Distribution and demography of Southwestern Willow Flycatchers in San Diego County, 2015–19
We surveyed for Southwestern Willow Flycatchers (Empidonax traillii extimus; flycatcher) at 33 locations along multiple drainages in San Diego County, including portions of Agua Hedionda Creek, Cottonwood Creek, Escondido Creek, Los Penasquitos Creek, Otay River, San Diego River, San Dieguito River, San Luis Rey River, Sweetwater River, and Tijuana River. Resident flycatchers were only found on tw