Type: report

Article abstract: Consistent with our proposal dated March 25, 2008, the Irvine Ranch Conservancy and consulting biologist Robert Hamilton have built, installed, and monitored several experimental artificial nesting substrates for the Cactus Wren (Campylorhynchus brunneicapillus; CACW) in the Irvine Ranch Wildlands in central and coastal Orange County, California, within the larger Nature Reserve of Orange County. The wren is one of two avian ―focal species‖ of the Natural Communities Conservation Plan (NCCP) for coastal sage scrub in southern California, and its populations in both the central and coastal NCCP reserves are of special conservation concern due to rapidly declining numbers, reduced availability of favorable habitat with adequate nesting sites related to the wildfires of the past 16 years, and increasingly isolated sub-populations.