The first week of September we began initial trials on Vortex Ring Accelerator (VRAD) technologies, on a 300 acre pistachio orchard near Bakersfield, California. The terrain at this location is quite hilly so visibility issues were somewhat limited. We were primarily tasked with keeping infesting flocks of crows from damaging the pistachio crop.
As you can see from the following photos, the VRAD is not a canon. It is something far more impressive and effective. The Vortex Ring Generator actually produces a Vortex Ring that acts as a projectile traveling through the air. In addition to a fierce concussion, an intense “bang” and a shock wave, the vortex ring travels through the air ringing and screaming past the point where humans can hear it. A vortex is formed when fluid (the fluid in our case being air) flows back on itself, making a spinning ring around an invisible core. The vortex ring produces little resistance as it moves through the air allowing it to travel long distances. The Vortex Ring acts as a projectile and may actually hit birds (without harming them) adding to the fear level.
Flocks of crows were coming into the pistachio trees in the morning hours so we arrived early and began actively looking for crows. The pistachio grower is currently using propane sound cannons as the primary defense which is ineffective. When crows land close to the propane canons and the canon fires the birds may flutter into the air 10 feet or so and fly immediately back into the pistachios.
We observed crow flocks in large numbers of anywhere from 25 to 200 birds. The major force was landing in the trees to the northwest and when we had the opportunity to get a good shot at these birds. There were about 100 birds present. We saw them land and were able to bring the VRAD to about 200 yards from the center of the flock. We raised the VRAD over the top of the crop, approximately 18 feet high and let the it blast over the top of the trees. We saw an immediate about-face as the birds flew full speed away. Interestingly there was another flock of 25-50 birds in a younger stand of pistachios at somewhere between ¼ and ½ mile in distance that we could not see and did not know were present. At about the count of 4 the vortex ring passed these birds and we saw them bolt as well. We were quite amazed at the distance.
For the next hour birds continued to filter back into this area, coming from all directions. We repositioned the VRAD and took three shots about 6 seconds apart. These birds left the area and gathered into a large flock off the property and began to circle in a thermal. They were barely visible but we took some very long-distance shots and were able to move them even further off till they were out of sight.
We did have the opportunity to fire directly at some hawks which were immediately phased by every shot, especially when the vortex ring came very close, but not to the same degree as the crow. Birds that were circling would turn away and then come back until about the third shot. After that they had enough and left the area. We were able to shoot in front of one hawk which, when the vortex ring passed in front of it, put on the brakes and seemed to try to stop in the air.
We had another flock of crows – maybe 100 - show up in force riding a thermal over one of the hillsides. We were able to get the VRAD into position to fire into the center of the flock at about a half-mile. Although the birds did not seem to “jump” at the shots fired, they did rise higher and higher in an attempt to get away. We kept shooting as they rose to the point where, rather than leaving as a group, they disappeared one by one, almost seeming to dissolve out of sight. Any flock of birds within 1000 feet left immediately upon firing.
Overall the success was very good. We were able to keep every bird off the 300 acres and this was using a test generator on a lift so were moving very slowly. Commercial versions will be nimble and very functional with regards to direction and altitude adjustment. In addition, we were operating in a very reactive manner trying to see and film the bird's reactions.
(We needed better filming equipment to show birds at any distance)
Our conclusion was that if we were going to manage a crop for birds we would take the VRAD around the perimeter and proactively shoot appx every 100 yards or so which would stop them from even coming in.
Also coming soon – Sonic Nets