Initially, eggs are laid individually every 1 to 2 days. During the incubation process, female owls rarely leave the nest except to defecate and get water. To help with incubation, female owls have a sparsely feathered brood patch on their bellies that has a higher percentage of blood vessels than other parts of the skin. Blood flow through these vessels creates a good source of heat (in the range 101-103)for the eggs.
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