Mrs. Owl is in the box again this morning after nearly 12 hours out of the box last night. She was gone from 7:52pm to 7:14am. The first photo shows her returning through the entrance hole. Thus, we didn't observe any feedings at all last night.
Yesterday was quite a hot day (87 degrees), and Mrs. Owl spent the afternoon off the egg, mostly with her wings spread for coolness. She also panted, using a motion called "gular flapping" in which her throat pulses with her mouth open to help cool her down. She spent some time in the entrance hole, looking out into the sun.
We haven't noticed the ants at all in the last day. My guess is that they probably were attracted to any mucus or smell that may have been on the egg when it was freshly laid. Now that it is just a dry egg, they have no more interest, and have gone back to whatever they were doing before the egg was laid. In any event, Mrs. Owl seemed to pay no attention to them when they were there, and doesn't in any way seem irritated.
This morning, she seems like she is settled on the egg, so perhaps she is either beginning ot incubate it, or is perhaps pondering her second egg, which is due today. Typical clutch sizes are 3-4 eggs, but they can number as few as 2, or as many as 6. More experienced owls tend to have larger clutches, probably because they are capable of finding more food.