NAPA (KPIX 5) — Intruders entering Napa Valley vineyards are threatening massive damage to the wine grape crop, but one woman and her small flock of helpers are standing in their way.

The grape harvest is well under way for wineries in the region and that’s an invitation to thousands of local and migrating birds to get an easy meal. It’s Rebecca Rosen’s job to make it a little harder.

“Her truck would pull up in the vineyard and, literally, you’ll see liftoff because they know what she has on her,” said Lise Asimont, Operations Director for the vineyards at Cakebread Cellars winery.

Rosen is a falconer hired by various Napa wineries to use her raptor friends to scare off the smaller birds. She swings a feathered lure, which the soaring falcons swoop down on. If they can grab it, they get a treat. After just a few minutes of this hunting behavior, most of the smaller birds in the area are willing to move along.

“Essentially, the more we fly, the more we train the wild birds to stay away,” said Rosen. “So, at a time when you would normally have, say, 500 birds in the grapes, after two weeks of intense flying the falcon, the bulk of them will move off so you’ll only be fighting 15 to 20 birds.”

Her raptors have different personalities. An aggressive peregrine falcon named Rambo is all business and Rosen calls him one of her “enforcers.” And then there’s E.B., a hybrid-breed falcon who is one of the more laid-back members of her flock.

“I can get more work out of these guys than the enforcers,” she said, “but the enforcers really make a difference when the birds are like, ‘Oh, your falcon’s not really serious.’”

But the job they’re doing is completely serious to Cakebread Cellars.

“You can actually lose your entire crop to a flock of starlings in a couple seconds or minutes. I’m quite sure of it. So, she’s incredibly effective,” said Asimont.

Rosena says birds are actually pretty lazy and prefer not to fly unless they have to. But she says that’s the reason her falcons are so effective in driving other birds away.

“Because the birds expend more energy running from the falcon when they can just, you know, go eat the neighbor’s grapes and not be hassled at all,” she said.

There are also wild raptors in the area and they have a similar effect. But Rosen says by focusing her activity on a specific vineyard, it makes that area off-limits in the minds of the other birds.

At Cakebread Cellars, the practice began more than two decades ago when its owners took a falconry class at a winery in Europe and brought the idea back with them. They’ve been doing it there ever since.

Rosen also gives public demonstrations of her raptors. The next “Falcon Experience” is scheduled for Nov. 10 at Bouchaine Winery.

Comments