Pest Bird Management Strategies
There are approximately 10,000 species of birds on Earth, and most rarely interact with urban structures. Overall, birds are considered beneficial species for numerous reasons including insect consumption, plant pollination and seed spreading, to name a few. Yet, there are some species of birds that are considered pests. This group of birds can adulterate food products, damage buildings with fecal deposits, and pose public health safety issues under the right conditions.
Retail stores, restaurants, grocery stores, food distribution centers and food plants can be negatively impacted by pest birds and the detritus they leave behind. Feathers, feces, nesting materials, ectoparasites and pathogenic microbes associated with these pest birds establish them as a notable pest, and their presence should not be tolerated.
Pest Bird Species
House sparrows (Passer domesticus), European starlings (Sturnus vulgaris) and feral pigeons (Columba livia domestica) were introduced into the United States and are not protected by federal laws. They are considered invasive species and can be removed without filing for depredation permits. However, some states or local governments may have more stringent bird depredation guidelines. It is prudent to review bird management programs with local authorities prior to developing a strategy to remove or eliminate these species.
Blackbirds (including grackles and cowbirds), woodpeckers, Canada geese, gulls (ring-billed and herring), cliff swallows and American crows are also frequently cited as pest birds. It is important to note that these birds are protected by the Migratory Bird Treaty Act and typically require permits when being managed.
Although bird management opportunities abound for pest management professionals, they frequently overlook or simply misunderstand how to manage birds that interact with commercial structures. Bird management strategies must be developed on a case-by-case basis as each building/facility is unique and will require an in-depth analysis to determine the best bird management practices. With experience, bird management professionals can become proficient at proposing and implementing effective pest bird management programs.
Bird Management Strategies
Bird frightening, physical removal, deterrents, and exclusion are all effective management strategies for pest birds. Each of these methods work under the right conditions, but many factors come into play when managing birds. For example, bird pressure, site fidelity and alternative roost sites are major considerations bird management professionals must understand to manage established bird populations. Can the flock be moved to other sites? Are the birds nesting at the site? How long has the bird population been established? The more information a bird management professional can collect up front, the more successful they will be when implementing a control method.
Bird frightening can come in many forms. In some cases, highly trained dogs are used. When moving Canada geese from sites, the dogs chase the geese away from their foraging, resting and nesting grounds. However, this needs to be done over a period of a few days and requires up to four weeks to condition the geese that the site is not safe for them or their offspring. Long-term resident geese are especially stubborn and usually require multiple harassment visits from dogs. Other forms of bird frightening include noisemakers, such as air horns, propane bird “cannons” and predatory bird calls. Each of these frightening tools can work, but the situation must be analyzed prior to their installation. More importantly, their limitations must be understood by the bird management professional.
For instance, predatory bird calls (termed bioacoustics by researchers) are one of the most frequently used bird harassment tools used by the general public. It is common for pest management professionals to arrive at a commercial client’s building and hear a predatory bird call system wailing in the background as the client purchased it online because they found a “good deal.” However, the effectiveness of these systems is limited, and they are usually improperly installed by the consumer. Simply installing a predatory bird call system that constantly streams multiple predatory bird calls is not effective as bird’s quickly condition themselves to the recorded calls. But, it is important to note, these systems can work for small sites and short periods of time (usually less than one week). Additionally, several manufacturers advertise their ultrasonic devices as effective bird deterrence systems, but there is little to no science to substantiate these claims. In fact, birds do not hear in the ultrasonic range so these types of devices will not scare birds or be effective. Buyer beware!
Some situations call for measures that are more drastic where the birds need to be physically removed from a structure. Even with the best-sealed structures, single birds do find their way into grocery stores, food warehouses, food plants and pharmaceutical manufacturers. Pest birds cannot be tolerated in these environments and must be removed as quickly as possible to prevent product adulteration. Mist netting and aggressive harvesting are two common methods bird management professionals employ in their day-to-day operations when birds find their way inside commercial buildings.
Mist net kits are comprised of two telescoping poles (typically 18-24 feet in length) that support a fine mist net between each pole. Mist nets vary in widths with 20-foot wide nets the most used. The poles have hooks and magnets to attach to trusses and other ceiling structures so the poles can be hung near ceilings in bird flight paths. Mist net kits can also be modified to be used at lower levels when birds are foraging near or at ground level. An experienced mist net installer can quickly catch and release birds unharmed, especially in smaller retail stores.
When mist netting is not feasible, aggressive harvesting, the use of high-end air rifles, is employed. It is oftentimes impractical to use mist nets in large distribution centers and food plants when the client needs the bird(s) eliminated quickly. Only experienced bird management professionals trained in the safe use of air rifles should be allowed to carry out aggressive harvesting measures. Clients must be involved in this process to ensure their personnel are removed from shooting areas and their employees are informed of the operation. Persons involved in aggressive harvesting must know state and local laws prior to using air rifles in commercial structures.
Aggressive harvesting can only be performed on house sparrows, European starlings or feral pigeons. All other bird species are protected, and therefore, state wildlife agencies need to be contacted prior to aggressive harvesting. Most states will require humane bird removal methods be exhausted prior to issuing bird depredation permits. As can be observed, personnel responsible for aggressive harvesting must be able to identify pest birds to species level to avoid public relation issues and potential regulatory fines.
Deterrents and Exclusion
Bird deterrents and exclusion techniques are also used by pest management professionals. Cable and turnbuckle netting systems, post and tension wires, shock tracks, ledge-altering slides and spikes are just a few of the exclusion and deterrent systems used by bird management professionals. Exclusion techniques, when feasible, provides the best long-term approach for pest birds especially in urban environments where bird pressures can be extremely high.
Cable and turnbuckle systems, when installed correctly, provide 100% relief from pest birds. Loading docks, canopies, and overhangs are ideal candidates for cable and turnbuckle netting system installations. It is important for clients’ to vet the competence of bird net installers prior to hiring them. Asking for references to review the outcome of previous netting jobs is crucial. Inexperienced or poorly trained netting installers can overlook or improperly install netting on corners, edges, and hard-to-reach areas where netting systems are vulnerable to bird intrusions. Poorly installed netting can result in dead birds inside nets, client complaints, public relations issues, and unnecessary, costly callbacks.
Shock track deterrent systems are another good option for high-pressure bird situations. Shock track can be installed on building ledges and edges where birds frequent. Parapet walls, exterior signage and ornamental facades are frequently bird-proofed using shock track systems. These systems are powered by solar charging units or direct plug in chargers. Those who choose these deterrents must remember that shock tracks use electricity and may not be suitable for every environment (e.g., distilleries, gasoline station canopies, dusty environments). Annual maintenance contracts should be included with shock track systems as they are prone to weather exposure and damage from contractors working near them.
Pest birds can be tricky in commercial buildings. Bird management professionals must be knowledgeable in bird biology and behavior, be astute observers, and understand how to design and implement bird management techniques based on site analysis and real-world experience. If done correctly, bird management strategies can provide cost-effective, long-term solutions for commercial clients to ensure protection of their goods, bottom line and reputation.
Dan Collins is Technical Director at McCloud Services. With over 25 years of urban pest management experience, Dan has lectured nationally and internationally on a variety of food safety and pest management topics. He also authored technical articles for Pest Management Professional and Pest Control Technology magazines and provides pest management consulting services nationally for the food and pharmaceutical industries. Visit www.mccloudservices.com to learn more.