Pigeons have long been a part of city life, but in recent years their numbers have grown out of control in many urban areas. This overpopulation of pigeons has caused a myriad of problems that have led cities and citizens to take action. In this article, we will explore the reasons why so many people are trying to stop or cull the pigeons in their towns.
The Rise of the Urban Pigeon
Pigeons are descended from wild rock doves that inhabited sea cliffs and mountains. However, these birds quickly adapted to live alongside humans in urban environments. The ample food sources provided by litter, refuse, and handouts enabled pigeons to thrive in cities across the globe.
Pigeons are well suited to urban life for the following reasons:
- They can eat a wide variety of food from crumbs to insects.
- Their robust immune systems allow them to develop resistance to pesticides.
- They can nest on ledges of buildings where they are protected from predators.
- Their ability to fly allows them to get around the city with ease.
Due to the lack of natural predators in cities and their incredible adaptability, pigeon populations began to explode in urban areas in the 19th and 20th centuries. Today, their numbers have reached record highs in many towns and cities.
Problems Caused by Large Pigeon Populations
While pigeons may seem harmless, large flocks can cause a surprising array of issues for a city and its residents. Some of the major problems associated with overpopulation of urban pigeons include:
Property Damage
Pigeon droppings are highly acidic and can corrode metal and limestone structures. The corrosive mess also ruins wood and paintwork. Historic buildings and precious monuments can be disfigured and decayed by accumulated pigeon excrement.
Noise Pollution
The loud cooing and fluttering of wings from masses of pigeons nesting and roosting can disrupt sleep and trouble workers. Pigeons vocalize frequently during mating and nesting seasons.
Health Risks
Pigeon droppings contain fungi that can cause respiratory illnesses in humans. Feathers and feces also provoke allergies in some people. When stirred up, dried droppings release particles that are easily inhaled.
Disease Transmission
Pigeons can harbor and spread diseases to humans such as:
- Histoplasmosis – lung infection from fungus in droppings
- Cryptococcosis – fungal disease from yeast in droppings
- Ornithosis – viral respiratory illness
Feeding pigeons also contributes to rat infestations, as the birds drop food that rats then scavenge.
Airplane Hazards
Dense flocks are hazardous to aircraft taking off and landing at airports. Collisions between planes and pigeons have caused fatal accidents.
Economic Loss
Cleaning acidic pigeon mess off buildings, structures, and signs entails huge costs over time. Droppings also deter tourism and shoppers from public spaces fouled with feces. In addition, pigeons cost the airline industry millions of dollars annually in damaged planes.
Methods to Control Pigeon Overpopulation
Due to the extensive problems spawned by burgeoning pigeon populations, cities have taken varied approaches to curb numbers and mitigate issues. Some of the key methods used to control pigeon numbers include:
Pigeon Population Control and Management
| Method | Description | Pros | Cons |
|---|---|---|---|
| Culling | Trapping and killing pigeons by CO2 or cervical dislocation |
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| Contraception | Feeding flock chemicals or drugs to reduce fertility |
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| Habitat Modification | Removing food sources, water, and nesting sites |
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Public Health Measures
Alongside trying to reduce pigeon flock sizes, some steps can be taken to minimize human health risks including:
- Regular park and sidewalk cleaning
- Disinfecting surfaces prone to droppings
- Issuing protective equipment to cleanup crews
- Educating the public on health hazards
- Enforcing fines for feeding pigeons in public areas
Structural Deterrents
Physical obstacles and barriers can be installed to try to prevent pigeons from landing and roosting in problematic areas. Common deterrents include:
- Pigeon netting over rooftops and ledges
- Metal “bird spikes” on signage, statues, and window sills
- Sonic and ultrasonic bird repellers
However, pigeons frequently find ways around deterrents making them minimally effective in the long-term.
Case Study: Trafalgar Square Pigeon Management
Trafalgar Square is one of London’s most famous public spaces and iconic landmarks. But by the 1990s, its stone balustrades, ledges, and statues were heavily stained by pigeon droppings. The acidic mess was also damaging the square’s monuments.
To address the spiraling pigeon problems, the Greater London Authority implemented new feeding bans with stricter enforcement. They also began culling thousands of pigeons annually. Volunteer falconers were brought in to fly hawks in the square which deterred pigeons through fear predation.
After 15 years of sustained effort, pigeon numbers decreased substantially from 4,500 birds in 2000 to around 350 in 2016. The coordinated policies renewed the square’s splendor and cleaned its surfaces of corrosive guano. This demonstrated that long-term application of multiple control measures could successfully reduce a giant, hazardous pigeon population plaguing an iconic location.
Conclusion
In summary, urban pigeon overpopulation causes an array of nuisance, health, sanitation, and economic issues for cities. Control measures aim to either cull existing flocks or reduce their food, water, and nesting resources. Deterrents also minimize roosting opportunities. A long-term, multi-pronged approach is required to humanely shrink pigeon populations to less problematic levels.
Pigeons will likely remain fixtures in city spaces globally. However, through sustained management efforts, cities can reach an improved equilibrium where pigeon numbers are kept in balance and their detrimental impacts are ameliorated. This enables urban dwellers and pigeons to more harmoniously coexist.
