Fox investigation

It's mating time for foxes in Central Texas. Finally identified the sound in the night we have been hearing.
Ron said he had heard it for several years while he walked the dogs around the property.
He said he had heard it from inside the house in the wee hours of the morning, too.
We were sitting around the firepit Friday night, as I wanted to see some of the Geminid meteor shower.
The weather was clear in the 40's.
Out of the still, crisp night air came an unidentifiable animal noise.
It was the first time in all the years we lived here that we remarked to each other..."What was that?"
I went down the list of what it wasn't.
First, though it sounded like a howler monkey, I had to eliminate that option since we weren't in the jungle.
It wasn't an owl, though it was more of a screech than anything else. Definitely not a bird, I was confident of that.
A cat? A bobcat? Not a domestic cat. Ringtail cat?
How do you describe it? Howl? Cry? Shriek?
Short vocalization.
A fox?
Just a week previously I had done some "caving" for the first time in years. I was crawling with my belly in mud to retrieve the glow-in-the-dark ball that Opal, my dog, dropped into the known animal den that has been there since I can recall. Over the years, the critter had dug it out more and more with the soft dirt piling up to create a sizable sinkhole under the exposed limestone ledge. I had thought it may be an armadillo burrow, but a friend with more tracking experience than I, thought it could be a fox den. Though I have tracked foxes over moss in the Pine Barrens, NJ, the problem here was that my dogs covered any tracks left behind by the inhabitant.
I had built up a sort of roof of oak and cedar limbs to protect the hole from the dogs digging it out.
This day, though, there was Opal flinging the soft dirt out of the entrance. I told her to stop it before I understood what was going on. I didn't see the ball in there at first.
She is persistent. Finally I gave a closer look and saw the ball, deep in the hole, out of reach.
Recent rains made the ground muddy and clay-like sticky. But Opal was not deterred, so I thought, she can wriggle her way into the opening and get it herself. "Go get it!" I encouraged her and she dove down towards the ball. She knocked the ball further down the hole. Frustrated, she now set to digging at the dirt and sent it flying everywhere... into my face and hair...
She entered the cave but for her white plume of a tail that shot straight up into the air.
I could see her getting stuck and wondering what I would do then.
When she extricated herself, I could see more dirt pushed into the opening than removed. The ball was not in sight. Okay, I thought. I resigned myself to deconstructing the roof of logs so I could get a better look.
Log by log I carefully removed each one and set it aside. I still couldn't reach into the hole that was at the bottom of a 4 ft incline of dirt and then back under chalky limestone bedrock.
Since I hadn't identified what lived there, I wasn't about to blindly stick my hand into the darkness to grope for the ball.
"I am a caver. I can do this." I thought, now resigned to getting dirtier than I was.
There I went, down on my belly, head first, my legs reached out behind me, setting me nearly standing on my head into the opening. At least I could see the ball, though it was still a foot farther under the rock.
In went my head and shoulder and at last I grasped the ball in a successful rescue!
Opal was over-joyed. I was muddy. I rebuilt the roof of logs over the entrance that reminded me of a southwestern pithouse or kiva.
Yes, it must be foxes, I thought as I recollected the fox hole.
Admittedly I had never identified the sounds before.
I have lived here for 25 years.
Friday night, I left the fire to run to my computer to search Google for fox noises.
Sure enough, we found several examples on YouTube.
It was a male calling out establishing his territory.
I then wanted to know more about the gray fox.
I dug out my field guides and still was left in the dark about the wide range of their calls.
I did find out that this is mating season, but not one single guide mentioned their vocalizations which was key for identifying a nocturnal critter you can't see at night.
From what I learned there are playful barks of the young, louder growls when they fight and this yap/scream that establishes territory.
Later that night, towards dawn when I was in the house in bed, I heard the noises again right outside the window.
For now the chickens are safe and I am happy to know that the life cycle of  the gray fox is perpetuated at Dewberry Hill. I am glad they share their territory with us.