I've killed gobs of those fat black bastards where I live, we've got them in NW Washington, too. A mix of blacks and greys, sometimes more greys than blacks, sometimes more blacks than greys. I've never seen a white one though.
The black ones around here often seem to be more aggressive, and less skittish from humans. They are also creepier. One time one of those bastards sat up in a tree in my backyard, about fifteen feet up in it, staring down at me/watching me while I was working on my computer, looking out the back window with the screen door open. Was working on my latest novel. I was waiting for the next customer on my bird feeder, which is set up low on the ground on a tree, with heavy backstops behind it, (including one which is about a 6 or 7 inch thick piece of lumber.) covering the neighbor's fence.
I couldn't blast the vermin out of the tree, because of the neighbors house facing behind it, and the angle of the shot could also possibly richochet slightly towards another neighbor off to the right a bit. I can only shoot them if they're on the ground, or on my feeder. I'm extra cautious and take no chances with a missed shot or flier going off into anywhere but my yard or trees/tree trunks.
Bushy tailed rat knew this, it seemed, and just sat there on his branch, barking and screeching down at me for like half an hour! Pissed me off! lol.