California raises soil saturation to 90% using artificial seeps at Camp Pendleton to restore endangered Willow Flycatcher habitat, but eight passing birds and no nests are recorded

California’s efforts to restore habitat for the endangered Southwestern Willow Flycatcher at Marine Corps Base Camp Pendleton include artificial seeps and birdsong broadcasts designed to encourage breeding. According to the US Geological Survey report, seep sites had higher soil saturation than nearby reference areas in 2025, although significant improvements were not recorded across all vegetation measures.