Songbird Indicators for Riparian Restoration Success on the South Fork Kern River

3:20 - 4:20

High quality riparian systems in the West have declined significantly over the recent past coinciding with changed hydrology, lack of tree regeneration, and drought. Riparian restoration has been conducted for recovery of threatened and endangered California songbird species. Typically, early successional riparian willow/cottonwood sites are planted, target songbird species colonize young growth, and sites are checked off on the restoration success list. Restoration and monitoring generally ceases ~10 years after completion of planting. This has been the case in the Kern River Valley (KRV) where 142 ha of new riparian forest was planted from 1986 to 1996 for Yellow-billed Cuckoo (YBCU). The YBCU population rose to 24 pairs in 1992 but now, 30 years after the first willow stick was planted, the species has not been confirmed breeding for 5 years. Speculating historical sites were becoming too mature and dry for YBCU, we enhanced 30 ha of mature riparian forest by adding water and new trees. During historical KRV restoration, Steve Laymon conducted songbird territory mapping in 0 to 11 yo restored sites and naturally regenerated controls and measured vegetation characteristics. To facilitate our understanding of current restoration success, we implemented territory mapping in our current restoration sites and non-restored mature controls. We used Laymon’s historical territory data to determine songbirds associated with YBCU territory use using principal component analysis.