Feather plucking is not the name of a disease. It is a bird pulling out, breaking or chewing off its own feathers, and the reasons behind it vary widely; a good number of them are medical. “It is bored” is the easiest explanation, and usually not the first place to look.

First, what is not plucking

Once or twice a year a bird moults: over a few weeks feathers drop and regrow in an even pattern. The bird is irritable, sleeps more and preens heavily because the sheaths of new feathers itch. In a moult the skin stays covered and the loss is symmetrical.

Plucking is asymmetrical and limited to where the beak reaches: chest, under the wings, legs, lower back. The head and the nape stay perfectly feathered, because the bird cannot reach them. Feather loss on the head means the cause is probably not plucking and needs looking at separately.

Medical causes are ruled out first

In a good share of the plucking cases we see, something physical is underneath. The common ones:

Skin and follicle disease. Anything that itches sends a bird to its own feathers.
Internal parasites. In budgerigars and cockatiels, giardia can present with itching and plucking.
Liver disease. Fatty liver is common in birds fed only on seed, and it ruins feather quality.
Nutritional deficiency. A diet of millet and sunflower seed leaves a bird short of vitamin A, which shows in the skin and the feathers.
Respiratory disease. A bird that is uncomfortable worries at itself.
Constant hormonal stimulation. Long daylight, a permanent mirror, being stroked down the back and box-like hiding places can keep a bird in breeding condition all year.

So the first step is an examination. We look at the skin, examine the droppings and take blood if it is warranted. Discussing behaviour before the cause is known usually wastes time.

Three things missed in the environment

Sleep. A bird needs ten to twelve hours in darkness and quiet. A cage in the living room with the television on does not provide that, and chronic sleep loss shows up as restlessness and plucking.

Bathing. A bird that cannot bathe regularly gets dry skin. A spray of lukewarm water a few times a week, or a shallow dish it can step into, is enough for most birds.

Something to do. A bird alone in a cage with nothing to chew and nobody around all day makes a project of its own body. Fresh branches, things that can be shredded, and feeding arrangements where the food is not simply there are the answer.

What not to do yourself

A collar is the first thing people think of and on its own it is wrong. It does not remove the cause, it interferes with feeding and balance, and in most birds it raises the stress. If one is needed, it is fitted after an examination and to the right size.

The chilli and chemical sprays described online irritate the skin and make the problem worse.

When to call

If the skin is broken, if there is bleeding, or if the bird chews at one spot
If feather loss comes with reduced appetite, changed droppings or a bird that has gone quiet
If feathers are also missing from the head and the nape
If there is any change in breathing

Plucking can be managed when it is looked at early. Once it has become a habit the behaviour can continue even after the cause is resolved, which is why waiting does not help.