The Birds. The Hazards. The Controls

THE BIRDS
Pigeons, sparrows and starlings are the three birds most commonly implicated in contamination in and around processing plants. Because they are also unprotected species under federal law, the hazards of these pest birds can be controlled. As with any pest control program, the first step is identification.

Pigeon

European Starling

House (English) Sparrow

Identification: Usually blue-gray with two dark bars on wings, approximately 11 inches long.

Seasonality: Births peak in spring and summer; pigeons are active year round.

Feed on: seeds, grain, livestock feed and manure, discarded food.

Overview: The feral pigeon adapts well to man-made environments and can be extremely troublesome. With the abundance of shelter that is provided by buildings, the pigeons have ample place to roost, loaf and nest. In such areas, food and water is often abundant, and when not, pigeons will fly to rural or undeveloped areas within flight range.

Identification: Purplish-green iridescent in summer and brown with white spots in winter; approximately 7 to 9 inches long.

Seasonality: Births occur in spring and summer; birds are active year round.

Feed on: fruits, seeds, grain, insects, livestock feed, discarded food.

Overview: Starlings are raucously vocal at roosting time and cause filth with their feces and nesting materials. Thousands may roost side by side, forming solid rows of birds on buildings or trees. They nest on/in buildings, lighted signs, marquees, billboard bracing, hollow lamp posts, soffits, exhaust ducts and vents.

Identification: Bright (male) or dull (female) brown with dark streaks on back and wings and grayish underparts; approximately 5 to 6 inches long.

Seasonality: Births begin March/April in the North; birds are active year round.

Feed on: fruits, seeds, grain, insects, livestock feed, discarded food.

Overview: House sparrow nests are built in/on gutters, vents, lamp poles, rafters, ledges—virtually any elevated, sheltered spot. The prolific house sparrow is largely dependent on humans for food and nesting sites. Nests built inside warehouses and under roofs and awnings cause contamination from nesting materials and droppings.

THE HAZARDS
The greatest hazard at a processing plant, said Cameron Riddell, president of Bird Barrier, is the potential of waste from their droppings or nesting coming into contact with the food at any point, including incoming raw goods, storage, processing, packaging, finished product and in or around the transportation vehicle. “There are five or six places along the way where birds can leave their mark,” Riddell said.

Known disease carriers for years, the Avian Flu outbreak increased the attention on birds as carriers and the spread of disease through their droppings, said Bird Buffer President Gary Crawford. “The longest known disease caused from birds, their droppings and dried droppings that become airborne, is Salmonella,” Crawford said.

Contamination can be wrought not only from fresh droppings, but also dried droppings that get sucked into air conditioning or heating vents and control systems, then spread throughout a facility, said Cory Gellerstedt, president of Nixalite. The birds may also carry bird mites and parasites, that can contaminate product.

More than 60 transmittable diseases and parasitic organisms can be attributed to birds. In addition to salmonellosis, a few are histoplasmosis, listeriosis, meningitis, encephalitis, streptococosis, toxoplasmosis, trichomoniasis, typhoid and vibriosis.

In addition to the disease potential of food contamination from droppings, said Rich Martin, Bird-B-Gone senior bird control engineer, are slip or fall risks, equipment damage, clogging of roof or floor drains, and even deterioration of employee goodwill due to the unsanitary conditions.

A major problem with the pest birds is that once they find a place with adequate food, water and shelter, they will stay. And once there, Riddell said, “birds have a daily routine just like people do.” They will go for breakfast in one spot, dinner in another and social interaction in a third.

Birds can be very intelligent. Martin gave the example of a flock of sparrows that would sit in a tree near a food plant dock. They knew that when trucks came in, the doors would be opened. So the birds would wait, then descend onto the trucks and in through the doors of the plant.

“Health inspectors are quick to shut down a food processing plant if nuisance birds are found inside,” Crawford said. Besides direct contamination, the airborne spores from drying feces can settle on exposed food and transfer disease. “Several thousand cases of food poisoning every year are attributed to this disease transmission route.”

THE CONTROL
Elimination of pest birds is best accomplished through a three-step process: inspection, correction, control.

Inspection. The first thing that should be done is a site evaluation, Gellerstedt said. Inspect for nesting, roosting, loafing and feeding sites, then determine what is attracting them. “With food processing, a lot of it is that there is a byproduct being extracted from the facility,” he said.

“Inspection is the key, just as in general pest control,” Martin agreed. The inspection will identify the bird species and its habits­—both key to control. “A lot of it will depend on the type of bird and the birds’ habits,” he said. From there, it is important to assess where the birds are congregating, inside or out.

When inspecting, Riddell said, “Be proactive. Look at the whole situation, not just one spot.” Once the main concentration or favored spot is found, don’t end your inspection, he said, the main attractant may be elsewhere. Instead, track the birds’ routine—find out where they are getting food and water and where and how they are traveling in and outside the plant. Knowing the points of entry the birds are using will go a long way toward excluding them in the future.

Correction. Once the bird species, habits, attractants and points of entry are determined, it’s time to take corrective action to address the problem, including:

• Eliminate food and water sources. The most important aspect of pest bird prevention is reducing or eliminating food and water attractants. “Bird problems can be solved almost 100 percent just by cleaning up food or water,” Riddell said.
• Clean up. “Birds are attracted to their own waste, so proper clean-up is extremely important,” Gellerstedt said.
• Protect points of entry. Prevent entry to food plants by screening or netting vents, caulking gaps around pipe chases and holes; and using vinyl strips or air curtains on doors.
• Maintain sanitation. Small amounts of food and water can sustain a bird, so sanitation is critical to keeping flocks from making their home in and around your facility.

Control. The most effective control method will depend on the bird species and facility design, but common methods of control are netting, spikes, baits and fogs or vapors.

• Netting – used to prevent birds from entering, nesting or roosting, netting should be of good quality with holes no larger than 3/4 inch, Gellerstedt said. Otherwise, small birds can get through and thrive in the safe haven.
• Spikes – placed on ledges, window sills, lighting, parapets and roofs, spikes deter birds from landing and roosting.
• Fogs and vapors – Fog and vapor dispersal systems can clear or reduce bird populations in large areas. A new technologies is the use of Methyl Anthranilate. Although repellent to birds, it is a naturally occurring food-grade compound. The tiny particles of the grape concentrate irritate the birds’ breathing systems, so that they leave and, over time, remember the irritant and avoid the area altogether.
• Baits – One form of bait works as a chemical frightening agent. Containing an acute oral toxicant, it causes the birds to emit distress and alarm cries and visual displays that frighten the flock and cause it to leave the site. Newer technologies also include a “birth control” bait for pigeons. When a bird eats the treated bait on a daily basis, the hatchability of its eggs is decreased and the population is gradually reduced. Both are restricted use pesticides.

“Birds can be as hazardous to your facility as rats,” Riddell said “It is important to deal with birds humanely, but they should not be tolerated just because they are birds.” d>