The popularity of growing blueberries continues to rise, but this delicious fruit attracts flocks of hungry birds. These visitors can decimate a crop in a matter of days, often targeting the berries just as they reach peak ripeness. Protecting your harvest requires proactive planning and the deployment of tools designed to exclude or frighten birds away. This guide outlines strategies, from physical exclusion to sensory manipulation, necessary to ensure a successful blueberry yield.
Physical Barriers: The Most Reliable Defense
Exclusion netting is widely considered the most effective defense against birds, as it physically prevents access to the fruit. When selecting a net, the material and mesh size are important for both durability and effectiveness. High-density polyethylene (HDPE) netting is preferred over polypropylene (PP) because it offers superior UV resistance and a longer lifespan, often lasting five or more seasons.
The ideal mesh size for blueberry protection is around 1/2 inch (1.27 cm) or 15 millimeters. This dimension is small enough to exclude common fruit-eating birds like robins and starlings, while allowing adequate sunlight and air circulation. Nets with a smaller mesh size, such as 1/4 inch, may be necessary for very small bird species, but they can limit airflow. For maximum protection, the netting should be supported by a frame or cage built from materials like PVC piping or tall posts, creating a reverse aviary around the bushes.
It is crucial that the net does not rest directly on the blueberry canes or fruit clusters. Birds can easily perch on a draped net and peck through the mesh to reach the berries beneath. Elevating the netting with a supportive structure maintains a gap between the barrier and the fruit, rendering the birds’ pecking attempts unsuccessful. The perimeter of the netting must also be secured to the ground using clips, bricks, or soil to prevent birds from walking or tunneling underneath the barrier.
Sensory Deterrents: Scaring Birds Away
Deterrent methods that target a bird’s senses, such as sight and sound, offer a non-contact alternative to physical barriers. Visual deterrents exploit a bird’s excellent eyesight and fear of predators or sudden movement. Reflective materials, such as holographic Mylar tape or old CDs, create unpredictable flashes of light as they move in the wind, signaling danger to the birds.
Predator decoys, typically modeled after owls or hawks, trigger an instinctive fright response in smaller birds. For these static tools to remain effective, they must be highly visible and placed strategically within the blueberry patch. Some commercially available decoys incorporate moving parts or reflective eyes to enhance their perceived threat level.
Auditory deterrents, including electronic devices, broadcast distress calls of pest birds or the sounds of their natural predators to make the area seem unsafe. Propane cannons, which create a loud, sudden noise, are used in larger operations, though their effectiveness is often short-lived. Growers using noise-producing deterrents should always check local municipal noise ordinances to avoid conflict with neighbors.
Strategy and Timing: Preventing Bird Habituation
The long-term success of any bird control program depends on counteracting habituation, where birds become accustomed to a static threat. Birds are intelligent and quickly learn that a motionless owl decoy or a repetitive sound poses no danger. To combat this, sensory deterrents must be moved to a new location every few days, creating the illusion of an active predator or a constantly changing threat environment.
Timing the deployment of deterrents is equally important; they must be put in place before the fruit ripens and birds establish a feeding pattern. Birds typically begin to target blueberries when the fruit starts changing color and the sugar content increases. Installing deterrents at the first sign of this color change prevents them from associating the blueberry patch with an easy food source.
An effective approach is found in Integrated Pest Management (IPM), which stresses combining two or more distinct methods. For instance, using exclusion netting (a physical barrier) with reflective tape (a visual deterrent) creates a multi-layered defense. This integrated strategy, which may include netting for the main crop and a rotating visual deterrent on the perimeter, provides the most robust protection for the blueberry harvest.