Blackbird damage is something that many sunflower producers deal with come harvesttime. With spring planting still on the horizon, there is still time to plan ahead to help protect sunflower crops

Page Klug is a research wildlife biologist with USDA in Fargo, N.D. In 2020, she updated a sunflower grower survey from 1997 discussing efficacies of blackbird repellents. The study was done in conjunction with North Dakota State University and the National Sunflower Association.

Klug says coordination can help keep damage to a minimum. Of the survey respondents, 78% said blackbird damage had an impact on their profits, with 65% saying cattail management is one of the “most effective ways to reduce blackbird damage,” she says. “You can manage your own cattail, but you can’t manage your neighbor’s.”

Cattail management falls under “landscape management,” where producers can manage things outside of the sunflower field to keep blackbird damage to a minimum.

Blackbird populations

Peak blackbird season in the Dakotas is mid-October, or at the height of sunflower maturity, Klug says. “In 2015, this overlapped with an early arrival of blackbirds, and stayed through the eight weeks of the damage period,” she says, with damage amounting to $40,000. “Roost numbers had peaked at 1.12 million birds, with maximum daily damages worth up to $2,000 a day.”

Krug advises producers to try their best to miss that highest population of blackbirds to save damage costs. “We asked if we could advance harvest two weeks — whether by desiccation or early planting or early-maturing varieties,” she says. “At one location, it was a $1,800 savings just to miss that peak blackbird damage season.”

If producers try to save damage costs with this route, planning ahead prior to planting can help.

Tools and methods

New technologies bring new opportunities and tools to keep blackbirds at bay. Aside from landscape management, producers can:

“Most of my research now is focusing on the efficacy of drones and their use in agriculture to stop bird predation,” Krug says.

Drones are being used in many agricultural or aquacultural operations to dispel predatory birds. “We’ve found that the birds respond to something that looked like a hawk, and it took more time for them to return,” she says.

However, drones come with battery limitations, and complete flock abandonment was found in only 25% of field trials.

Advantages are found with new drones though. “New off-the-shelf drones are easy to fly and can cut through a flock pretty fast, so you can create chaos compared to an RC [remote control] plane,” Krug says.

Drones also possess the availability to spray avian repellent in the form of grape skin extract, which led to higher flock reductions in test fields.

Trying to not be the first or last sunflower field to reach maturity can also be used to avoid extensive bird predation, Krug says. “Coordinating with neighbors can help make sure you’re not the only sunflower field in the area to spread out those flocks,” she says. “This helps to spread those birds out so that one producer isn’t hit the hardest, and helps spread those birds out across the state.”

While this method still shows blackbird damage, spreading the damage out among larger fields and producers helps minimize damage.

So what’s the best way to save sunflower crops according to Krug? “There’s not just one tool. In the end, it’s going to be an integration of multiple methods, compared to a single technique. Habitat and cattail management, coordinating with neighbors, it all works together.”

Find more information about this collaborative research study from NDSU Extension.