Assessing foodborne pathogen survival in bird feces to co-manage farms for bird conservation, production, and food safety

Because birds can carry foodborne pathogens, widespread concern exists that birds impose food-safety risks to farms. Growers are thus often encouraged to deter birds and forego harvesting crops near bird feces (e.g., no-harvest buffers). Developing a holistic understanding of the pathogen spillover process– from individual infection to pathogen persistence on crops– is essential to understand and manage food-safety risks associated with birds. Here, we coupled field and greenhouse experiments to understand the relative risks associated with different bird species on California farms. We first compared E. coli survival in bird feces on lettuce, soil, and plastic mulch to identify where pathogens are likely to persist. Next, we quantified pathogen survival in feces from 10 bird species to identify higher-risk species. Finally, we combined pathogen survival data with bird surveys and fecal transects to assess food-safety risks across 29 California lettuce farms. E. coli abundance rapidly d..., Our methods include two distinct field operations: first, we collected fresh fecal materials directly from birds in or near Davis, California for our experiments. Second, we collected point count and fecal density data directly on leafy-green farms in the Central Coast of California. The following methods and portions of the results have been included in a grant report for The Center for Produce Safety (Karp & McGarvey, 2024).
2.1 Field experiment:
To quantify E. coli persistence, we implemented a field experiment on the University of California Davis Student Farm – an organic vegetable farm in Davis, California, USA. The experiment focused on two species that are frequently observed on farms but differ in size: Wild Turkey (5,791g; Meleagris gallopavo) and Western Bluebird (26g; Sialis mexicanus) (Tobias et al., 2022). Throughout the spring and summer of 2022, we collected turkey feces by following individuals on the UC Davis campus and picking up samples after defecation with ster..., , # Assessing foodborne pathogen survival in bird feces to co-manage farms for bird conservation, production, and food safety

[https://doi.org/10.5061/dryad.nzs7h450x](https://doi.org/10.5061/dryad.nzs7h450x)

## Description of the data and file structure

All data for associated publication are included. Specific data include (1) experimental data (experiment_field.csv) from the field experiment; (2) experimental data (experimentlab.csv) from the laboratory/greenhouse experiment; (3) raw point count (pointcount.csv) data, including birds observed and associated information; (4) bird occurrence found from sequencing analysis (fecal_sequencing.csv); and (5) fecal mass (fecal_mass.csv) and associated bird mass data.

Descriptions of the procedures involved are included in the methods description and the resulting manuscript.

### Files and variables

#### File: Spence\_Dryad\_Submission.zip

**Description:** All data are stored in CVS files. Each file has an associated README csv, that pro...