Feral Pigeon

Columba Livia

Appearance Usually blue-gray with a white rump. They have iridescent feathers on the head and neck; two broad black bars across each wing and a broad dark band across the end of the tail. They can also display white, brown or gray plumage. Lifecycle Pigeons usually have 3 or 4 broods per year, with 2 eggs in each clutch with 6 broods per year being possible in ideal conditions. Eggs are a solid bright white colour that have an incubation period of around 18 days. Fledglings leave the nest in around 35 days. The lifespan of a pigeon is 3 to 4 years in the wild and up to 16 years in captivity.

Habits

Pigeons are not migratory, their natural instinct is to stay near their birth site. Nest building is very simple and often consists of a few stiff twigs built on small flat areas away from the ground. An individual feral pigeon produces around 12 kg of excrement each year.

Damage

Pigeons cause extensive damage to air-conditioning units and other roof top machinery. The air conditioning units will suck bacteria, fungal agents and ectoparasites into the building which is a serious health risk. Debris from roosting flocks builds up, causing gutters and drains to block, damage to roofs and other structures, and creating potential fire hazards.

Pigeons will build nests next to, or on top of other dead birds. This will increase the risk of disease, and the risk of other pests entering buildings. Damage to buildings and monuments occur due to the highly corrosive nature of the uric acid in pigeon droppings which can also represent a slip and fall hazard. Your business image can be damaged by the mess that pigeons make.

Disease

More than 40 diseases are associated with pigeons that infect both man and domestic pets including paramyxovirus infection and paratyphoid disease.

Pseudotuberculosis A common and deadly infectious disease caused by mycobacteria, mainly Mycobacterium tuberculosis. Tuberculosis most commonly attacks the lungs (as pulmonary TB) but can also affect the central nervous system, the lymphatic system, the circulatory system, the genitourinary system, bones, joints and even the skin.

Salmonellosis Most people infected with the Salmonella bacteria develop diarrhea, fever, vomiting, and abdominal cramps 6 to 72 hours after infection. In most cases, the illness lasts 3 to 7 days.

Coccidiosis is a parasitic disease of the intestinal tract of animals and humans, caused by coccidian protozoa. The disease spreads by contact with infected feces, or ingestion of infected tissue. Diarrhea, which may become bloody in severe cases, is the primary symptom. Coccidian organisms are usually species-specific. One well-known exception is toxoplasmosis.

aspergillosis is a rapidly invasive Aspergillus infection in the lungs that can cause repeated coughing up of blood, fever, chest pain, and difficulty breathing. Symptoms include fever, chills, shock, delirium, and blood clots. The person may develop kidney failure, liver failure (causing jaundice), and breathing difficulties. Death can occur quickly.

Encephalitis is an acute inflammation of the brain, commonly caused by a bacterial infection such as toxoplasmosis. Brain damage occurs as the inflamed brain pushes against the skull, and can lead to death. Adult patients with encephalitis may experience an acute onset of fever, headache, confusion, and sometimes seizures. Younger children or infants may show irritability, anorexia and fever.

Newcastle disease Newcastle Disease Virus (NDV) is highly contagious. Transmission occurs by exposure to faecal and other excretions from infected birds, and through contact with contaminated feed, water, equipment and clothing. Exposure of humans to infected birds can cause mild influenza-like symptoms and conjunctivitis, an abnormal eye discharge due to inflammation of the membrane lining the inside of the eyelid. The infection can also cause nasal discharge, sneezing, and pneumonia. Left untreated, the infection tends to become chronic, lasting weeks or months.

Borreliosis - Lyme Disease - Caused by the bacteria Borrelia recurrentis and several other borrelia strains spread from wild rodents by deer ticks or lice. Lyme disease can attack the skin, heart and nervous system and cause swelling to the brain and spinal cord resulting in paralysis and blindness. The early symptoms can be similar to severe flu and often it's wrongly diagnosed. Incubation is from 1-15 days. Symptoms include the sudden onset of fever lasting for 3-5 days, ends with a crisis. Then a febrile period of 2-4 days is followed by one to ten or more recurrences of fever accompanied by severe headaches, nausea, vomiting, diarrhoea, jaundice and sometimes a macular rash with bleeding due to thrombocytopenia. Many lesions occur, including enlarged, soft, infarcted spleen, hepatomegaly, hemorrhages in bone marrow and skin, myocarditis, bronchopneumonia, and meningitis. Cranial nerve involvement is possible. Also flu like symptoms, which resolve in about three weeks. 8-10% of people develop cardiac problems several weeks later.

Manifestations include atrioventricular block, cardiomyopathy, heart failure, myocarditis, and pancarditis. 15% develop neurologic disorders such as facial nerve palsies which usually resolve. Other manifestations include meningitis, cranial neuritis, radiculoneuritis, neuropathy, and encephalopathy. 60% develop arthritis which may remain latent with symptoms developing 4 years later. Most cases of Lyme disease can be treated successfully with a few weeks of antibiotics.

Toxoplasmosis - (Toxoplasma dondi) is an infection that invades human tissue and can severely damage the central nervous system, especially in babies. Pregnant women are in extreme danger if infected. Toxoplasmosis occurs in humans usually as low-grade fever or muscle pain for a few days. A normal immune system will suppress the infection but the tissue cysts can persist in the host for many years. In immunocompromised individuals, those dormant cysts can be reactivated and cause many lesions in the brain, heart, lungs, eyes, etc. Without a competent immune system, the animal or human will most likely die from the infection. The disease can spread by contact with infected feces.

Histoplasmosis is a fungus disease contracted through airborne spores. Symptoms may be anything from a mild influenza to blood abnormalities and fever, or even death. An eye condition from this disease can lead to blindness.

Cryptococosis an airborne fungus disease (cryptococcus neoformans) found in dust particles contaminated by pigeon droppings. The cryptococcus organisms can enter the bloodstream from the lungs and spread elsewhere in the body. Common symptoms are: Fever, Cough, Chest pain, coughing up blood, headaches, stiff neck, visual problems, nausea, vomiting, weight loss, fatigue and skin lesions.

Ornithosis causes fever, chills, fatigue, a rash and lung problems such as shortness of breath and a cough. It can also lead to rales, which are small clicking, bubbling or rattling sounds coming from the lung.

Ectoparasites that infest both pigeons and their nests include fleas, ticks and mites.

The most important ectoparasites of feral pigeons are the red blood mite, Dermanyssus gallinae, and the pigeon tick, Argas reflexus, both of which can migrate into human living space. The bites of the red blood mite are irritating but harmless, whereas the pigeon tick can cause severe health problems to predisposed persons.

Welts and skin infections may result from mite bites.

Bacteria, fungal agents and ectoparasites found in pigeon droppings represent a serious health risk.