Common Parasites in Birds

If recognized early, most parasitic infections in birds can be treated

Sick bird at vet

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Parasites can cause serious health problems in birds, just as they can affect other animals and people. More than just worms or mites, parasites can come in many forms.

It's important for bird owners to familiarize themselves with the most common parasites that infect pet birds and the symptoms that they cause. Knowing which signs of illness to look for can help you make sure that your pet receives prompt veterinary attention.

Types of Bird Parasites

Here's a list of some of the most common parasites that infect pet birds and how to recognize them. 


This parasitic fungus affects a bird's respiratory system. Caused by the fungus Aspergillus (and frequently shortened to "asper"), this infection is very common in pet parrots, as well as mallards and other ducks in the wild. Captive hawks and falcons are also susceptible to Aspergillosis, particularly when kept in unsanitary conditions.

This fungus is found primarily on decaying matter such as garbage or a compost pile, or in a dirty cage. A bird with Aspergillosis will show symptoms that resemble the human flu, including difficulty breathing, abnormal or unusual droppings (including diarrhea), nasal discharge, eye crustiness, and weight loss.

Treatment of Aspergillosis with antibiotics can be successful if it's caught early. For a bird with a chronic case of this infection, the prognosis is not good.

To prevent Aspergillosis, keep your bird's cage clean, wash all fruits and vegetables before feeding them to your bird, and wash your hands before and after handling your bird.


This parasite attacks the gastrointestinal tract of a pet bird, and, like Aspergillosis, can be transmitted when a bird eats contaminated food. The symptoms of Giardia in birds, as in people, include severe diarrhea, weight loss, and dehydration. Their droppings, weirdly, may resemble popcorn. Birds infected with Giardia may also display feather-plucking and other signs of itching and may become more vocal. 

Giardia is most common in birds of the parrot family, including budgies, cockatoos, cockatiels, macaws, and parrots.

This is a zoonotic illness, meaning an infected bird can pass the infection along to a human, so be careful when handling your pet. Frequent hand washing is one of the surest ways to prevent Giardia transmission. 


Although less common than other parasites, Sarcocystis is a bird owner's worst nightmare. These parasites can cause a fatal infection that has a few different varieties. One affects the bird's neurological system, one causes muscular disease, and a third affects the bird's lungs and pulmonary system.

Symptoms of Sarcocystis include lethargy, shortness of breath, yellow droppings, tail bobbing, and in extreme cases, a bird may suddenly die. Like Giardia, Sarcocystis also is zoonotic.

Scaly Face Mites 

Scaly Face Mites can wreak havoc on a bird's skin and plumage. This parasitic condition disproportionately affects budgies but can infect canaries and finches as well.

Like the name suggests, this infection displays as white, scaly growths on the bird's beak, mouth, nostrils, and eyes. There's also a version of the infection that can cause scaly growths on the bird's legs.

Birds will lose feathers, and their legs and beaks can appear deformed, sometimes even after treatment. Catching this illness early is crucial to reduce the risk of a bird being permanently scarred. It's treated by an avian veterinarian with anti-parasitic medications, either via injection or orally. 

Preventing Parasitic Infection in Birds

The key to keeping your bird free of parasitic infection is to make sure he has a nutritious diet, so if he does fall ill, his immune system can work to fight off the infection. Make sure his living area is kept clean and free of any mold or other growths. Washing your hands frequently when socializing with your bird is important as well. 

Article Sources
The Spruce Pets uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. Parasitic Diseases Of Pet BirdsVeterinary Manual, 2020

  4. Scaly Mites Symptoms and Treatments. Bird Vet Melbourne, 2020