We saw these owls a couple of years ago. Owls may lay up to 14 eggs during years of rodent abundance, but fail to breed when rodent populations crash. Eggs are laid at intervals and incubation begins with the first egg, thus the hatchlings differ in size and the number raised to fledging depends on the food supply. Owls are smart. Like so many animals that are not given the credit they deserve. 

Usually only the female incubates and the male brings food to her; both sexes feed the young. Incubation is relatively long, being 32-34 days in the Barn Owl. Owls reach maturity at one year.

Gray Hawks are not found anywhere in North America other than Arizona or southern Texas

These are magnificent birds and we were privileged to see them flying free  in the Sonoran Desert Museum in Tucson.