After seeing someone else's photo showing 6 distinct screech owl fledglings perched on the same branch but more seperate from one another, I took a closer look at photos taken the same day. I believe there are 6 in the photo. No. 5 and No. 6 are two different shapes.

When the photo was taken, an adult screech owl was still perched near the nest (someone saw a baby screech still in the nest). So, quite possibly there are 7 fledglings.

The female screech owl lays up to 8 eggs in the nest. For 5 to 7 eggs to hatch and survive to fledgling is quite the accomplishment. You would need to have an abundant food source. The winter was not as cold and there was also less snow on the ground making it easier to find food.