Which iconic desert feature is mentioned as a primary nesting substrate for Elf Owls in the US Southwest?

Answer

Saguaro cacti

The Elf Owl's presence is often dictated by the availability of large cacti, such as Saguaros, or mature trees, which provide essential nesting cavities.

Which iconic desert feature is mentioned as a primary nesting substrate for Elf Owls in the US Southwest?
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