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Birds may be nature’s beautiful creations to the general public,
but not to the “dropped upon” maintenance worker, store,
employee, shopper...or property manager. Besides being unsightly, bird feces can also cause dangerous, slippery
walking conditions. Droppings are unhealthy — even potentially
fatal. More than 60 different transmissible diseases have been associated
with birds and their excrement. Droppings cost money, both in outlays
for daily cleaning and in lost business from customers who prefer
a dropping-free environment. Lastly, birds can be incredibly destructive. How to Control Bird Pests? Before flying headlong into a bird control program, step back and take a good look at the bird problem. No two bird infestation problems are exactly the same. Treat yours as you would any other well engineered project and begin with research. Your success will depend on timing, organization and diversity. Specific points about the birds that will help: type and population, flight patterns and times, entryways and exits, and nesting, feeding and roosting habits. Note the seasonality of the problem as well as the legal and public relations environment in which you will be working. Inspect your property to discover what the birds find attractive about it, and if the same conditions prevail at neighboring properties. Make educated guesses as to where the birds will go if you repel them. The Next Step to Manage Your Bird/Animal Pest Infestation Obviously, there are tradeoffs regarding the permanence, cost and time requirements of the solution. Because bird control is an inexact science, no one solution is perfect for every situation. Over the years, dozens of products have come onto the market. Ultrasonic Repellers. Sound from these units is inaudible to humans, but extremely irritating to birds. Frequency, amplitude and intensity are constantly varied to prevent birds from growing accustomed to the sound. Ultrasonic repellers work well in enclosed or semi-enclosed areas. Sonic Repellers. These units are generally used in large, open,
outdoor areas. They have adjustable features such as intermittent
sound, different volume levels and day/night operation to give the
user many options and to prevent birds from acclimating. Roost Inhibitors. These non-toxic, environmentally safe chemicals create a sticky, irritating, uncomfortable surface where birds will not want to roost. These mostly inert-ingredient chemicals are available in either
gel or liquid formulations to accommodate different applications.
These products “set” semi-clear, making them aesthetically
acceptable, and will last about one year. Physical Exclusions and Barriers. Physical exclusions keep birds out of an area by sealing or covering
all access points. Netting is a permanent solution. Physical barriers keep birds away by making the landing strip or
roosting surface permanently unusable. The barrier consists of long
metal strips with sharp prongs, “fingers,” coiled wire
or needles jutting from the base. Good Sanitation Before installing products, clean the area of all nests, droppings and garbage or unsealed food. This eliminates any incentive the birds may have to stay on your property. It is always best to start a bird control regimen before “bird
season” begins, because it is easier to keep the birds away
than to rout them once they have staked a claim. The birds may go
away overnight or it may take a few weeks. A combination of methods is always more effective than a single
product because you can assail more than one of the birds’ senses. Effectiveness will vary by situation and by product. The best choices
are products that involve change of some sort. Devices that vary their output or that use movement will keep the
birds “on their toes.” — as seen in Carlson Report, November 1993 HEALTH HAZARDS ASSOCIATED WITH BIRD AND BAT DROPPINGS Health risks from birds and bats are often exaggerated. Nevertheless, large populations of roosting birds may present the risk of disease to people nearby. The most serious health risks arise from disease organisms that can grow in the nutrient-rich accumulations of bird droppings, feathers and debris under a roost — particularly if roosts have been active for years. External parasites also may become a problem when infested birds or bats leave roosts or nests. The parasites then can invade buildings and bite people. Histoplasmosis Histoplasmosis is caused by a fungus (Histoplasma capsulatum) found primarily in the areas drained by the Mississippi and Ohio rivers. Both humans and animals can be affected. The disease is transmitted to humans by airborne fungus spores from soil contaminated by pigeon and starling droppings (as well as from the droppings of other birds and bats). The soil under a roost usually has to have been enriched by droppings for two years or more for the disease organism to reach significant levels. Although almost always associated with soil, the fungus has been found in droppings (particularly from bats) alone, such as in an attic. Infection occurs when spores, carried by the air are inhaled — especially after a roost has been disturbed. Most infections are mild and produce either no symptoms or a minor influenza- like illness. On occasion, the disease can cause high fever, blood abnormalities, pneumonia and even death. In some areas, including portions of Illinois, up to 80 percent of the population show evidence of previous infection. Outbreaks of histoplasmosis have occurred in Central Illinois. The National Institutes of Health (NIH) has reported a potentially
