U.S. Department of Agriculture: Animal and Plant Health Inspection Service





Date of this Version



Elser JL, Adams Progar AL, Steensma KMM, Caskin TP, Kerr SR, Shwiff SA (2019) Economic and livestock health impacts of birds on dairies: Evidence from a survey of Washington dairy operators. PLoS ONE 14(9): e0222398. https://doi.org/10.1371/journal.pone.0222398


The survey described in this research paper aimed to investigate the economic and health impacts of birds on dairies. Birds are common pests on dairies, consuming and contaminating feed intended for cattle. As a result, dairy operators experience increased feed costs and increased pathogen and disease risk. We surveyed dairy operators attending the 2017 Washington Dairy Conference to examine the impact of birds on dairies in Washington State. Dairy operators reported feed losses valued at $55 per cow resulting in annual losses totaling $5.5 million in the Western region of the state and $9.2 million in the Eastern region of the state. Shooting was the most commonly used bird management method and European starlings (Sternus vulgaris) were the most frequently implicated species statewide. Bird abundance greater than 10,000 birds per day was associated with larger herd size and with self-reported presence of Johne’s disease and Salmonella.