#25: Critters #3: Grape Farming is “For the Birds”!
April 1, 2023
Critters #3: Grape Farming is “For the Birds”!
Last month we chatted about Big Bird…(not the Sesame Street variety, but our nefarious Wild Turkey). This month, we’ll cover a much smaller bird that is a lot more plentiful…the common starling.
There are many different species of birds that can cause damage to a vineyard, but the bird responsible for the biggest grape crop loss in the wine country is the European Starling (Sturnus vulgaris). And, once again, it is yet another critter that was unwittingly introduced to our area by well-meaning folks.
Unwittingly introduced?
Yep. It seems that around 1890 a New Yorker named Eugene Schieffeling and his pals had a plan to introduce all the animals mentioned in the works of William Shakespeare to Central Park. (No joke!) While some of the attempts failed (“Caliban” from THE TEMPEST being one of them) the imported European Starling found that Central Park was a terrific spot to set up nesting and call home. The first year, the Schieffeling Gang imported and released a small flock of 60 of the birds and the following year, 40 more. Starlings typically produce two broods a year of 4-6 birdies each, so do the math…. In a matter of a few years, the population simply exploded! The migratory birds reached the Rocky Mountains by 1940, our West coast by the 1960’s, and now the US population exceeds about 200 million of the critters. And guess what? European Starlings absolutely love to eat grapes! I’m sure you’ve seen massive flocks of them flying over vineyards toward the end of summer, almost in a Blue Angels formation. When the grapes hit about 15% sugar and are about three weeks away from being perfect for picking, the berries become irresistible to these pesky marauders. These are migratory birds, numbering in the millions, that travel to our area during summertime as our grapes are ripening, just in time for their breakfast, lunch and dinner.
What do starlings look like?
They are pretty hard to miss during summertime. The adults are about 6” tall with colorful plumage; the wings have a green hue, the tips ending in brown and they have pink legs and a yellow bill that darkens in the fall. Individually they are kind of cute and don’t look like much of a problem, but they can descend upon a vineyard like locusts, pecking at the berries…and once the berries are pecked at, they become harbors for rot and spoilage. And, if that’s not bad enough, while they are sitting on clusters and pecking at the berries, they also leave behind their souvenir droppings, rendering those non-pecked grapes un-usable.
How much of a loss are you talking about?
Our worst years were in the beginning before we got pro-active to discourage them. We had a yearly loss of about a 20% each year. That’s a lot of fruit lost to birds!
What’s the best way to keep the birds away from the berries?
The best way to do so, late in the season, would be to cover the vines and grape clusters with a plastic netting made specifically to keep birds away from grapes. It works very well but is costly to buy and install, difficult to hang on the vines and remove (the tendrils want to attach themselves to the netting) and it makes the testing of berries and eventual harvesting a bit of a nightmare. As a rule, we don’t net so we have to look elsewhere and be creative….
What do you do?
Since we don’t choose to net (I think it’s ugly) there are a myriad of other deterrents, many of which we have used here at GlenLyon at one time or another.
Thirty years ago (and with encouragement and instructions from our Ag Department) we built an elaborate “crow-trap” on a trailer to attract and capture the critters. That worked quite well, but then the Powers-That-Be decided that a crow-trap wasn’t very humane and they outlawed them. (My argument that fell on deaf ears? I was simply trying to reduce the starling population back to the original 100 Central Park birds!) When we retired our crow-trap, we tried putting up scarecrows (popular long before THE WIZARD OF OZ) and that seemed to work for about ten minutes until the birds got used to the inanimate fake-people and started nesting on them. We still use plastic barn owls on the end of vineyard rows and we also hang sparkling aluminum strips throughout the vineyard, both designed to scare the starlings, but neither seems to work for long. We also have three “bird-in-distress” sound machines powered by 12v batteries and that seems to work for a few days until the little fellas get used to the noise. (We actually had a starling nest built right on top of one of the noise machines.) Other grape farmers use propane powered explosive charges that sound like shotguns going off to scare the birds, but we figure that wouldn’t be appreciated by our neighbors. We also have built and installed two Kestrel nesting boxes, hoping that a homeless Kestrel family (a natural predator) will inhabit. (Thus far, we’ve had no luck in attracting a family.) Another technique (but costly) is to hire a “Birder” who brings out real, trained, predatory falcons. I saw a demonstration a few years back and once the unhooded and trained real live falcon took wing over the bird-infested vineyard, a zillion starlings took to the air and simply vanished. It was very cool to watch and was enormously effective. One falcon can supposedly control up to 500 acres, but (as I said) it is an expensive option.
What’s the best deterrent you’ve found?
For the last five years, along with everything else, we’ve been using kites made by “Falcon Crop Protection” (Google it!). These are kites that look like falcons and are attached by monofilament to the end of long poles. Any wind over 4mph, they take to the air and once the kite is airborne, it looks just like an over-caffeinated predator in flight. And, amazingly, the starlings don’t seem to get used to it since its flight pattern is so erratic. We now have three for our upper vineyard and two in our lower. Not only are they the best deterrent I’ve found, but they are really pretty to watch out on our Overlook!
For added protection, this season we are also going to try a new bird repellent called “Avian Control” that I wrote about last month. It is sprayed on the grapes and foliage around the circumference of a vineyard just before the starlings arrive and is advertised to be very effective. It is also organically bio-degradable, safe for humans and pets and lasts for about two weeks. Supposedly it also will help keep the wild turkeys away, so I’m going to try spraying it this season! (If it works, I’ll let you know!) Like most grape farmers, at GlenLyon we continue to use as many deterrents as it takes to try to keep the birds at bay.
That’s it for this piece. Next month, my last article on Nasty Critters: Gophers!
Squire Fridell, Whinemaker (NOT a typo)
“Great wine requires a mad man to grow the vine, a wise man to watch over it, a lucid poet to make it, and a lover to drink it”
Salvadore Dali