Avian biodiversity in central California vineyards.

Avian biodiversity is declining globally, and conservation lands alone will likely not be able to support vibrant avian communities long-term. However, the integration of wildlife friendly practices into agricultural lands could support many birds that have lost habitat to agricultural and urban development. Here, we assessed how structural, natural, and anthropic vineyard characteristics in Edna Valley, California influence avian species occupancy, taxonomic diversity, and functional diversity from 31 point counts that, collectively, captured large gradients in environmental variation that exist in and around Edna Valley vineyards. Although we found the occupancy of relatively few species to covary with structural, natural, and anthropic vineyard characteristics, increasing canopy cover was associated with higher taxonomic and functional bird diversity in vineyards, and canopy cover and sound level were associated with shifts in bird community composition. We also found some evidence that proximity to surface water and agricultural cover variation surrounding vineyards could increase functional bird diversity; however this requires further investigation. Additionally, vineyard cover was negatively associated with functional evenness, but we did not find evidence that it was related to any other taxonomic or functional diversity metrics. This research could help guide wildlife friendly vineyard management throughout California to help increase the number of birds that can utilize these modified lands for foraging, shelter, and to connect larger areas of protected land.