Health Hazards of Bird Droppings

The information below is courtesy of the United States Department of Agriculture:
Managing Vertebrate Invasive Species:
Proceedings of an International Symposium (G. W. Witmer, W. C. Pitt, K. A. Fagerstone, Eds).
USDA/APHIS/WS, National Wildlife Research Center, Fort Collins, CO. 2007.




Bird control can reduce health hazards and undesirable economic impacts for several industries.

Health Hazards of Bird Droppings

Starlings and other pest birds carry a plethora of diseases (Weber 1979, Gautsch et al. 2000, Clark and McLean 2003, Table 1). Avian salmonellosis (primarily, Salmonella enterica) has been documented in starlings (Feare 1984). This disease is transmissible to humans, poultry, and livestock. Chlamydiosis (also psittacosis, ornithosis, parrot fever) usually results from inhaling Chlamydophila psittaci that lives in dried feces. Starlings and blackbirds can infect humans and domestic fowl with C. psittaci (Grimes 1978, Grimes et al. 1979, Andersen et al. 1997). Starlings also carry Mycobacterium avium paratuberculosis, which causes Johne’s disease in cattle (also known as paratuberculosis) (Matthews and McDiarmid 1979, Corn et al. 2005). The bacteria are excreted in feces and milk. Johne’s disease costs the United States (US) dairy industry $200-250 million, annually (Beard et al. 2001, Ott et al. 1999). Starling fecal matter can pass transmissible gastroenteritis (TGE) to swine. Although the evidence is largely indirect and circumstantial, it is believed that during the winter of 1978-1979 starlings served as vectors for an outbreak of TGE in Nebraska that caused the loss of 10,000 swine in one month (Pilchard 1965, Bohl 1975, Gough et al. 1979, Johnson and Glahn 1994). Shiga toxin- producing Escherichia coli (STEC) is another disease the may be transmitted by starlings to cattle. In the cattle industry, annual costs of illnesses related to E. coli STEC exceeded $267 million (NCBA 2004). Humans get this disease when consuming tainted food products, especially ground beef. Knowledge of the movement patterns of starlings would be critical to understanding the real role that starlings have in epidemiologies of these diseases.

By disturbing soil or flooring at blackbird and starling roosts, humans can become ill with histoplasmosis, a fungal disease of the lungs caused by Histoplasma capsulatum (DiSalvo and Johnson 1979, Storch et al. 1980). Histoplasmosis recently was reported at a manufacturing facility in Nebraska used by starlings (J. Hobbs, personal communication). People at highest risk of exposure, however, are those working in agriculture, particularly poultry, or those coming in contact with bird or bat roosts that might have been abandoned a decade or more prior to disturbance (DiSalvo and Johnson 1979). Finally, West Nile virus (WNV) was confirmed in North America in 1999 and since that time has spread across the US. This is a serious, and life-threatening disease to humans and wildlife. Sullivan et al. (2006) found that red-winged blackbirds are WNV hosts and can disperse diseases along their migratory routes. The role of starlings in dispersing WNV is unknown, but starlings can act as hosts for the virus (Bernard et al. 2001), and thus may be involved in spreading the disease among vertebrates including, humans, horses, and birds.

Economic Impacts Diseases Carried by Birds

Pimentel et al. (2000) estimated that yearly starling damage to agriculture was US$800 million, based on a figure of US$5/ha. In 1999, three feedlot operators in Kansas estimated a loss of $600,000 from bird damage alone (US Department of Agriculture 2000). Data reported in 1968 from Colorado feedlots indicated the cost of cattle rations consumed during winter by starlings was $84 per 1,000 starlings. With the current cost of feed, the associated losses would certainly be much higher. In Idaho, some livestock facility operators estimated that starlings consumed 15 to 20 tons of cattle feed per day. The costs associated with starlings in the spread of livestock disease may be more important than food consumption. For example, the 10,000 pigs lost in Nebraska might be valued at nearly US$1.0 million in today’s market.

Table 1. Information on some diseases transmissible to humans and livestock that are associated with feral domestic pigeons, European starlings, and English sparrows.

