During the spring of 2015, I documented a pair of California Gnatcatchers (Polioptila californica californica) nesting in the foothills of the San Gabriel Mountains of Los Angeles County, in Grasshopper Canyon north of the town of Castaic and west of Castaic Lake. I located one pair with three dependent juveniles and three nests: one nest from a previous year, one recently active nest, and one nest built and
occupied during the observation period. I found these gnatcatchers 13.8 km north of the northernmost pair of the California Gnatcatcher previously reported to the United States Fish and Wildlife Service (USFWS; data available by request to the offies in Ventura or Carlsbad, California).