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New Blackbird Studies in N.D.

Wednesday, March 25, 2020
filed under: Birds

Millions of blackbirds make their way across North Dakota every fall, and each year those blackbirds cause big headaches for many North Dakota’s sunflower growers.  Some estimates suggest blackbirds cause more than $3.5 million dollars in damage to sunflower fields in the state every year.

There are many tools available to producers to help with blackbird management, but three new research studies planned for 2020 could provide even more tools and solutions.  The projects are all being completed by graduate students under the supervision of Dr. Page Klug, research wildlife biologist at the USDA-APHIS-Wildlife Services, National Wildlife Research Center’s North Dakota Field Station.

“Our goal with these projects, and really, all the research we do on blackbirds, is to reduce the damage blackbirds cause to sunflower,” says Klug.

The projects include using tools that already exist, including weather radar and drones.  Below, the investigators share details and goals of their projects, as well as how producers can help. 
Can repellent-spraying drones increase negative stimulus on large flocks?
Mallory White

Mallory White wants to find out.  The North Dakota State University graduate student has worked with unmanned aircraft systems, also called UAS or drones, in the past and has seen how they work — and don’t work — at getting blackbirds out of sunflower fields. 

“We have learned that we need to create a negative stimulus for more birds in the flock, which would ideally cause more birds to leave the sunflower fields,” White explains.  “To do that, we want to modify the drones so they can spray methyl anthranilate in the areas of the field being actively damaged by birds. Methyl anthranilate is an avian repellent, which means if birds come into contact with it, there should be a negative reaction and hopefully they will leave the field.  Methyl anthranilate irritates the birds — especially when it comes into contact with their eyes and beaks.  It can help us make the sunflower fields less attractive to the birds.”  

White plans to conduct field trials in 90 different fields across central North Dakota.  In 30 fields, she’ll use drones to spray methyl anthranilate; in another 30 fields, drones will spray water; and in the remaining 30 fields, she’ll simply fly the drones. 

“I’m hoping to discover whether spraying the chemical actually helps to disperse the birds from the areas of  heaviest damage,” she says.

White is still looking for producers to take part in her field trials.  She’s especially interested in working with growers in the central North Dakota counties of Burleigh, Emmons, Kidder and Logan. Her trials will begin around September 1 and conclude by October 30.  She will spend the winter analyzing the data and hopes to have a potential solution that will make drones more effective and give producers a new tool.

“I hope to be able to share with growers the results of this study; and if we see good results, share with them the best strategies for spraying the chemical, as well as how best to approach the fields and the flocks using drones.”

“Methyl anthranilate is a registered product and one producers are already using,” Klug explains.  “They’re applying it to their entire fields, and the downside of this repellent is that it is pretty much ineffective after the first rain.

“By spraying it from the drones, we can take a more-targeted approach and reduce costs by applying it only where it’s needed.  That’s an attractive part of this approach. 

“While methyl anthranilate is a registered product, and although we have an EPA exemption to use it in this study, we can’t use it on organic fields,”?Klug notes.  “But we could still include organic fields in our work; we would spray water or just fly the drones in those fields.”

White and fellow NDSU student Morgan Donaldson will be sending a survey to all North Dakota producers after the 2020 harvest (January 2021).  White is especially interested in not only recruiting growers to help with her work, but also to hear growers’ perceptions of drone use on their property.

“I think that’s an important piece as we are evaluating new tools and their effectiveness.  It’s important we hear from producers themselves,” White adds. 

“It is an innovative idea and a potential dynamic solution to a very big problem for growers,” says Klug. 

To learn more about White’s research, or to participate in her field trials, contact her at
What can we learn from the landscape ecology of bird damage?
Morgan Donaldson

Morgan Donaldson just started graduate school at NDSU?in January and is eager to visit with producers about the bird damage they experience, and to try and make sense of the damage patterns. Her ultimate goal: to create a risk map to help producers better plan when and where to plant sunflower.

“We want to encourage producers to grow sunflower. This map will provide insight into where the best places to plant ’flowers are — and even how to make the crop work in high-risk areas,” explains Page Klug.

The next step for Donaldson is the in-field survey she will be conducting this fall.  She is not only looking for fields where she can conduct her research — she’s aiming for 70 fields in North Dakota — but she’s also interested in producers’ damage estimates.  The mail survey from Donaldson and White will also be asking for producers to report estimates of bird damage to their sunflower crop.

