Producer survey of bird-livestock interactions in commercial dairies.

The objective of this producer survey was to identify and estimate damage caused by bird-livestock interactions in commercial dairies. The interactions between birds and livestock have previously been implicated in causing economic damage while contributing to the environmental dissemination of microorganisms pathogenic to livestock and humans. Very little research exists to help producers understand what bird species use dairies, why they use dairies, or the scope and nature of damage created as a result of bird-livestock interactions. To better characterize these interactions, we surveyed dairy operators within Pennsylvania, New York, and Wisconsin. Survey results suggest that the most common and destructive bird species found on commercial dairies are invasive to North America, and their use of dairies is associated with the loss of cattle feed, increased operating costs, and an increase in dairies self-reporting Salmonella spp. and Mycobacterium avium ssp. paratuberculosis. Cattle feed loss estimates generated from this survey were used to parameterize an input-output (IO) economic model using data from 10 counties in the state of Pennsylvania (Bedford, Berks, Blair, Bradford, Chester, Cumberland, Franklin, Lancaster, Lebanon, and Somerset). This IO model allowed us to estimate direct, indirect, and induced economic effects of feed loss from bird damage to dairies within these counties. The IO model output suggests that feed loss costs Pennsylvania between $4.11 and $12.08 million (mean $10.6 million) in total economic damage, with approximately 43 to 128 jobs (mean 112) forgone statewide in 2009.