These are an unexpected find. It is an unexpected location for many reasons that I cannot go into detail about.
The weather has been absolutely horrid. Very cloudy most of the time it seems, so it makes for very dark conditions amongst a group of trees. The photo at the bottom I actually got caught in a passing rain storm.
I actually heard the sounds days before I saw them at the tree hole. The first few days they did not appear at the tree hole. I walked on all sides of this tree and the sound appeared to come from the other side of the tree no matter what side of the tree I was on. I concluded it had to be inside the tree. I even had a friend listen to a video of the sound to confirm it was an owlet. I never heard them make these sounds inside the tree hole, only after they ventured out of the hole. Then I saw one on a different day appear at the hole. On another day I saw two heads. It almost appeared the one would push the other out.
All of these photos, but especially the one on the bottom are taken in very low light conditions at a high ISO. Even in a location you would never think an owl would nest, they might. Enjoy the rest of your week!