

I checked the messages history, and there is nothing logged for his arrival.
I didn't see anything listed in the 1.0 update thread that mentioned sneaky or silent visitors, so Im posting here under the assumption it is a bug.

(Though, to be honest I wouldn't be at all off put if it was a feature. It would be kinda cool if enemies could also silently show up for spying or other non-violent but still hostile reasons...)