The common raven (Corvus corax) is a highly intelligent and adaptable bird, often leading to conflicts with human environments. Their large size, noisy communal roosts, and opportunistic feeding habits can result in property damage, scattered garbage, and general disturbance. Deterring ravens is complex because their cognitive skills allow them to quickly learn and bypass static control measures. Effective management requires a multi-pronged strategy that first removes the primary attractions drawing them to an area.
Eliminating Food and Water Sources
The foundation of any successful raven deterrence strategy involves removing the resources that initially attracted the birds. Ravens are omnivorous scavengers who thrive on readily available food, making human-provided sustenance the primary draw. Unsecured garbage is a major attractant, so all outdoor containers should be heavy-duty and secured with locking mechanisms, bungee cords, or ratchet straps.
Pet food and livestock feed should never be left outside, as ravens quickly learn to exploit this consistent energy source. If pets must be fed outdoors, remove the bowl immediately after the animal finishes eating. Removing natural food sources like fallen fruit or accessible standing water from bird baths and fountains will also make the location less hospitable. Eliminating these incentives makes other deterrence methods far more effective.
Visual and Physical Deterrent Tactics
Deterrents that rely on sight and physical exclusion create an immediate sense of danger or an impassable barrier. Reflective objects are inexpensive and function by creating unpredictable flashes of light that disorient and alarm ravens. Holographic flash tape, old compact discs, or specialized reflective balloons can be hung in vulnerable areas.
The use of predator effigies, such as models of owls or hawks, can initially frighten ravens. However, these intelligent birds rapidly recognize static threats, so decoys must be moved every few days to maintain the illusion of an active threat. For physical exclusion, installing fine-mesh netting (such as two-inch mesh) over vulnerable areas creates a reliable barrier. On common perching spots, like ledges or roof peaks, installing specialized bird spikes or wires prevents ravens from landing comfortably.
Auditory and Active Hazing Methods
Methods utilizing sound and direct human intervention are designed to actively harass the birds and make the area feel unsafe. Specialized acoustic devices can broadcast recordings of raven distress calls or the sounds of their natural predators. For these devices to work on intelligent corvids, they must be set to play at irregular, unpredictable intervals to prevent the ravens from becoming accustomed to a routine.
Active hazing involves direct human interaction to reinforce deterrents, which is necessary because ravens quickly ignore static sound or visual threats. Simple noise makers, such as yelling, clapping, or the intermittent use of an air horn, are effective when coupled with a human presence. Directing a sudden stream of water from a garden hose toward the birds can also be used as a non-harmful harassment method. This active engagement teaches the ravens that the location is constantly monitored and presents a threat, rather than a predictable nuisance.
Maintaining Effectiveness and Legal Compliance
The adaptability of ravens means that any single deterrent will eventually fail as the birds habituate to it. To overcome this, a strategy of rotation and combination must be employed. Deterrent methods should be switched or moved frequently, such as alternating the placement of reflective tape with auditory calls. Combining a visual deterrent with an active hazing approach creates a multi-sensory attack that is difficult for the birds to ignore or anticipate.
Persistence is paramount, and immediate action should be taken the moment ravens attempt to return to a previously cleared area. Ravens are protected under the federal Migratory Bird Treaty Act (MBTA). This law prohibits the unauthorized “take” of the bird, including killing, capturing, or destroying active nests or eggs. Lethal measures or the removal of active nests are illegal without obtaining a specific depredation permit from the U.S. Fish and Wildlife Service.