The most bizarre thing just happened in my fort...
First a little backstory... I tapped the cave river many years ago, and set up cage traps to prevent the wildlife from venturing into my fortress. As such, I have about 14 tame cave crocodiles roaming the halls. They are great for defense and have snatched their share of kobold thieves over the years.
Several years ago, I found the corpse of the Human Guild Representative in the main stairwell, with a few human chunks scattered around as well. I never caught the culprit, but I suspected one of the crocodiles went rogue for one reason or another. If it did, it never attacked anything else, and I forgot about the issue, besides the annoyance of not being able to place special orders with the humans.
Just now, however, a crocodile named Mulodlug has embarked on what I can only describe as a campaign of serial vandalism in my fortress. He only targets statues, and I have quite a few statues sprinkled in the common areas of my fortress. My log is filled with "Obsidian Statue toppled by Mudolug, Stray Cave Crocodile (Tame)". But none of my fortress guard, military, or other animals seem to care, even though he is listed as "Hostile" in the unit list and is doing this all in broad, um, fortresslight.
Anyone have any idea what's going on here? I'm not discounting the possibility that he killed a dog or something before I tamed him, but he never attacks any of my dwarves, and I verified in a recent save that he was named, yet listed as Tame in the unit list instead of Hostile, before this iconoclasm began. I'm not considering it a bug because it's so hilarious, but i can't think of any documented behavior that would cause it.