Grackles are intelligent blackbirds recognized by their iridescent plumage and bright yellow eyes. Their highly social nature means they gather in large, noisy flocks that become a significant nuisance in urban and suburban areas. These communal roosts create excessive noise, especially at dawn and dusk, and generate substantial amounts of corrosive droppings. Dealing with a grackle problem requires a strategic approach that first addresses why these birds are attracted to your property.
Identifying the Problem and Eliminating Attractants
Grackles are highly adaptable omnivores, and eliminating their readily available food sources is the immediate first step. This means securing all outdoor garbage cans with tight-fitting lids and ensuring no pet food or livestock feed is left accessible outside, particularly overnight.
Homeowners who feed smaller songbirds must modify bird feeders to deter larger grackles. Switching from platform or tray feeders to tube feeders with very short perches makes seed access difficult for them. Stocking feeders with seeds that grackles dislike, such as safflower, discourages them from lingering. Grackles also seek out water sources, so eliminating standing water, repairing leaky outdoor faucets, and removing bird baths makes the environment less hospitable.
Grackles select dense trees and shrubs for communal roosting and nesting because the thick foliage provides protection from predators and the elements. Trimming branches to thin out dense canopies, especially in preferred roosting trees, reduces the cover these birds seek. This habitat modification makes the trees less appealing as a secure overnight location, encouraging the flock to relocate their roost.
Implementing Physical Exclusion Barriers
Installing physical barriers blocks grackles from specific structures or areas. Bird netting is one of the most reliable exclusion methods, especially for protecting gardens, fruit trees, or covering open areas like eaves and patios. For grackles, a heavy-duty mesh with a specific opening size of 1-1/8 inches is recommended to effectively block their access.
For commercial buildings or homes with flat ledges and beams, anti-perching devices can be installed to make landing impossible or uncomfortable. Bird spikes prevent the birds from gaining a foothold on building ledges, signs, and window sills. Alternatively, installing a low-profile, electrified track system, such as a Bird-Shock Flex-Track, delivers a mild but startling electrical pulse upon contact, deterring the birds from landing without causing harm.
Another exclusion technique for narrower surfaces involves the use of specialized wire systems that create an unstable landing area. These systems use thin, spring-tensioned wires positioned slightly above the surface, which are nearly invisible but make it impossible for the grackles to land securely. For structural features like soffits or beams, angled barriers, such as Bird-Slide, can be installed to eliminate the flat landing surface entirely, forcing the birds to slide off.
Utilizing Sensory and Psychological Deterrents
Sensory and psychological scare tactics are often employed to disperse grackles. Visual deterrents exploit the birds’ naturally wary nature by presenting them with perceived threats or startling flashes of light. Highly reflective, holographic Mylar tape, sometimes called flash tape, can be strung in trees or across open areas, utilizing both movement and intense light reflection to disorient and frighten the birds.
Other visual methods include using large, inflatable “predator eye” balloons or installing decoys that resemble natural predators like owls or hawks. Since grackles are intelligent, these static deterrents must be moved frequently to prevent the birds from becoming accustomed to them. Auditory deterrents are also effective, especially sonic devices that broadcast species-specific distress calls or the sounds of their predators.
These sonic devices should be programmed to play at randomized intervals, rather than a fixed schedule, to delay the grackles’ habituation to the noise. For ground-level foraging or roosting, motion-activated sprinklers provide an unexpected burst of water and movement that is highly startling to the birds. Finally, non-toxic taste aversions, such as liquid repellents, can be applied to trees or surfaces, which create an irritating taste or sticky texture upon contact, making the area undesirable for roosting or foraging.
Legal Considerations and When to Seek Professional Help
Any action taken to control grackles must be done with an understanding of federal wildlife law. All grackles are protected under the Migratory Bird Treaty Act (MBTA). This law prohibits the capture, injury, or killing of these birds, as well as the destruction of their nests or eggs, without a specific permit.
However, the MBTA includes a standing depredation order that allows for control measures when grackles are causing property damage, posing a health hazard, or affecting agriculture. Lethal control is highly regulated, generally reserved for agricultural situations, and must be conducted under the strict supervision of government agencies. Homeowners should focus exclusively on non-lethal deterrent and exclusion methods to remain compliant.
If a grackle problem involves a massive, established communal roost, or if the birds are nesting inside a structure like an attic or vent, it is time to contact a professional. Licensed wildlife control operators or pest management professionals have the necessary permits, specialized equipment, and knowledge of local laws to safely and legally relocate large flocks or perform complex structural exclusions. These experts can install permanent solutions like electrical track systems or industrial-grade netting that are difficult for an average person to manage safely.