blinding eye condition — presumed ocular histoplasmosis syndrome
(OHS) — that probably results from the fungus. NIH estimates
that 4 percent of those exposed to the disease are at risk of developing
OHS. Cryptococcosis Pigeon droppings appear to be the most important source of the disease fungus Cryptococcus neoformans in the environment. The fungus is typically found in accumulations of droppings around roosting and nesting sites, for example, attics, cupolas, ledges and water towers. It has been found in as many as 84 percent of samples taken from old roosts. Even when old and dry, bird droppings can be a significant source of infection. Like histoplasmosis, most cryptococcosis infections are mild and may be without symptoms. Persons with weakened immune systems, however, are more susceptible to infection. The disease is acquired by inhaling the yeast-like cells of the organism. Two forms of cryptococcosis occur in humans. The generalized form begins with a lung infection and spreads to other areas of the body, particularly the central nervous system, and is usually fatal unless treated. The cutaneous (skin) form is characterized by acne-like skin eruptions or ulcers with nodules just under the skin. The cutaneous form is very rare, however, without generalized (systemic) disease. Outbreaks (multiple cases at a location) of cryptococcosis infections have not been documented. Other diseases Other diseases carried or transmitted by birds affect man to a lesser degree. Psittacosis is normally mild in man; however, serious illness can occur rarely. Pigeons and sparrows also have been implicated (along with many other species of birds) as reservoirs for encephalitis viruses such as Saint Louis encephalitis virus, which are carried by mosquitoes. Bats and disease Bats are associated with a few diseases that affect people, such as rabies and histoplasmosis. Rabies is a dangerous, fatal disease, but only about 5 percent of bats submitted for testing are infected with the rabies virus. In recent years, there has been increased concern about the risk of rabies transmission following contact with bats. If an injured or ill bat is found in or around a structure, it should be removed. Because most bats will try to bite when handled, they should be picked up with tongs or a shovel. (contact your local animal control officer or the Illinois Department of Natural Resources at 217- 785-8774 for information on safe bat capture.) If a bat has bitten or scratched a person or pet or is found in your home, capture the bat without touching it with your hands and without crushing its head. If the bat is dead, refrigerate it (DO NOT freeze) and then contact your local health department immediately for instructions. Bats with rabies have been identified in most areas of the state. In recent years, bats have been the most common animal identified with rabies in the state. The incidence of histoplasmosis being transmitted from bat droppings to humans is not thought to be high. Nevertheless, fresh bat droppings (unlike fresh bird dropping) can contain the histoplasmosis fungus. Bat droppings do not need to come into contact with soil to be a source of the disease. Ticks, mites and other parasites Bird or bat roosts can harbor parasites that may invade buildings. Although these parasites can bite and irritate, they are unlikely to transmit diseases to humans. The northern fowl mite and chicken mite are usually the main culprits. Other parasites that may cause problems inside buildings include the pigeon nest bug and the bat bug (both related to the beg bug), soft ticks, biting lice and the pigeon fly. Although most parasites associated with bird or bat roosts die quickly after the birds or bats leave, some may live for several weeks. Droppings, feathers, food and dead birds under a roosting area can breed flies, carpet beetles and other insects that may become major problems in the immediate area. These pests may fly through open windows or crawl through cracks to enter buildings. If birds or bats are discouraged from roosting around buildings, most of the parasites associated with them will soon die. If the pests are a problem after birds or bats have been excluded, the roost area may be treated with a residual insecticide appropriately labeled by the U.S. Environmental Protection Agency for control of fleas, ticks, mites and similar pests. Removal and cleanup of bird and bat droppings If there is a small accumulation of droppings from a few birds or bats, it can be cleaned up with soap and water. If large quantities of bird or bat droppings are present, contact an environmental engineering consultant for advice. Workers should follow certain precautions to minimize risk from disease organisms in the droppings:
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