Data originally from Weber (1979) and accessed in numerous Wildlife Services’ Environmental Assessments.

Disease Livestock Affected Symptoms
Erysipeloid Cattle, swine, horses, sheep, goats, chickens, turkeys, ducks Pigs – arthritis, skin lesions, necrosis, septicemia
Sheep – lameness
Serious hazard for the swine industry, rejection of swine meat at slaughter due to speticemia, also affects dogs
Salmonellosis All domestic animals Abortions in mature cattle, mortality in calves, decrease in milk production in dairy cattle
Colitis in pigs
Over 1,700 serotypes
Pasteurellosis Cattle, swine, horses, rabbits, chickens, turkeys Chickens and turkeys die suddenly without illness pneumonia, bovine mastitis, abortions in swine, septicemia, abscesses Also affects cats and dogs
Avian tuberculosis Chickens, turkeys, swine, cattle, horses, sheep Emaciation, decrease in egg production, and death in poultry. Mastitis in cattle Also affects cats and dogs
Streptococcosis Cattle, swine, sheep, horses, chickens, turkeys, geese, ducks, rabbits Emaciation and death in poultry. Mastitis in cattle, abscesses and inflamation of the heart, and death in swine Feral pigeons are susceptible and aid in transmission
Yersinosis Cattle, sheep, goats, horses, turkeys, chickens, ducks Abortion in sheep and cattle Also affects cats and dogs
Vibriosis Cattle and sheep In cattle, often a cause of infertility or early embryonic death. In sheep, the only known cause of infectious abortion in late pregnancy Of great economic importance
Listeriosis Chickens, ducks, geese, cattle, horses, swine, sheep, goats In cattle, sheep, and goats, difficulty swallowing, nasal discharge, paralysis of throat and facial muscles Also affects cats and dogs
Meningitis Cattle, sheep, swine, poultry Inflammation of the brain, newborn calves unable to suckle Associated with listeriosis, salmonellosis, cryptococcosis
Encephalitis (7 forms) Horses, turkeys, ducks Drowsiness, inflammation of the brain Mosquitos serve as vectors
Aspergillosis Cattle, chickens, turkeys, ducks Abortions in cattle Common in turkey poults
Candidiasis Cattle, swine, sheep, horses, chickens, turkeys Chronic mastitis in cattle, decreased milk flow and appetite loss Also affects dogs and cats
Histoplasmosis Horses, cattle, swine Chronic cough (in dogs), loss of appetite, weakness, depression, diarrhea, extreme weight loss Also affects dogs; actively grows and multiplies in soil and remains active long after birds have departed
Coccidiosis Poultry, cattle, and sheep Bloody diarrhea in chickens, dehydration, retardation of growth Almost always present in English sparrows; also found in pigeons and European starlings
American trypanosomiasis Infection of mucous membranes of eyes or nose, swelling Possible death in 2-4 weeks Caused by the conenose bug found on pigeons
Toxoplasmosis Cattle, swine, horses, sheep, chickens, turkeys In cattle, muscular tremors, coughing, sneezing, nasal discharge, frothing at the mouth, prostration and abortion Also affects dogs and cats
Chlamydiosis Cattle, horses, swine, sheep, goats, chickens, turkeys, ducks, geese In cattle, abortion, arthritis, conjunctivitis, enteritis Also affects dogs, cats, and many wild birds and mammals
Q fever Affects cattle, sheep, goats, and poultry May cause abortions in sheep and goats Can be transmitted by infected ticks

Electronic Bird Control

A form of bird control can reduce the risk of health hazards and lessen the economic impact of pest birds. Bird Gard has a built-in microprocessor continually randomizes the order the sounds play, the time and the relative pitch of each bird sound to give the impression many birds are in distress in the protected area.  This random technology prevents the birds from becoming habituated and keeps them out of the berry patch all the way through harvest.

Which Bird Gard Should I Buy?

Bird Gard has a variety of products to repel birds from one acre to thousands of acres. Choosing the right one depends on a number of factors. Compare Bird Gard’s bird control units or you can also contact a live human using the information below.
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