Yellow-rumped Warblers are filling the backyards, parks, and campuses of Southern California. These sweet, slightly hyperactive birds are a welcome sight for residents of Orange County and Los Angeles. On one single day at the UCLA Williams Andrews Clark Library, a birder scoped 50 different "butter butts."  Another birder saw 125 in one hiking trip in Franklin Canyon Park! Audubon California's Starr Ranch Sanctuary are also having a mellow yellow kind of month. Seeing large flocks this time of year is not unusual, the species land here every fall, but it is still something to behold. The bird above and below (male and female respectively) illustrate what to look for — the duller color these birds wear during this non-breeding season.

Look for these large (for warblers) energetic birds foraging in shrubs and catching insects in air. It is not uncommon for them to bully larger birds like Black Phoebes for the best habitat set-up.

While their spring color may be more celebrated by bird photographers, there is something to be said for the subtle beauty they exhibit in fall.

Photographs by Kelly Colgan Azar.