LANDSCAPE AND VEGETATION FEATURES IMPROVE RESTORATION SUCCESS FOR BIRDS: USING THE RIPARIAN BIRD INDEX TO EVALUATE CREEK RESTORATION IN CALIFORNIA RANGELANDS.
Kathleen E. Grady; Sonoma State University; 1801 E Cotati Blvd, Rohnert Park, CA, 94928; (415) 728-8193; kgrady121@gmail.com; Derek J. Girman, Tom A. Gardali
In Marin and Sonoma Counties in California, riparian restoration aims to counter the negative effects - a decline in riparian habitat and its associated benefits - that grazing has often had. We examined avian response to riparian restoration on grazed lands to measure restoration success. We conducted avian surveys on 40 plots within 20 sites in seven years between 2001 and 2016. Sites ranged from 0 to 27 years since revegetation. All surveys were scored using the Riparian Bird Index (RBI), a richness index that gives higher scores for species more closely associated with riparian vegetation. RBI scores were found to increase with increasing restoration age. Vegetation data were collected in 2016 to examine the effect of local vegetation on RBI score. Canopy cover and non-willow tree canopy were found to be significant predictors of RBI score. At the landscape scale, the highest-ranked model suggests that corridor width and the size and proximity of the nearest protected area were significant for RBI score. Our study shows that riparian restoration within this study area has been successful for birds. We suggest restoration planners target sites close to large protected areas, plant diverse native tree species to increase canopy cover, and maximize the width of restored areas.
Ecology and Conservation of Birds I