“I’m looking for producers who will allow me to do damage estimates on their property.  I want to compare my in-field data with theirs.  I’ll take my data and theirs and look at the surrounding landscape, in-field variables — everything that may be correlated with the bird damage,” Donaldson says. 

“The comparison of producer estimates of bird damage to the in-field estimates will potentially yield insightful information that can be used for evaluating tools, as well as economic impact, at broader scales.  The idea is to create a map that shows what areas are most at risk of blackbird damage if you plant sunflower.  I also want to provide ways to help producers keep sunflower in their rotation, even in high-risk areas.”

That may mean planting early or growing a faster-maturing variety to allow early harvest and thus avoiding the largest flocks of blackbirds.  

Donaldson will do her in-field work from September 1 to October 30.  She hopes to focus her research on North Dakota counties that have had the highest bird damage in the past, but is willing to include fields anywhere in the state.  If you’d like to be a part of her study, contact her at  
Can we use weather radar to track blackbird roosts?
Bonne Clark

The Next Generation Weather Radar (NEXRAD) is a great way to track storms and precipitation; and, it could also help track blackbirds.  There are about 160 of these radars across the U.S. including one in Bismarck, N.D.

“When you watch the weather on television, meteorologists have scrubbed out the other stuff in the air, including birds,” explains University of Oklahoma graduate student Bonne Clark.  “We are scrubbing out the weather and looking at the other biological scatterings in the atmosphere. 

"The problem is, we can’t tell for sure on the radar what species of birds we’re detecting unless we compare radar images to on-the-ground bird counts. Weather radar can’t detect what species or body size you’re looking at; but it’s still a helpful tool for tracking large flocks of birds.”

 “This is a great example of using a tool that already exists for a different purpose,” adds Page Klug.

Clark will focus her research on a roost near the McKenzie Slough, just east of Bismarck.  The NEXRAD system has approximately 20 years of archived data. According to these data, this roost at McKenzie Slough has been occupied by blackbirds for eight years. 

“In mid-September of 2019, there were 20,000 birds.  By the end of October, the roost had grown to 400,000 — and then

This year, they’ll use radar as a method to count blackbirds at this roost. The radar will provide producers with new information about when the birds arrive, when they reach peak numbers, when they depart.  This is the first time that weather radar has been used for blackbird research.

“Weather radar has been used to detect purple martins and other flying  species.  Airborne animals are easy to detect on radar when they fly high and the radar beam can detect them,” Clark notes. “Blackbirds are not as  easy to detect. They have to be very close to the radar system because they don’t fly as high as other species.  But, we think radar can still help us track the roost and provide a better seasonal timeline  for producers.”

Much as meteorologists use radar to predict weather events, Clark says radar might also be used to predict bird movement.  And that can help producers plan their planting and harvesting dates to avoid large flocks of blackbirds. 

“There isn’t a lot known about the distribution of blackbird roosts or how blackbird numbers accumulate over the season,” Klug observes.  “This radar project looks at what point in the season bird numbers really grow and reach their peak. If producers know this, we can encourage them to plant early, plant early maturing hybrids, and get their crop harvested before major bird damage occurs.  

“This research will help identify that ideal harvest date to avoid yield loss from birds.”

There are limitations to the radars, however.  In states like North Dakota, there aren’t as many weather radars as in other states, for example.  But Klug anticipates more could be coming down the road.  “There is a push to have more radars installed across the entire country,” she says.  “So, there could be more radar locations coming, which would be helpful to understand blackbird flock movements and timing across the state.  We want to give producers the information they need when they’re planning their crops and their plant dates.”

To learn more about Clark’s research, contact her at
Survey will help with this research — and more
All North Dakota sunflower producers will receive a survey in the mail after the 2020 harvest (January 2021).  There will also be an online version available and that website will be shared by the National Sunflower Association once it is ready. 

The survey will include questions specific to these research projects, as well as general questions about blackbirds and blackbird management.  Klug says producers are asked to share information about the blackbird management tools they use, what works, what doesn’t work, and if they would plant more acres of sunflower if they did not experience blackbird damage.

“We really want to get some honest feedback from growers.  The better informed we are, the better equipped we are to develop research projects that provide  answers and solutions for growers,” she emphasizes.  — Jody Kerzman             
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