Ruby-crowned kinglets forage actively in trees or shrubs, mainly eating small insects and spiders, some berries and tree sap. They may hover over a branch while feeding and sometimes fly out to catch insects in flight. The red crest is raised when agitated or in display. Often, they perform a “broken-wing” act to draw predators away from their nest, which they will defend fearlessly, mobbing the intruder which may be a cat, squirrel, or human.
The Yellow-rumped Warbler breeds from eastern North America west to the Pacific, and southward from there into Western Mexico. “Goldman’s” yellow-rumped warbler is a non-migratory endemic within the highlands of Guatemala and the black-fronted warbler is also a non-migratory Mexican endemic. The myrtle and Audubon’s forms are migratory, traveling to the southern U.S., Mexico, Central America, and the Caribbean for winters.