Propane Cannons:  Can they be effective?

Of all the control techniques available, propane cannons create more questions than almost any other item.  They are loud, they are big, and they are often mistaken for something other than what they are.

A propane cannon operates as follows.  Propane flows from a tank through the hose and regulator into a chamber.  From the chamber, depending on the make of cannon, the propane is stored until enough of it enters the chamber and creates the pressure necessary to trip a combination of levers and springs.  When that happens the premeasured amount of propane is fed into the firing chamber of the cannon and a spark is introduced into the chamber causing a “big bang”. 

One of the common misconceptions about propane cannons is that they fire a projectile.  They do not.  An unsuspecting bird may become a projectile if they are investigating the barrel for potential nesting while the cannon is operating, however; this is very uncommon.  I have also heard propane cannons referred to as water cannons, air cannons and carbide cannons.  They do not fire water, however some models used compressed air to make a loud “pop” and earlier propane cannons used a carbide striking wheel instead of the current piezo electronic firing unit.

So, do they work?  Yes they do.  Maybe the better question would be, “Why aren’t mine working?”  Propane cannons are no longer effective after they have been left in the same place for two days.  You must move them every other day, even if you only move the cannon 100 feet.  The next step is to try to eliminate any firing pattern that may exist.  Zon propane cannons are single fire units.  They will fire one time every 45 seconds to 30 minutes, depending on the setting you have chosen on the regulator.  M-8 propane cannons are multi-fire units.  They will fire one to three times in a completely random order every 30 seconds to 40 minutes, depending on the setting you have chosen on the regulator.  Having a multi-fire unit doesn’t mean you don’t establish a firing pattern.  You still need to vary the firing times during the day.

When you think about a propane cannon you have to realize what your trying to do.  You’re trying to simulate gunfire.  The advantage a propane cannon offers is that you don’t have to be around to make it go off.  Bearing all this in mind, the most effective way to use a propane cannon is to know what times the pest birds are approaching the vineyard, and have the cannon waiting for them. 

The next item of consideration is the angle of approach and the area you are trying to protect.  Propane cannons have an actual effective range of 1-1/2 to 2 acres.  If you choose propane cannons as the only bird control measure you employ (please don’t), you’ll need them spaced around the perimeter as well as the interior of the vineyard.  The best choice is to place cannons in the interior of the vineyard and surround them with visual cues, such as flashtape or scare eye balloons.  Review the vineyard to decide which area traditionally receives bird damage first.  Then place your cannon(s) there on the perimeter and continue with the visual cues.

If you have ever tried to hunt crows you probably don’t need visual cues explained much further.  For those of you who haven’t, let’s say you’re on your first crow hunt.  After obtaining your depredation permit, if it isn’t crow season, you drive out in your white truck, set up and shoot crows as they come to wreak havoc on your crop.  After two days of doing this you notice that the shooting isn’t as good in the spot you’ve chosen, the crows are flying 200 yards to the south of you.  You move that evening and the crows move 200 yards to the north where you had just been shooting.  Why?  Because they can see the white truck.  The white truck is the visual cue. As far as the crows are concerned it’s the white truck that is shooting at them.  This is a basic hazing principal that works with most bird species; crows just happen to be the best example because they are often referred to as the “smartest” of the bird species.  The visual cues available to the grower vary from flashtape to scare eye balloons, hawk kites and even the traditional scarecrow.

So, back to the original question about propane cannons, “Can they be effective?”  Yes, they can, but in reality they are only as effective as your ability to relocate the cannon, vary firing times and change firing angles.  The worst mistake you can make with a propane cannon is to let it run 24 hours a day.  In addition to irritating your neighbors, you allow birds to become comfortable (habituate) with your cannon.  Once birds become habituated to the hazing techniques you are using they will cause considerable damage, no matter how many cannons, balloons, or rolls of flashtape you may be using.

Finally, a little maintenance is in order with propane cannons.  The moving parts need to be lightly oiled (too much oil attracts dirt) and the hoses inspected every season before use.  Surprisingly enough parts are readily available, even for cannons that are 15 years old.  They are easy to work on, once you’ve become acquainted with them, and can be easily maintained.

Good luck with those cannons.  Remember, they are worth the effort, and now is the time of year to get them in working order.