Why Winemakers are Turning to Falconry to Tackle Pests

Napa Valley vintners are finding this tried-and-true deterrent more effective than modern technology

As a professional falconer, Rosen has trained all of her birds, which now number close to a dozen. Her brood includes Ziggy, a hybrid prairie-gyrfalcon. Jon McPherson for Napa Valley Vintners

It is late summer afternoon, and a sudden silence descends upon Bouchaine Vineyards in California’s Napa Valley. Moments earlier, a trio of songbirds sat chirping and pecking away at a cluster of ripe Chardonnay grapes that dangled from the vine at the 84-acre wine estate. Now the only sound is that of their wings flapping in the afternoon breeze. The reason for their quick departure is soon apparent as a falcon swoops down from the cloudless sky and lands on his master’s forearm, which is sheathed in a thick, elbow-length leather glove.

“Good job, Ziggy,” Rebecca Rosen tells the bird. As a reward, she produces a chunk of raw chicken, which the falcon devours in a single bite.

Rosen is a falconer and owner of Authentic Abatement, a firm specializing bird-control services in Napa Valley that counts a half-dozen vineyards in the area among its clients. Her falcon Ziggy is a “lure bird,” meaning his job is to scare off pest birds like starlings from the area—not hunt them. Rosen has trained Ziggy—a hybrid prairie-gyrfalcon named for the classic 1972 song, album and alter ego of rock legend David Bowie—to follow a piece of leather attached to a length of cord that she swings back and forth over her head. The lure’s movements mimic that of a bird, driving the falcon to do multiple sweeps of the vineyard.

“I love the relationship I have with the birds,” Rosen explains. “They have become my family when I’m away from mine.”  

The vineyards love Rosen’s birds, too—and running one is no joke: Here in Napa Valley, the heart of winemaking country, wine sales bring in more than $13 billion each year, meaning the stakes are sky-high for vintners to protect each lucrative harvest. Vintners find themselves in a near-constant battle with insects, disease and other pests that threaten their business. Among the more persistent threats is that of grape-gobbling pest birds, which treat vineyards as an all-you-can-eat buffet and pose the risk of decimating entire crops, all in relatively little time.

Over the years, vintners have turned to a variety of newfangled deterrents to prevent that from happening—including noisy air cannons, ribbons of mylar tape, netting draped over the vines, speaker systems, even air dancers (those waving inflatable tubes you're likely to find gracing auto dealerships nationwide). But some are returning to a time-tested method that doesn't require fancy tech at all: falconry. The ancient avian sport, which is thought to have begun in the Far East around 1700 B.C., later came to be called “the sport of kings.”

In recent years, several falconry companies have sprouted up in the area as demand for driving out pests has continued to increase. It turns out that despite modern advancements, there’s nothing quite like a scary predator bird to keep other birds at bay—for good.

“Falconry is the one thing that no bird is going to get accustomed to,” says Rosen. “The last thing a bird wants is to be eaten.”

During each session, Rosen uses a lure to encourage her falcon to continue sweeping the vineyard to ward off pests. Jon McPherson for Napa Valley Vintners

Glenn Stewart, who directs the Santa Cruz Predatory Bird Research Group, part of the Seymour Center at Long Marine Lab within the University of California, Santa Cruz, has spent years working with peregrine falcons and other birds of prey. To Stewart, it makes sense that modern technology hasn’t yet devised a deterrent more effective than these natural predators.

Over the course of “thousands of years, something has become imprinted in [pest birds’] DNA,” he says. “It may not be the most scientific expression, but they know deep within their being that the wing beat and silhouette of a falcon is dangerous to them. They don’t even have to be caught or attacked, they just see the wing beat and silhouette over and over again, and they decide to go eat someplace else. That’s why [falconry] works. It’s a biological fact of life, that they are fearful of the falcons.”

Rosen has been practicing falconry for the past decade. After becoming a licensed falconer, she began driving out pests while under contract at area military bases and landfills. Ultimately, she shifted her focus to vineyards. Each year, she makes the 12-hour drive from her home base in Arizona to spend several months in California during harvest, often camping out at vineyards so she and her birds are ready to strike come sunrise. Her brood is nine birds strong, including both hybrids and peregrines, all of which she trained herself. 

During the harvest and the months leading up to it, the 34-year-old falconer pays visits to each property multiple times a week. Autumn is when the multi-billion dollar Napa Valley wine industry begins production, and is a pivotal time for most wineries. That makes it all the more pressing for vineyards to protect their crops from pests in this final stage.

Among Rosen’s devoted clients is Toby Halkovich, director of vineyard operations at Cakebread Cellars, located in Rutherford, California. Halkovich manages the 43-year-old winery’s 560 acres of vineyards, which are spread across six parcels of land throughout the valley. He says that Cakebread has been working with Rosen for the past several harvests, and had first learned about her services through word of mouth. (Rosen admits she’s found all of her clients this way.)

“We figured that if she’s professional enough to work at U.S. Air Force bases, that she’d meet our needs too,” he says. “She drops by a few weeks before harvest when the fruit starts getting sweet. In order for it to be effective, the birds we’re trying to chase out need to think that she is there all the time. The worst one is the starling, because it reproduces quickly and in high numbers. Plus, it has a high appetite for grapes. We’ll sometimes see millions of them in the valley.”

Rosen visits vineyards in Napa Valley with her falcons to rid them of songbirds, which like to snack on grapes. Jon McPherson for Napa Valley Vintners

Halkovich estimates that in the time that Rosen has been visiting Cakebread, he’s seen an 80 to 90 percent decrease in avian pests compared to years in which he’s used other types of deterrents. Falconry is “very effective,” he says. “The first time she came here, I had the opportunity to watch, and it was amazing to see how many birds scattered once they saw her falcon.”

Chris Kajani, general manager and winemaker at Bouchaine Vineyards and another one of Rosen’s clients, agrees. Kajani has seen a 40 percent decrease in unwanted birds within the first month of hiring her earlier this fall. “I’ll be working in the vineyard and as soon as the birds spot her Toyota pickup truck rolling in, you’ll see them rise up from different parts of the vineyard and fly away,” she says. “They’ve started to associate her truck with the falcons.”

So what is it about falconry that has made it one of the most resilient tools of pest abatement among vintners? Stewart, a fellow falconer, thinks he has the answer. “I’ve seen air cannons in action and I’ve even seen vintners use speakers where they play the recordings of starlings … and I’ll see [pest] birds walking around on the ground nearby,” he says. “You can have the sounds, but there are no consequences for the birds. The cannons may scare them away at first, but they soon learn that there are no shotgun pellets that come with, and within a few weeks they adapt and become used to it.”

But claws, talons and an ominous wingspan silhouetted against the sky—few birds can get used to that. Which is all the more reason for Rosen and her falcons to make the long drive to California each year. After all, this year's harvest is depending on them.

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