Vineyard Wildlife Control
Itís widely known that vineyards are vulnerable to a wide variety of pest birds. Several species of birds, including robins, starlings, mockingbirds, finches, and blackbirds are common pests of grapes. These birds damage fruit by plucking entire berries from the cluster or pecking holes in the berries (See Figure 26.1). Finches peck at berries and starlings consume whole berries. Starlings in particular have a voracious appetite for grapes so even small flocks can do considerable damage. Damage from starlings is sometimes mistakenly blamed on the bees that congregate on damaged clusters. Birds are daytime feeders and typically begin to feed on grapes when they develop color, which is before maturity. Much like humans, different birds are attracted to grapes for different reasons.
Acoustical repellents rely on sound to scare birds away. Birds have a hearing range similar to humans, so if people can hear it, birds can hear it. Unlike rodents, birds cannot hear ultrasonic sounds.
Propane-fired cannons cause birds to flee by producing loud, unexpected blasts. They are available in a wide range of configurations, from mechanical single-shot units, to fully electronic, randomized, rotating multi-shot units.
Electronic Sound Devices
Alarm systems that imitate bird distress sounds can also be located in the vineyard and will sound on a preset time schedule. Some of the more sophisticated systems can produce distress calls from different bird species, alternating the sound and length of time of each.
Pyrotechnic Pistol Cartridges
Pyrotechnics include a wide variety of noise-producing cartridges usually fired from a hand-held pistol and produce a loud, whistling sound throughout their flight.
Visual repellants are useful to in controlling birds in vineyards too; however, birds do not react nearly as much to visual deterrents as they do to acoustical ones. Birds are very capable of adjusting to new objects in a relatively short period of time.
Beach ball size scare-eye balloons have graphics representing the gaping mouth of a hawk have been effective worldwide. The yellow balloons appear to be more effective.
Streamers and Flash Tape
Streamers and flash tape are strips of shiny plastic tape which are strung over the vineyard.
Flashing Lights and Mirrors
Some bird species, notably starlings, are repelled by flashing lights and mirrors.
Birds of Prey
Some growers have tried to set up nesting poles to encourage falcons and hawks to nest in vineyards. When large avian predators such as falcons are active in the vineyard, fruit-eating birds such as startlings will tend to stay away from the area.
Vineyard netting (See Figure 26.1) provide a good barrier to feeding birds and offers virtually 100 percent bird protection, but is expensive and cumbersome to apply and remove. Nets that drape over the canopy are very common and come in a range of colors, mesh sizes, and widths. Consider the pest species when deciding mesh size; if only larger birds are causing damage, a larger mesh size (more affordable) can be used. Bird netting is available in a lightweight one-use formulation or heavier multi-use ultraviolet protected materials.
Federal Migratory Bird Treaty Act
The Federal Migratory Bird Treaty Act protects all birds except pigeons, house sparrows, and starlings. However, local ordinances may protect bird species not protected by the federal act and/or specify the types of treatments that can be used. Always check local and state laws before attempting to control any bird species.
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