Diet analysis of wild birds in strawberry farms across the California Central Coast

Birds are increasingly viewed as food-safety hazards and pests in farmlands. Yet birds also benefit growers by consuming pests. Despite limited research into bird-induced crop damage and their inferred role as disease vectors, berry growers are often pressured to prevent birds from accessing their farms. Bird-deterrent practices-- from scaring birds with sound cannons to clearing nearby vegetation perceived as bird habitat-- are common. Our work aims to: (1) identify pest, vector, and beneficial species and quantify their net economic impact on strawberry crops, (2) determine how farms could be co-managed to achieve conservation, food safety, and production goals, and (3) explore how farmers values and attitudes towards birds influence farming practices. Across 30 strawberry farms that vary in farming practices, we will census birds and insects and analyze bird fecal DNA to characterize bird diets and vector status. Our emphasis on birds as pests, vectors, and beneficial organisms will allow us to scrutinize how alternative farming practices affect the benefits and costs that birds impose on strawberry crops. In particular, we will evaluate how diversifying farms-- through planting multiple crops and maintaining non-crop vegetation-- affects the net impact of birds on strawberries. Similarly, we will evaluate the efficacy of existing bird management practices (e.g., sound cannons) in minimizing crop damage and fecal contamination. To develop novel on-farm management practices, we will conduct thorough surveys that determine where pest, vector, and beneficial bird species nest. These analyses will help us identify strategies for preventing nest site access for pest birds and facilitating nesting for beneficial birds. Our project will integrate ecological, sociological, and behavioral research to develop a systems-level understanding of grower-bird interactions.