There wolf.
Ring Wraiths?
Knowing there were two of them makes me lean towards 'coons. IME, they often move around / forage with a cohort or two. I’ve live-trapped coons quite a bit (to move 'em fat away from my veggie-garden) and more often than not, there would be a pair of coons in trap - not just one. Like the second coon to enter trap HAD to have had its nnose up the first one’s butt as trap was not meant for large/long animals.
And coons can make some odd and varying sounds when they are ‘talking’ amongst themselves, or so I have heard. 
House elves, obviously.
Trump? Or has that gotten old already?
Why are you talking that way?
Sometimes trapping local critters can present some interesting situations.
Such as: Two for one
:rolleyes: 
I am leaning towards it being raccoons, since it seems they make many interesting sounds, although I haven’t yet found a recording that precisely matches what I heard. I probably erred in describing the sound as a growl, because it was more continuous than a growl, more like a purr.
For those who expressed concern, sightings of black bears are very, very rare in these parts, to the point of being mythical. I’ve known only one individual who even suspected the presence of one (by scent; she had formerly lived in Alaska and was familiar with the smell) and that was over 20 years ago and out in the boondocks. I double checked today with my most outdoor-expert friend, who actually lives near a conservation area, and after she stopped laughing she assured me that no, there are no bears here.
I did remember to bring a flashlight with me (and by the way, when I flung open the door and yelled, I was still in the building behind a screen door). What’s really annoying is I own a night vision monocular which I also did not have with me, plus we have a trail cam, but it wasn’t set up because it has decided to take 3000 pictures in the daylight and none at night.
Anyway, probably raccoons.
Or werewolves.
So where is Rod Serling when he’s needed now?
Skulking about behind the building grumbling to himself.
Raccoon. I had the great misfortune to have an entire family living right around my yard–they’d seldom come into my yard because of the dogs, but they were all over the neighbor’s yard and up the huge ancient fir tree between our houses. One night the lot of them were up the tree and were either fighting or fucking (possibly both!) and making the most outlandish noises. Growls, snorts and squeals like pissed off pigs and general ruckus as they squabbled about. I have never before nor since heard raccoons make noises like that and I had no idea they could sound like battling pigs up a tree. I shone a maglight up there and saw the lot of them clinging to the branches and even though they stopped when I went out there, they went right back to it once I went back inside. Eventually I went out with the hose and ran into my neighbor from across the street–luckily, the hose broke up the snort party because my neighbor had his .45 pistol and was all ready to shut that shit down right quick.
So yeah, raccoons, I’d bet on it. They hiss, too.
And they have a lot of teeth.
Scary clown?
Frumious Bandersnatch?
Vermicious Knid?
Perhaps an intoxicated person searching for his vorpal sword.
My threads usually aren’t this successful. I’m rather thrilled with the responses. Thank you all.
And, you ain’t dead. There is that, too!
Don’t assume anything on All Hallows’ Eve.
porcupines do make snuffling noises. And I’ve seen several dead ones this month, so they’re definitely out and about.
I know, I know, you don’ need no stinkin’ badgers.