What is beak and feather disease?

Wednesday, 1 March 2023

  • Estimated reading time 5 minutes

Everything you need to know about beak and feather disease

It’s a sorry sight: a sickly, scruffy Sulphur-crested Cockatoo with a long, misshapen beak and a bald spot.

Unfortunately, this bird is in the late stages of infection from a disease called psittacine beak and feather disease, or PBFD. Sadly, the prognosis is grim – it’s an incurable disease, but it’s also largely preventable.

Here’s everything you need to know about psittacine beak and feather disease, including the easy steps we can all take to help reduce the spread and keep our native birds safe.

Two Sulphur-crested Cockatoos are perched side-by-side on a colourbond fence in a suburban backyard. The bird on the left appears normal and healthy, but the bird on the right is clearly unwell with many missing feathers and an overgrown, deformed beak, all clear signs of psittacine beak and feather disease.
A Sulphur-crested Cockatoo (left) with missing feathers and a deformed beak: clear signs of psittacine beak and feather disease. Photo by Daria Nipot via Shutterstock

What is psittacine beak and feather disease?

Psittacine beak and feather disease (PBFD) is a common and highly-infectious viral disease found in wild and captive birds. While it mostly affects birds in the parrot family (including cockatoos and lorikeets), different strains of the virus have been reported in other species of birds.

Also known as psittacine circoviral disease (PCD) or ‘bald cocky disease’, the virus can be transmitted orally (by sharing food) or through faeces, skin or feathers. It can survive on natural and artificial surfaces, including nest hollows and feed stations, for many months.

PBFD attacks and kills the fast-growing cells of the feathers, beak and claws. It also suppresses the immune system, leaving birds vulnerable to secondary infection. Sadly, as there is no effective cure or treatment for PBFD, it is often fatal.


First described in 1888, PBFD appears to have originated in Australia. Today it is widespread, having been reported in every state and territory, and affects at least 38 species of native parrots.

While the virus isn’t a significant threat for the conservation of most native parrots – it is most prevalent in our more widespread species – PBFD is listed as a key threatening process, with potentially devastating impacts on threatened populations of Australian parrots. PBFD has a high mortality rate in nestlings, both in captivity and in the wild.

PBFD can also be transmitted by people: anyone who has been in contact with an infected bird can spread the disease via their clothing or hair. However, PBFD presents no known risk to human health.

What are the symptoms of psittacine beak and feather disease?

Depending on the age and species of the bird, the clinical signs and progression of PBFD are highly variable. It may take weeks or even years for a bird to show any physical symptoms, and some birds can appear normal in the early stages of the disease – making it difficult to detect in wild populations.

In young birds, signs and symptoms of acute PBFD include:

  • Weight loss
  • Diarrhoea
  • Depression
  • Anaemia
  • Sudden changes or abnormalities in developing feathers
  • Sudden death.

Signs of chronic infection in older birds include:

  • Abnormal loss, colour or development of feathers
  • Deformed or overgrown beak or claws
  • Immunosuppression
  • Feather loss and baldness
  • Difficulty eating or flying, and
  • Eventual death.

Look out for:

  • Dead, broken or deformed feathers (may appear curled or short and club-shaped)
  • Off-white or ‘dirty’ feathers in birds with white plumage, such as Sulphur-crested Cockatoos
  • Shorter/missing tail and wing feathers (especially in Rainbow Lorikeets)
  • Unusual colour changes, such as green feathers turning yellow, or blue feathers turning white
  • Cracking and peeling of the outer layers of the claws and beak (may appear flaky or shiny, due to loss of powder down)
  • A deformed, overgrown or brittle beak or claws.

Watch for runners!

In some parrot species, including Budgerigars and Rainbow Lorikeets, birds with PBFD often lose feathers from their wings and tail – and thus lose their ability to fly. Called ‘runners’, infected adults are often mistaken for young birds. While some birds can recover from the disease, they remain as carriers of the virus for the rest of their life.

A cropped close-up of a sick Sulphur-crested Cockatoo against an orange and brown dappled background. The bird has dirty, raggedy feathers and an overgrown beak, clear signs of PBFD
‘Dirty’ feathers and a long, deformed beak are symptoms of PBFD. Photo by Kristian Bell via Shutterstock

What to do if you find a wild bird with suspected PBFD

While PBFD-infected birds may still be able to fly, it’s important that they are taken to a vet or wildlife carer to ease their suffering and the risk of transmission to other, healthy birds. Without intervention, their prognosis is grim – missing feathers compromise their ability to regulate their body temperature and waterproof their plumage, their long and brittle beak and claws cause feeding difficulties, and their weakened immune system makes them vulnerable to infection.

If you find a wild bird with any of these symptoms and it is safe to do so, try to capture and transport it to your local vet or wildlife carer for assessment.

For smaller parrots, use a cardboard box, as this can be disposed of after use. For larger birds, use a plastic or metal box or carrier which can be disinfected after use. As this is a highly infectious disease, remember not to keep any birds with suspected PBFD in the same room or enclosure as other birds.

Shower and change your clothing after handling an infected bird.

If you are unable to capture the bird or if it is very sick, contact your local vet or wildlife rescue for advice.

A pair of Sulphur-crested Cockatoos preening eachother against a pale orange background.
A healthy pair of Sulphur-crested Cockatoos. Photo by Warren Wilson

How to help prevent the spread of PBFD

  • As PBFD occurs naturally and is widespread across Australia, it cannot be eradicated. There is no treatment or known cure, so preventing the spread of the disease is the only way we can control it.
  • Since PBFD is extremely infectious, it’s easily spread at feeding, roosting, nesting and watering sites – wherever birds flock together.
  • Bird feeders and feeding stations are easily contaminated, so the best way you can help prevent the spread of PBFD in your local bird population is to avoid feeding them.
  • However, if you must feed birds, reduce the risk of disease by replacing all food and cleaning and scrubbing the area daily, using a wildlife disinfectant or bleach solution by diluting bleach in water at 1:20 (1mL of bleach for every 20mL of water).
  • Don’t feed large flocks of birds at the same time and stop feeding birds immediately if you see any sick birds among them.

Conservation starts in your backyard

The best way to help the birds in your backyard long-term is to provide them with feeding and breeding habitat. To create more natural feeding resources for your feathered friends, check out our guide to creating a bird-friendly garden.

For any questions or advice on psittacine beak and feather disease, please contact your local vet or wildlife carer.

In the centre of the frame, a male Yellow-tailed Black-Cockatoo is perched on a bristly swamp banksia, grasping a cone between his claws against a dappled green background.
A healthy Yellow-tailed Black-Cockatoo feeding on a swamp banskia. Photo by Kate Geary