There are many tools to help manage the birds that can damage a farmer’s crops. With help from Dr. Page Klug, a research wildlife biologist with the USDA National Wildlife Research Center, we are offered a plethora of suggestions as to how to make it work safely.
According to Klug, “successful bird dispersal often involves a combination of tools.” Those include getting tools out early before birds establish feeding areas, understanding bird ecology and biology and, like every endeavor in life, exercising patience and persistence.
Klug places her methods into several categories: population control habitat and modification; exclusion; visual, auditory and physical deterrents; and chemical repellents.
“When you move to the landscape scale, that’s when we have more tools at our disposal,” Klug said. “Where we can start to impact bird distributions is by offering habitat modifications or alternative food resources in the surrounding landscape. This will influence where they’re choosing to forage, roost or make migration decisions.”
However, “this would require coordination with neighbors as landowners do not have the ability to implement methods beyond their own property boundaries,” said Klug.
But, she noted, where farmers have the most control is in the field where they can make decisions about what tools they use, the labor and the cost.
An example is chemical repellents to treat weeds or insects. While in the lab, Klug found you can reduce consumption by using methyl anthranilate. “When it contacts the bird, it will irritate the mucous membranes and have them not want to eat that that crop,” she said. However, “anthraquinone is gustatory, so it must be ingested to have an impact,” she added.
Although pesticides might work on some crops and in some situations, Klug said, she wouldn’t recommend any pesticides or chemical repellents that work for row crop agriculture.
There are several approaches to get the crops off the fields before the numbers of blackbirds are at their peak. Avoid planting vulnerable crops near roosting or breeding habitats, plant larger fields to spread the damage, coordinate with your neighbors, avoid early and late ripening fields, delay planting dates or you can try advanced harvesting.
Finally, Klug delved into the topic of drones, which have the benefit of not needing to work in conjunction with anyone living nearby. “In our captive studies, after utilizing raptor models versus a fixed wing or quadcopter model, we found individual redwing blackbirds will alert sooner and are more likely to take flight in response to a raptor model. They are also more likely to take more time to return to forage if you’re flying at them directly as opposed to overhead,” she said. They also noticed that abandonment peaked later in the day, likely because the birds were tired of foraging. Therefore, Klug concluded, using drones in the morning would likely be more effective.
by Jessica Bern