Weighing the benefits, risks of wild birds on organic farms

Western bluebird with cricket. Photo by flickr user Kevin Cole.
Western bluebird with cricket. Photo by flickr user Kevin Cole.

PULLMAN, Wash. – Washington State University researchers will help organic growers protect human health by assessing the risks and benefits of wild birds on organic farms. Researchers received nearly $2 million from the U.S. Department of Agriculture Organic Research and Extension Initiative to conduct the study.

“For fresh produce growers, food safety concerns about E. coli and salmonella have become a big issue that’s causing somewhat of a generalized freak out,” said Bill Snyder, the WSU professor of entomology leading the study. “We’re trying to figure out where these pathogens are really coming from and how to manage them.”

Many organic growers create habitat on their farms to feed and shelter birds because they are important predators of insects that can damage crops. At the same time, wild birds have been implicated in the spread of harmful pathogens like E. coli and salmonella.

Snyder said there’s not a lot of rigorous research that looks at these connections across diverse farming systems and different bird species.

Droppings tell all

Over the next four years, his team will collect and analyze bird droppings from more than 70 organic vegetable farms in Washington, Oregon, Idaho and California.

“I don’t think anyone has had the resources to do a study that’s as comprehensive and on such a large, regional scale before,” he said. “We’re really excited about it.”

Molecular analysis of bird droppings will identify what types of insects the birds are eating as well as the types of pathogens and parasites they carry that are important to human and livestock health. The scientists will use this information to quantify the risk of birds spreading diseases that endanger food safety.

Science-based food safety guidelines

The goal of the research is to inform the development of food safety guidelines, known as good agricultural practices or GAPs, using evidence-based information.

Meeting existing GAP guidelines can be costly for organic farmers who feel pressure to remove hedgerows and other types of habitat that support wildlife in order to reduce food safety risks. But removing habitat can harm the ecology of areas that support beneficial wildlife, and there is little evidence that the practice improves food safety.

“You need scientifically-based evidence on why you’re doing something to avoid moving forward in a panic,” Snyder said.

He said that GAPS are rarely based on rigorous, on-farm research demonstrating that they benefit food safety.

Farmer access to bird information

He also said surprisingly few studies document the pest-control benefits birds provide in U.S. farming systems, and most studies that do are from tropical regions. At the same time, few studies have looked at the role birds play as disease vectors across different types of farming systems and regions.

Working with the Cornell Laboratory of Ornithology and The Nature Conservancy, the project will adapt existing electronic bird management tools for famers so they can easily access farm-specific recommendations for wild birds.

In addition to Snyder, the WSU research team includes Jeb Owen, entomology and Thomas Besser, veterinary microbiology and pathology. Researchers from the University of California, Riverside and Oregon State University will also be involved.

###