This bird, a very rare species in California, delighted birders in the unlikely habitat of the San Francisco financial district in the winter of 2008. Birds of North America Online describes the foraging behavior pictured here: "The Worm-eating Warbler is perhaps best known for its habit of hopping through the understory and probing into suspended dead leaves for food—its primary foraging technique on the wintering grounds ... Worm-eating Warblers eat mostly caterpillars (once known as “worms”—hence this warbler’s name), other insects, and spiders."