What is pigeon guano?
Pigeon guano is the droppings of feral pigeons, built up where the birds roost and nest. It collects on ledges, beams and parapets, in roof voids and lofts, under bridges and in car parks. A build-up is rarely just droppings: it usually includes feathers, nesting material and sometimes dead birds.
It builds up fast. A single pigeon can produce up to 12 kg of droppings a year (Stukenholtz et al., 2019), so a small flock using one roost can leave hundreds of kilos over a few years.
Is pigeon guano dangerous?
It can be, depending on how much there is and whether it is disturbed. HSE says everyday tasks such as cleaning windowsills “will not result in high exposures” (HSE). The risk rises with large, dried build-ups, because disturbing them puts contaminated dust into the air.
Breathing in that dust can cause psittacosis, a rare infection that brings flu-like illness and pneumonia. Droppings can also carry salmonella (HSE). Oxford City Council also lists cryptococcosis and histoplasmosis among the diseases pigeons can spread (Oxford City Council).
Who is most at risk?
- People with a weakened immune system. HSE says they should not directly carry out work involving bird droppings (HSE). UKHSA notes psittacosis can be more severe in elderly and immunocompromised people (UKHSA).
- Anyone clearing large build-ups without respiratory protection and dust control.
- People working nearby, if dust spreads from a poorly controlled clean-up.
Infection does not need long exposure. UKHSA says even brief contact with dried droppings can cause psittacosis in people with no other known risk (UKHSA).
What are the symptoms of psittacosis?
Symptoms usually start 1 to 4 weeks after exposure. They are often flu-like: fever, headache, muscle aches and a cough. Some people develop pneumonia. It is treated with antibiotics (UKHSA).
If you feel unwell after being around bird droppings, see your GP and tell them about the exposure.
Does pigeon guano damage buildings?
Yes. Acids released from bird droppings can cause lasting damage to stone, and limestone and calcareous sandstone are the most vulnerable. The acids make stone more porous, so frost can then crack the surface, and the damage can continue even after the droppings are cleaned off (Building Conservation Directory).
Guano causes other problems too:
- Blocked gutters and downpipes, leading to water damage and higher maintenance costs
- Slip hazards on walkways, steps and loading areas
- Smells, mites and insects around roosts
What should you do if you find pigeon guano?
For a small amount of fresh droppings: wear gloves and a suitable mask, dampen the droppings first, bag them, then wash your hands. Never dry sweep or use a pressure washer: HSE warns that high-pressure water creates contaminated droplets (HSE).
For dried build-ups, large amounts, or anything in a loft, roof void or at height: keep people away from the area and call a specialist. Our guide on how to choose a guano clearance contractor explains what to check, and how much pigeon guano removal costs explains what affects the price.
Then stop the birds coming back. Bird proofing such as netting, spikes or wire stops pigeons roosting in the same spot. Check for active nests first: they are protected by law while in use (Wildlife and Countryside Act 1981).
Locus Services clears pigeon guano safely across England, 24 hours a day, starting with a free site survey. See our pigeon guano removal service.